The G39DDC API SDK is implemented as a dynamic library (libg39ddcapi.so) for 32-bit i386 and 64-bit x86_64 platforms. It provides object-oriented and non-object-oriented interfaces to control the G39DDC device. This document describes the non-object-oriented interface. The libg39ddcapi.so library exports several functions that make it possible to control G39DDC receivers.
The API is not fully thread-safe so preferrably it should be used in single-threaded applications. It can be used in multi-threaded applications as well, but with some care: One G39DDC receiver can be controlled from a single user thread only.
A C/C++ header file g39ddcapi.h is a part of the SDK.
The lib39ddcapi.so library can be loaded to the application using the dlopen function of dynamic linking loader (link with -ldl).
After the library is loaded, it is required to get addresses of exported functions.
When the API is no longer required in the memory, the dlclose function can be used to unload the API. Before the dlclose is called, all the handles to G39DDC devices returned by the OpenDevice function must be closed by the CloseDevice function, otherwise the application can become to unpredictable state.
The following source code shows how to load the API.
#include <stdio.h> #include <dlfcn.h> #include "g39ddcapi.h" G39DDC_OPEN_DEVICE OpenDevice; G39DDC_CLOSE_DEVICE CloseDevice; void *API; int main(void) { //Loading the API API=dlopen("libg39ddcapi.so",RTLD_LAZY); if(API!=NULL) { //Retrieving addresses of used API functions OpenDevice=(G39DDC_OPEN_DEVICE)dlsym(API,"OpenDevice"); CloseDevice=(G39DDC_CLOSE_DEVICE)dlsym(API,"CloseDevice"); //Here place code that uses the API dlclose(API); } else { //If the dlopen fails printf("Failed to load libg39ddcapi.so. %s\n",dlerror()); } return 0; }
The G39DDC API provides the GetDeviceList function which returns list of available G39DDC device which can be open by the OpenDevice function.
The following source code produces list of serial numbers of available G39DDC devices.
#include <stdio.h> #include <stdint.h> #include <dlfcn.h> #include <stdlib.h> #include <errno.h> #include "g39ddcapi.h" G39DDC_GET_DEVICE_LIST GetDeviceList; void *API; int main(void) { uint32_t Count,i,ItemSize; G39DDC_DEVICE_INFO *DeviceList; //Loading the API API=dlopen("libg39ddcapi.so",RTLD_LAZY); if(API!=NULL) { //Retrieving address of the GetDeviceList function GetDeviceList=(G39DDC_GET_DEVICE_LIST)dlsym(API,"GetDeviceList"); //Retrieving number of available devices if(GetDeviceList(NULL,0,&Count,&ItemSize)) { if(Count!=0) { //Allocating memory for device information structures DeviceList=(G39DDC_DEVICE_INFO*)malloc(Count*sizeof(G39DDC_DEVICE_INFO)); if(DeviceList!=NULL) { //Retrieving information about available devices if(GetDeviceList(DeviceList,Count*sizeof(G39DDC_DEVICE_INFO),&Count,&ItemSize)) { printf("Available G39DDC devices count=%d:\n",Count); for(i=0;i<Count;i++) { printf("%d. SN: %s\n",i,DeviceList[i].SerialNumber); } } else { printf("GetDeviceList failed with error %d.\n",errno); } free(DeviceList); } else { printf("Out of memory\n"); } } else { printf("No available G39DDC device found.\n"); } } else { printf("GetDeviceList failed with error %d.\n",errno); } dlclose(API); } else { printf("Failed to load libg39ddcapi.so. %s\n",dlerror()); } printf("Press enter to exit\n"); getchar(); return 0; }
G39DDC device has to be open before it can be controlled. The API provide the OpenDevice function to open the device.
The following source code shows how to open the first available G39DDC device.
#include <stdio.h> #include <dlfcn.h> #include <errno.h> #include "g39ddcapi.h" G39DDC_OPEN_DEVICE OpenDevice; G39DDC_CLOSE_DEVICE CloseDevice; void *API; int main(void) { int32_t hDevice; //Loading the API API=dlopen("libg39ddcapi.so",RTLD_LAZY); if(API!=NULL) { //Retrieving addresses of the OpenDevice and CloseDevice API functions OpenDevice=(G39DDC_OPEN_DEVICE)dlsym(API,"OpenDevice"); CloseDevice=(G39DDC_CLOSE_DEVICE)dlsym(API,"CloseDevice"); //Opening the first available G39DDC device using predefined G39DDC_OPEN_FIRST constant hDevice=OpenDevice(G39DDC_OPEN_FIRST); if(hDevice>=0) { //Here place code that works with the open G39DDC device //Closing handle to opened G39DDC device CloseDevice(hDevice); } else { printf("OpenDevice failed with error %d.\n",errno); } dlclose(API); } else { //If the dlopen fails printf("Failed to load libg39ddcapi.so. %s\n",dlerror()); } return 0; }
The GetDeviceList function returns information about available G39DDC devices that can be open.
C/C++ declaration
int GetDeviceList(G39DDC_DEVICE_INFO *DeviceList,uint32_t BufferSize,uint32_t *Count,uint32_t *ItemSize);
Address retrieval
G39DDC_GET_DEVICE_LIST GetDeviceList=(G39DDC_GET_DEVICE_LIST)dlsym(API,"GetDeviceList");
Parameters
DeviceList[out] Pointer to array of G39DDC_DEVICE_INFO structures to be filled with information about available G39DDC devices.
This parameter can be NULL only if the BufferSize parameter is zero, otherwise the function fails.BufferSize[in] Specifies the size in bytes of the buffer pointed to by the DeviceList parameter. If this value is zero, function returns number of available G39DDC devices and makes no use of the DeviceList buffer.Count[out] Pointer to a variable that receives number of available G39DDC devices. This parameter cannot be NULL.ItemSize[out] Pointer to a variable that receives size of a single item of the buffer pointer to by the DeviceList parameter. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Opens G39DDC device by its serial number.
C/C++ declaration
int32_t OpenDevice(const char *SerialNumber);
Address retrieval
G39DDC_OPEN_DEVICE OpenDevice=(G39DDC_OPEN_DEVICE)dlsym(API,"OpenDevice");
Parameters
SerialNumber[in] Pointer to a null-terminated string that specifies the serial number of the G39DDC device to open. It can be used one of the following values instead of serial number:
Value Meaning G39DDC_OPEN_FIRST The function opens first available G39DDC device. G39DDC_OPEN_DEMO The function opens demo G39DDC device. This allows to work with the API without physical G39DDC device.
Return value
If the function succeeds, the return value is handle to the specified G39DDC device. This handle can only be used with functions of G39DDC API.
If the function fails, the return value is negative, and errno is set appropriately.
Remarks
The OpenDevice function can be called from any user thread, the returned handle can only be used in the same thread, otherwise application can become to unpredictable state.
Use the CloseDevice function to close G39DDC device handle returned by OpenDevice.
Closes G39DDC device.
C/C++ declaration
int CloseDevice(int32_t hDevice);
Address retrieval
G39DDC_CLOSE_DEVICE CloseDevice=(G39DDC_CLOSE_DEVICE)dlsym(API,"CloseDevice");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Checks if the device is still connected to the computer.
C/C++ declaration
int IsDeviceConnected(int32_t hDevice);
Address retrieval
G39DDC_IS_DEVICE_CONNECTED IsDeviceConnected=(G39DDC_IS_DEVICE_CONNECTED)dlsym(API,"IsDeviceConnected");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.
Return value
The function returns non-zero value if the device is still connected.
Zero is returned, if the device is disconnected (errno == 0) or the function fails (errno != 0).
Remarks
If it is determined that the device is disconnected, corresponding device handle is no longer usable and it should be closed using the CloseDevice function.
Retrieves information about the G39DDC device.
C/C++ declaration
int GetDeviceInfo(int32_t hDevice,G39DDC_DEVICE_INFO *Info,uint32_t BufferLength);
Address retrieval
G39DDC_GET_DEVICE_INFO GetDeviceInfo=(G39DDC_GET_DEVICE_INFO)dlsym(API,"GetDeviceInfo");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Info[out] Pointer to a G39DDC_DEVICE_INFO structure to be filled with information about the device. This parameter cannot be NULL.BufferLength[in] Size in bytes of the G39DDC_DEVICE_INFO structure.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets the front panel LED flashing mode.
C/C++ declaration
int SetLED(int32_t hDevice,uint32_t LEDMode);
Address retrieval
G39DDC_SET_LED SetLED=(G39DDC_SET_LED)dlsym(API,"SetLED");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.LEDMode[in] Specifies front panel LED flashing mode. It can be one of the following:
Value Meaning G39DDC_FRONT_PANEL_LED_MODE_DIAG Diagnostic flashing. G39DDC_FRONT_PANEL_LED_MODE_ON Always on. G39DDC_FRONT_PANEL_LED_MODE_OFF Always off.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetLED function to determine current flashing mode of the front panel LED.
A complete list of the diagnostic flashing patterns and their meaning is as follows:
No. Pattern Description Mode 1
Off No power 2
Long flash, equal gap No connection to computer 3
Two short flashes USB connected, radio off 4
One short flash followed by a long one USB connected, radio on, ready 5
Two short flashes followed by a long one USB connected, driver not installed 6
Three short flashes USB connected, driver installed, application not running
Determines current flashing mode of device's front panel LED.
C/C++ declaration
int GetLED(int32_t hDevice,uint32_t *LEDMode);
Address retrieval
G39DDC_GET_LED GetLED=(G39DDC_GET_LED)dlsym(API,"GetLED");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.LEDMode[out] Pointer to a variable that receives current flashing mode of device's front panel LED. For list of possible values, see SetLED. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Turns the G39DDC device on or off.
C/C++ declaration
int SetPower(int32_t hDevice,int Power);
Address retrieval
G39DDC_SET_POWER SetPower=(G39DDC_SET_POWER)dlsym(API,"SetPower");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Power[in] Specifies whether to turn on or off the device. If this parameter is non-zero the device is turned on, if it is zero the device is turned off.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If SetPower turns the device off, all the running streaming are stopped.
Use the GetPower function to determine current power state of the device.
The GetPower function determines whether the device is turned on or off.
C/C++ declaration
int GetPower(int32_t hDevice,int *Power);
Address retrieval
G39DDC_GET_POWER GetPower=(G39DDC_GET_POWER)dlsym(API,"GetPower");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Power[out] Pointer to a variable that receives current power state of the device. If it is non-zero, the device is turned on. If it is zero the device is turned off. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets absolute frequency of the demodulator for given channel.
C/C++ declaration
int SetFrequency(int32_t hDevice,uint32_t Channel,uint64_t Frequency);
Address retrieval
G39DDC_SET_FREQUENCY SetFrequency=(G39DDC_SET_FREQUENCY)dlsym(API,"SetFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Frequency[in] Specifies new absolute frequency of the demodulator in Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero., and errno is set appropriately.
Remarks
The function sets front-end frequency, relative DDC1, DDC2 and demodulator frequencies so that new absolute frequency of the demodulator is the required one.
Absolute frequency of the demodulator is given by the following formula:
faDEM[i] = fFE + frDDC1[i] + frDDC2[i] + frDEM[i]
Where faDEM[i] is absolute center frequency of the demodulator of i-th channel in Hz, fFE is front-end frequency (see SetFrontEndFrequency), frDDC1[i] is relative center frequency of the DDC1 in Hz (set using the SetDDC1Frequency function), frDDC2[i] is relative center frequency of DDC2 of i-th channel in Hz (set using the SetDDC2Frequency) and frDEM[i] is relative center frequency of the demodulator of i-th channel in Hz (set using the SetDemodulatorFrequency function).
Absolute center frequency of the demodulator is the real-world frequency that you are listening to.
Use the GetFrequency function to retrieve current absolute frequency of the demodulator.
Determines absolute frequency of the demodulator for given channel.
C/C++ declaration
int GetFrequency(int32_t hDevice,uint32_t Channel,uint64_t *Frequency);
Address retrieval
G39DDC_GET_FREQUENCY GetFrequency=(G39DDC_GET_FREQUENCY)dlsym(API,"GetFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Frequency[out] Pointer to a variable that receives current absolute frequency of the demodulator. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Returned value of the variable pointed to by the Frequency parameter is sum of front-end frequency and relative DDC1, DDC2 and demodulator frequencies. For more information, see remarks of the SetFrequency function.
Enables or disables the use of external reference as the clock source.
C/C++ declaration
int SetExternalReference(int32_t hDevice,int Enabled);
Address retrieval
G39DDC_SET_EXTERNAL_REFERENCE SetExternalReference=(G39DDC_SET_EXTERNAL_REFERENCE)dlsym(API,"SetExternalReference");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Enabled[in] Specifies the desired clock source: nonzero - external reference, zero - internal.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
External reference is optional. If the receiver does not support external reference, SetExternalReference fails. The following example shows how to determine the receiver supports external reference:
G39DDC_DEVICE_INFO DeviceInfo; int32_t hDevice; //handle to open G39DDC device GetDeviceInfo(hDevice,&DeviceInfo,sizeof(DeviceInfo)); if(DeviceInfo.HardwareOptions & G39DDC_HARDWARE_OPTIONS_EXTERNAL_REFERENCE) { //the receiver supports external reference } else { //the receiver does not support external reference }
Retrieves the current clock source.
C/C++ declaration
int GetExternalReference(int32_t hDevice,int *Enabled);
Address retrieval
G39DDC_GET_EXTERNAL_REFERENCE GetExternalReference=(G39DDC_GET_EXTERNAL_REFERENCE)dlsym(API,"GetExternalReference");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Enabled[out] Pointer to a variable that receives information about the current clock source. If it is non-zero, external reference is used, if it is zero, internal reference is used. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets input attenuator. The attenuator is applied for front-end frequencies (see SetFrontEndFrequency) below 60 MHz.
C/C++ declaration
int SetAttenuator(int32_t hDevice,uint32_t Attenuator);
Address retrieval
G39DDC_SET_ATTENUATOR SetAttenuator=(G39DDC_SET_ATTENUATOR)dlsym(API,"SetAttenuator");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Attenuator[in] Value that specifies desired attenuation level. The value must be one of the following:
Value Meaning G39DDC_ATTENUATOR_0dB No attenuation. G39DDC_ATTENUATOR_6dB 6 dB attenuation. G39DDC_ATTENUATOR_12dB 12 dB attenuation. G39DDC_ATTENUATOR_18dB 18 dB attenuation.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetAttenuator function to determine current setting of the attenuator.
Retrieves current setting of the attenuator.
C/C++ declaration
int GetAttenuator(int32_t hDevice,uint32_t *Attenuator);
Address retrieval
G39DDC_GET_ATTENUATOR GetAttenuator=(G39DDC_GET_ATTENUATOR)dlsym(API,"GetAttenuator");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Attenuator[out] Pointer to a variable that receives current attenuation. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Enables or disables input preamplifier. The preamplifier is applied to front-end frequencies (see SetFrontEndFrequency) above 50 MHz.
C/C++ declaration
int SetPreamplifier(int32_t hDevice,int Preamp);
Address retrieval
G39DDC_SET_PREAMPLIFIER SetPreamplifier=(G39DDC_SET_PREAMPLIFIER)dlsym(API,"SetPreamplifier");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Preamp[in] Specifies whether to enable or disable preamplifier. If this parameter is non-zero, the preamplifier is enabled. If the parameter is zero, the preamplifier is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetPreamplifier function to determine current state of the preamplifier.
Retrieves current state of input preamplifier.
C/C++ declaration
int GetPreamplifier(int32_t hDevice,int *Preamp);
Address retrieval
G39DDC_GET_PREAMPLIFIER GetPreamplifier=(G39DDC_GET_PREAMPLIFIER)dlsym(API,"GetPreamplifier");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Preamp[out] Pointer to a variable that receives current state of the preamplifier. The value is non-zero if the preamplifier is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets the frequency of the device's analog front-end.
C/C++ declaration
int SetFrontEndFrequency(int32_t hDevice,uint64_t Frequency);
Address retrieval
G39DDC_SET_FRONT_END_FREQUENCY SetFrontEndFrequency=(G39DDC_SET_FRONT_END_FREQUENCY)dlsym(API,"SetFrontEndFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Frequency[in] Specifies new front-end frequency in Hz. The value can be between (including) values provided by the FrontEndMinFrequency and FrontEndMaxFrequency members of the G39DDC_DEVICE_INFO structure. If the specified frequency is not equal to the FrontEndMinFrequency, it has to be multiple of the FrontEndFrequencyStep member of the G39DDC_DEVICE_INFO structure.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Changing of front-end frequency causes change of absolute frequency of the DDC1, DDC2 and demodulator in each channel.
Use the GetFrontEndFrequency function to retrieve current front-end frequency.
Retrieves current front-end frequency.
C/C++ declaration
int GetFrontEndFrequency(int32_t hDevice,uint64_t *Frequency);
Address retrieval
G39DDC_GET_FRONT_END_FREQUENCY GetFrontEndFrequency=(G39DDC_GET_FRONT_END_FREQUENCY)dlsym(hAPI,"GetFrontEndFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Frequency[out] Pointer to a variable that receives current current front-end frequency in Hz. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Enables or disables ADC dithering.
C/C++ declaration
int SetDithering(int32_t hDevice,int Enabled);
Address retrieval
G39DDC_SET_DITHERING SetDithering=(G39DDC_SET_DITHERING)dlsym(API,"SetDithering");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Enabled[in] Specifies whether to enable or disable ADC dithering. If this parameter is non-zero, dithering is enabled. If the parameter is zero, dithering is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetDithering function to determine current state of ADC dithering.
Retrieves current state of ADC dithering.
C/C++ declaration
int GetDithering(int32_t hDevice,int *Enabled);
Address retrieval
G39DDC_GET_DITHERING GetDithering=(G39DDC_GET_DITHERING)dlsym(API,"GetDithering");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Enabled[out] Pointer to a variable that receives current state of dithering. The value is non-zero if dithering is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Enables or disables noise blanker on ADC stream.
C/C++ declaration
int SetADCNoiseBlanker(int32_t hDevice,int Enabled);
Address retrieval
G39DDC_SET_ADC_NOISE_BLANKER SetADCNoiseBlanker=(G39DDC_SET_ADC_NOISE_BLANKER)dlsym(API,"SetADCNoiseBlanker");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Enabled[in] Specifies whether to enable or disable noise blanker. If this parameter is non-zero, noise blanker is enabled. If the parameter is zero, noise blanker is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetADCNoiseBlanker function to determine current state of the noise blanker.
Retrieves current ADC noise blanker state.
C/C++ declaration
int GetADCNoiseBlanker(int32_t hDevice,int *Enabled);
Address retrieval
G39DDC_GET_ADC_NOISE_BLANKER GetADCNoiseBlanker=(G39DDC_GET_ADC_NOISE_BLANKER)dlsym(API,"GetADCNoiseBlanker");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Enabled[out] Pointer to a variable that receives current state of noise blanker. The value is non-zero if noise blanker is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies ADC noise blanker threshold.
C/C++ declaration
int SetADCNoiseBlankerThreshold(int32_t hDevice,uint16_t Threshold);
Address retrieval
G39DDC_SET_ADC_NOISE_BLANKER_THRESHOLD SetADCNoiseBlankerThreshold= (G39DDC_SET_ADC_NOISE_BLANKER_THRESHOLD)dlsym(API,"SetADCNoiseBlankerThreshold");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Threshold[in] Specifies the maximum acceptable input signal. Maximum possible value of threshold is 32767.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetADCNoiseBlankerThreshold function to retrieve current threshold of the noise blanker.
Determines ADC noise blanker threshold.
C/C++ declaration
int GetADCNoiseBlankerThreshold(int32_t hDevice,uint16_t *Threshold);
Address retrieval
G39DDC_GET_ADC_NOISE_BLANKER_THRESHOLD GetADCNoiseBlankerThreshold= (G39DDC_GET_ADC_NOISE_BLANKER_THRESHOLD)dlsym(API,"GetADCNoiseBlankerThreshold");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Threshold[out] Pointer to a variable that receives threshold of ADC noise blanker. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Enables or disables frequency spectrum inversion.
C/C++ declaration
int SetInverted(int32_t hDevice,int Inverted);
Address retrieval
G39DDC_SET_INVERTED SetInverted=(G39DDC_SET_INVERTED)dlsym(API,"SetInverted");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Inverted[in] Specifies whether to enable or disable frequency spectrum inversion. If this parameter is non-zero, IF spectrum is inverted.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Retrieves current frequency spectrum inversion setting.
C/C++ declaration
int GetInverted(int32_t hDevice,int *Inverted);
Address retrieval
G39DDC_GET_INVERTED GetInverted=(G39DDC_GET_INVERTED)dlsym(API,"GetInverted");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Inverted[out] Pointer to a variable that receives non-zero value if the frequency spectrum inversion is enabled, and zero if the inversion is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Starts sending of IF snapshots.
C/C++ declaration
int StartIF(int32_t hDevice,uint16_t Period);
Address retrieval
G39DDC_START_IF StartIF=(G39DDC_START_IF)dlsym(API,"StartIF");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Period[in] Specifies time interval in milliseconds how often the IF snapshots are sent to IFCallback callback function.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using the SetPower function before use of StartIF, otherwise the StartIF function fails.
Too low value of the Period parameter can dramatically increase data flow through USB/PCIe which could cause breaking of running streaming.
Stops sending of IF snapshots.
C/C++ declaration
int StopIF(int32_t hDevice);
Address retrieval
G39DDC_STOP_IF StopIF=(G39DDC_STOP_IF)dlsym(API,"StopIF");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The IFCallback callback function is not called after StopIF returns.
Retrieves information about DDC format.
C/C++ declaration
int GetDDCInfo(uint32_t DDCTypeIndex,G39DDC_DDC_INFO *Info);
Address retrieval
G39DDC_GET_DDC_INFO GetDDCInfo=(G39DDC_GET_DDC_INFO)dlsym(API,"GetDDCInfo");
Parameters
DDCTypeIndex[in] Specifies index of DDC type. For more information, see remarks.Info[out] Pointer to a G39DDC_DDC_INFO structure to be filled with information about information of the DDC type.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetDDC1Count function to determine the number of possible DDC types of DDC1. In this case the DDCTypeIndex parameter can vary from zero to one less than the number determined by GetDDC1Count.
Use the GetDDC1Count function to determine the number of possible DDC types of DDC2. In this case the DDCTypeIndex parameter can vary from zero to one less than the number determined by GetDDC2Count.
Use the GetDDC1 function to determine current DDC type index of DDC1 and the GetDDC2 function to determine current DDC type of DDC2.
Retrieves number of DDC types supported by DDC1 for given channel.
C/C++ declaration
int GetDDC1Count(int32_t hDevice,uint32_t Channel,uint32_t *Count);
Address retrieval
G39DDC_GET_DDC1_COUNT GetDDC1Count=(G39DDC_GET_DDC1_COUNT)dlsym(API,"GetDDC1Count");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.Count[out] Pointer to a variable that receives number of DDC types. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets current DDC type of DDC1 for given channel.
C/C++ declaration
int SetDDC1(int32_t hDevice,uint32_t Channel,uint32_t DDCTypeIndex);
Address retrieval
G39DDC_SET_DDC1 SetDDC1=(G39DDC_SET_DDC1)dlsym(API,"SetDDC1");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.DDCTypeIndex[in] Specifies index of DDC type to be used in DDC1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetDDC1Count function to determine the number of possible DDC types of DDC1 for given channel. The DDCTypeIndex parameter can vary from zero to one less than the number determined by GetDDC1Count.
Number of DDC types of DDC1 for second channel (channel index 1) can be reduced. To determine number of available DDC types of DDC1 for second channel use the GetDDC1Count function with parameter Channel set to 1.
DDC1 streaming must not run when calling SetDDC1. In other words, DDC1 streaming that is started using the StartDDC1 function has to be stopped using the StopDDC1 function before calling of SetDDC1, otherwise SetDDC1 fails. The SetDDC1 function does not start and stop DDC1 streaming, just changes DDC type of DDC1.
Calling of SetDDC1 can change number of DDC types of DDC2, therefore it is useful to call the GetDDC2Count function immediately after SetDDC1.
Calling of SetDDC1 can change current DDC type of DDC2 and current bandwidth of demodulator filter if current DDC type index of DDC2 is greater than the DDCTypeIndex parameter, so it is useful to call the GetDDC2 and GetDemodulatorFilterBandwidth functions immediately after SetDDC1 to determine current DDC type of DDC2 and current bandwidth of demodulator filter.
Use the GetDDC1 function to determine current DDC type of the DDC1.
Retrieves information about current DDC type of the DDC1 for given channel.
C/C++ declaration
int GetDDC1(int32_t hDevice,uint32_t Channel,uint32_t *DDCTypeIndex);
Address retrieval
G39DDC_GET_DDC1 GetDDC1=(G39DDC_GET_DDC1)dlsym(API,"GetDDC1");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.DDCTypeIndex[out] Pointer to a variable that receives index of current DDC type of the DDC1. Received value can be passed to the GetDDCInfo function to to retrieve information about current DDC type of the DDC1. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets relative center frequency of DDC1 for given channel.
C/C++ declaration
int SetDDC1Frequency(int32_t hDevice,uint32_t Channel,int32_t Frequency);
Address retrieval
G39DDC_SET_DDC1_FREQUENCY SetDDC1Frequency=(G39DDC_SET_DDC1_FREQUENCY)dlsym(API,"SetDDC1Frequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.Frequency[in] Specifies new center frequency of DDC1 in Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The frequency is relative to front-end frequency (see SetFrontEndFrequency), it can be negative. Usable bandwidth at front-end output is specified by the FrontEndWindowWidth member of the G39DDC_DEVICE_INFO structure. The Frequency parameter should vary from (-(int32_t)FrontEndWindowWidth/2 + half of current usable bandwidth of DDC1) to (FrontEndWindowWidth/2 - half of current usable bandwidth of DDC1). Use GetDDC1 and GetDDCInfo functions to determine current usable bandwidth of the DDC1.
Changing of DDC1 frequency causes change of absolute frequency of the DDC2 and demodulator for given channel.
Absolute frequency of the DDC1 is given by the following formula:
faDDC1[i] = fFE + frDDC1[i]
Where faDDC1[i] is absolute center frequency of DDC1 of i-th channel in Hz, fFE is front-end frequency in Hz (set using the SetFrontEndFrequency function) and frDDC1[i] is relative center frequency of DDC1 of i-th channel in Hz (set using SetDDC1Frequency).
Changing of DDC1 relative frequency changes absolute frequency of the DDC1 and demodulator in the specified channel.
Use the GetDDC1Frequency function to determine current relative center frequency of the DDC1 for given channel.
The following example shows how to set absolute DDC1 center frequency of channel 0 to 11.01 MHz:
int32_t hDevice; //Handle to G39DDC device returned by the OpenDevice function SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1010000);
Retrieves current center frequency of DDC1 for given channel.
C/C++ declaration
int GetDDC1Frequency(int32_t hDevice,uint32_t Channel,int32_t *Frequency);
Address retrieval
G39DDC_GET_DDC1_FREQUENCY GetDDC1Frequency=(G39DDC_GET_DDC1_FREQUENCY)dlsym(API,"GetDDC1Frequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.Frequency[out] Pointer to a variable that receives current center frequency of DDC1 in Hz. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Starts DDC1 streaming for given channel.
C/C++ declaration
int StartDDC1(int32_t hDevice,uint32_t Channel,uint32_t SamplesPerBuffer);
Address retrieval
G39DDC_START_DDC1 StartDDC1=(G39DDC_START_DDC1)dlsym(API,"StartDDC1");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.SamplesPerBuffer[in] Specifies number of I/Q sample sets in each buffer passed to the the DDC1StreamCallback callback function. The value has to be multiple of 64 greater than zero. If it is zero, the StartDDC1 function fails. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using the SetPower function before StartDDC1 is used. Otherwise StartDDC1 fails.
Sweeping (see StartSweeping or StartSweepingEx) must not be running before StartDDC1 is used, otherwise StartDDC1 fails.
If the DDC1 streaming is already running before use of StartDDC1, StartDDC1 restarts the streaming except it was previously started with the same SamplesPerBuffer parameter. In this case StartDDC1 does nothing. Restart of DDC1 streaming stops of DDC2 and audio streaming of given channel. StartDDC1 does not restart DDC2 and audio streaming.
If DDC1 playback is running (started using StartDDC1Playback function) before use of StartDDC1, StartDDC1 stops it and starts DDC1 streaming from the device.
Use the StopDDC1 function to stop DDC1 streaming.
Decreasing value of the SamplesPerBuffer parameter decreases latency and it may increase CPU usage. Increasing value of the SamplesPerBuffer parameter increased latency and it may decrease CPU usage.
Stops DDC1 streaming for given channel.
C/C++ declaration
int StopDDC1(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_STOP_DDC1 StopDDC1=(G39DDC_STOP_DDC1)dlsym(API,"StopDDC1");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If DDC1 playback is running (started using StartDDC1Playback) before use of StopDDC1, the StopDDC1 function stops it.
The StopDDC1 function stops all the streaming beyond the DDC1 in processing chain (DDC2 and audio streaming) in specified channel. The streaming in the other channel is not affected
The DDC1StreamCallback and DDC1PlaybackStreamCallback callback functions are not called after StopDDC1 returns.
Starts DDC1 playback for given channel. It allows to pass previously recorded DDC1 I/Q samples to the processing chain instead of the samples received from the device.
C/C++ declaration
int StartDDC1Playback(int32_t hDevice,uint32_t Channel,uint32_t SamplesPerBuffer,uint32_t BitsPerSample);
Address retrieval
G39DDC_START_DDC1_PLAYBACK StartDDC1Playback=(G39DDC_START_DDC1_PLAYBACK)dlsym(API,"StartDDC1Playback");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.SamplesPerBuffer[in] Specifies number of I/Q sample sets in each buffer passed to the DDC1PlaybackStreamCallback callback to fill the buffer by the application and to the DDC1StreamCallback callback function. The value has to be multiple of 64 greater than zero. If it is zero, the StartDDC1Playback function fails. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.BitsPerSample[in] Specifies number of bits per I and Q samples. It is used for both DDC1PlaybackStreamCallback and DDC1StreamCallback callback functions. The possible value is one of the following:
Value Meaning 0 I and Q samples have default number of bits. It is given by by BitsPerSample member of the G39DDC_DDC_INFO structure which can be retrieved using the GetDDC1 and GetDDCInfo function. Possible values are 16 or 32 bits per sample, signed, little endian. 16 I and Q samples have 16 bit (16 bits per I, 16 bits per Q), signed, little endian. 32 I and Q samples have 32 bit (32 bits per I, 32 bits per Q), signed, little endian.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using SetPower function before use of StartDDC1Playback.
The StartDDC1Playback function stops DDC1 streaming that was previously started by the StartDDC1 or StartDDC1Playback function and starts DDC1 playback with new parameters. Stopping of DDC1 streaming stops DDC2 and audio steaming in each channel. StartDDC1Playback does not restart DDC2 and audio streaming.
Use the StopDDC1 function to stop DDC1 playback.
Pauses DDC1 playback for given channel.
C/C++ declaration
int PauseDDC1Playback(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_PAUSE_DDC1_PLAYBACK PauseDDC1Playback=(G39DDC_PAUSE_DDC1_PLAYBACK)dlsym(API,"PauseDDC1Playback");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If DDC1 playback is not active or it is already paused, PauseDDC1Playback does nothing.
The DDC1PlaybackStreamCallback and DDC1StreamCallback callback functions can be called once after PauseDDC1Playback returns. Then they are not called until playback is resumed using the ResumeDDC1Playback function.
Resumes paused DDC1 playback for given channel.
C/C++ declaration
int ResumeDDC1Playback(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_RESUME_DDC1_PLAYBACK ResumeDDC1Playback=(G39DDC_RESUME_DDC1_PLAYBACK)dlsym(API,"ResumeDDC1Playback");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If DDC1 playback is not active or it is not paused, ResumeDDC1Playback does nothing.
Retrieves number of DDC types supported by DDC2 for given channel.
C/C++ declaration
int GetDDC2Count(int32_t hDevice,uint32_t Channel,uint32_t *Count);
Address retrieval
G39DDC_GET_DDC2_COUNT GetDDC1Count=(G39DDC_GET_DDC2_COUNT)dlsym(API,"GetDDC1Count");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.Count[out] Pointer to a variable that receives number of DDC types. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Each channel has its own DDC2, see the block diagram. DDC type of each DDC2 can be different. Number of DDC types of DDC2 depends on DDC1 but maximum is 13 (DDC type index 12). If DDC type index of DDC1 is below 12, maximum of DDC types supported by DDC2 is DDC type index of DDC1 + 1. Changing of DDC type of DDC1 can cause change of DDC type of DDC2 and number of DDC types of DDC2, so it is useful to call GetDDC2 immediately after the SetDDC1 function to determine current DDC type of DDC2 if the application needs to know parameters of DDC2.
The BitsPerSample member of the G39DDC_DDC_INFO structure is not used and it can be ignored for DDC2. I and Q samples in buffers passed to the DDC2StreamCallback and DDC2PreprocessedStreamCallback DDC2 callback functions are always in IEEE float (32 bit, little endian) format.
Sets current DDC type of DDC2 for given channel.
C/C++ declaration
int SetDDC2(int32_t hDevice,uint32_t Channel,uint32_t DDCTypeIndex);
Address retrieval
G39DDC_SET_DDC2 SetDDC2=(G39DDC_SET_DDC2)dlsym(API,"SetDDC2");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are 0 and 1.DDCTypeIndex[in] Specifies index of DDC type to be used in DDC2.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetDDC2Count function to determine the number of possible DDC types of DDC2 for given channel. The DDCTypeIndex parameter can vary from zero to one less than the number determined by GetDDC2Count.
DDC2 streaming must not run when calling SetDDC2. In other words, DDC2 streaming that is started using the StartDDC2 function has to be stopped using the StopDDC2 function before calling of SetDDC2, otherwise SetDDC2 fails. The SetDDC2 function does not start and stop DDC2 streaming, just changes DDC type of DDC2.
Calling of SetDDC2 can change current bandwidth of demodulator filter, therefore it is useful to call the GetDemodulatorFilterBandwidth functions immediately after SetDDC2 to determine current bandwidth of demodulator filter.
Use the GetDDC2 function to determine current DDC type of the DDC2.
Retrieves information about current DDC type of the DDC2 for given channel.
C/C++ declaration
int GetDDC2(int32_t hDevice,uint32_t Channel,uint32_t *DDCTypeIndex);
Address retrieval
G39DDC_GET_DDC2 GetDDC2=(G39DDC_GET_DDC2)dlsym(API,"GetDDC2");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.DDCTypeIndex[out] Pointer to a variable that receives index of current DDC type of the DDC2. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Each channel has its own DDC2, see the block diagram. DDC type of DDC2 in each channel can be different. Number of provided DDC types for DDC2 depends on current DDC type of DDC1. Maximum number of DDC types for DDC2 is 13, maximum DDC type index for DDC2 is 12.
Chanding DDC type index of DDC1 (using the SetDDC1 function can cause change of number of supported DDC types and current DDC type index for DDC2. Therefore it is useful to call GetDDC2 and GetDDCInfo immediately after the SetDDC1 function.
Returned DDCTypeIndex can be passed to the GetDDCInfo function. The BitsPerSample member of the G39DDC_DDC_INFO structure is not used and it can be ignored for DDC2. I and Q samples in buffers passed to the DDC2StreamCallback and DDC2PreprocessedStreamCallback DDC2 callback functions are always in IEEE float (32 bit, little endian) format.
Sets relative center frequency of DDC2 for given channel.
C/C++ declaration
int SetDDC2Frequency(int32_t hDevice,uint32_t Channel,int32_t Frequency);
Address retrieval
G39DDC_SET_DDC2_FREQUENCY SetDDC2Frequency=(G39DDC_SET_DDC2_FREQUENCY)dlsym(API,"SetDDC2Frequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Frequency[in] Specifies new center frequency of DDC2 in Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Value of the Frequency parameter is center frequency of the DDC2 relative to center of the DDC1. The value can be negative.
Absolute frequency of the DDC2 is given by the following formula:
faDDC2[i] = fFE + frDDC1[i] + frDDC2[i]
Where faDDC2[i] is absolute center frequency of DDC2 of i-th channel in Hz, fFE is front-end frequency (see SetFrontEndFrequency), fDDC1[i] is relative center frequency of the DDC1 in Hz (set using the SetDDC1Frequency function) and frDDC2[i] is relative center frequency of DDC2 of i-th channel in Hz (set using SetDDC2Frequency).
Changing of DDC2 relative frequency changes absolute frequency of the DDC2 and demodulator in the specified channel.
Use the GetDDC2Frequency function to determine current relative center frequency of the DDC2 for given channel.
The following example shows how it is possible to set absolute DDC2 center frequency of channel 0 to 11.01 MHz:
int32_t hDevice; //Handle to G39DDC device returned by the OpenDevice function //1. method SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1000000); SetDDC2Frequency(hDevice,0,10000); //2. method SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1010000); SetDDC2Frequency(hDevice,0,0); //2. method SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1020000); SetDDC2Frequency(hDevice,0,-10000);
Retrieves current relative center frequency of DDC2.
C/C++ declaration
int GetDDC2Frequency(int32_t hDevice,uint32_t Channel,int32_t *Frequency);
Address retrieval
G39DDC_GET_DDC2_FREQUENCY GetDDC2Frequency=(G39DDC_GET_DDC2_FREQUENCY)dlsym(API,"GetDDC2Frequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Frequency[out] Pointer to a variable that receives current relative center frequency of DDC2 in Hz. The returned value can be negative. See remarks of the SetDDC2Frequency for information how to calculate absolute center frequency of DDC2. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Starts DDC2 streaming for given channel.
C/C++ declaration
int StartDDC2(int32_t hDevice,uint32_t Channel,uint32_t SamplesPerBuffer);
Address retrieval
G39DDC_START_DDC2 StartDDC2=(G39DDC_START_DDC2)dlsym(API,"StartDDC2");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.SamplesPerBuffer[in] Specifies number of I/Q sample sets in each buffer passed to the the DDC2StreamCallback and DDC2PreprocessedStreamCallback callback functions. The value has to be multiple of 64 greater than zero. If it is zero, the StartDDC2 function fails. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Before StartDDC2 is used, the G39DDC device has to be turned on using the SetPower function and DDC1 streaming has to be started using the StartDDC1 or StartDDC1Playback function, otherwise StartDDC2 fails.
If the DDC2 streaming for given channel is already running, StartDDC2 restarts it except the streaming was previously started with the same SamplesPerBuffer parameter. In this case StartDDC2 does nothing. Restart of the DDC2 streaming stops audio streaming for give channel. StartDDC2 does not restart audio streaming.
Use the StopDDC2 function to stop DDC2 streaming.
Decreasing value of the SamplesPerBuffer parameter decreases latency and it may increase CPU usage. Increasing value of the SamplesPerBuffer parameter increased latency and it may decrease CPU usage.
Stops DDC2 streaming for given channel.
C/C++ declaration
int StopDDC2(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_STOP_DDC2 StopDDC2=(G39DDC_STOP_DDC2)dlsym(API,"StopDDC2");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If audio streaming for given channel is running, it is stopped too.
If DDC2 streaming is not active, StopDDC2 does nothing.
The DDC2StreamCallback and DDC2PreprocessedStreamCallback callback functions are not called after StopDDC2 returns.
Enables or disables noise blanker on DDC2 stream for given channel.
C/C++ declaration
int SetDDC2NoiseBlanker(int32_t hDevice,uint32_t Channel,int Enabled);
Address retrieval
G39DDC_SET_DDC2_NOISE_BLANKER SetDDC2NoiseBlanker=(G39DDC_SET_DDC2_NOISE_BLANKER)dlsym(API,"SetDDC2NoiseBlanker");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Enabled[in] Specifies whether to enable or disable noise blanker. If this parameter is non-zero, noise blanker is enabled. If the parameter is zero, noise blanker is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetDDC2NoiseBlanker function to determine current state of the noise blanker.
Retrieves current DDC2 noise blanker state of given channel.
C/C++ declaration
int GetDDC2NoiseBlanker(int32_t hDevice,uint32_t Channel,int *Enabled);
Address retrieval
G39DDC_GET_DDC2_NOISE_BLANKER GetDDC2NoiseBlanker=(G39DDC_GET_DDC2_NOISE_BLANKER)dlsym(API,"GetDDC2NoiseBlanker");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Enabled[out] Pointer to a variable that receives current state of noise blanker. The value is non-zero if noise blanker is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies DDC2 noise blanker threshold for given channel.
C/C++ declaration
int SetDDC2NoiseBlankerThreshold(int32_t hDevice,uint32_t Channel,double Threshold);
Address retrieval
G39DDC_SET_DDC2_NOISE_BLANKER_THRESHOLD SetDDC2NoiseBlankerThreshold= (G39DDC_SET_DDC2_NOISE_BLANKER_THRESHOLD)dlsym(API,"SetDDC2NoiseBlankerThreshold");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Threshold[in] Specifies threshold in %.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetDDC2NoiseBlankerThreshold function to retrieve current threshold of the noise blanker.
Retrieves DDC2 noise blanker threshold of given channel.
C/C++ declaration
int GetDDC2NoiseBlankerThreshold(int32_t hDevice,uint32_t Channel,double *Threshold);
Address retrieval
G39DDC_GET_DDC2_NOISE_BLANKER_THRESHOLD GetDDC2NoiseBlankerThreshold= (G39DDC_GET_DDC2_NOISE_BLANKER_THRESHOLD)dlsym(API,"GetDDC2NoiseBlankerThreshold");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Threshold[out] Pointer to a variable that receives threshold of the noise blanker. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Determines value which indicates percentage ratio between short time average signal level and maximum level.
C/C++ declaration
int GetDDC2NoiseBlankerExcessValue(int32_t hDevice,uint32_t Channel,double *Value);
Address retrieval
G39DDC_GET_DDC2_NOISE_BLANKER_EXCESS_VALUE GetDDC2NoiseBlankerExcessValue= (G39DDC_GET_DDC2_NOISE_BLANKER_EXCESS_VALUE)dlsym(API,"GetDDC2NoiseBlankerExcessValue");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Value[out] Pointer to a variable that receives current excess value in %. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Determines current signal level for given channel.
C/C++ declaration
int GetSignalLevel(int32_t hDevice,uint32_t Channel,float *Peak,float *RMS);
Address retrieval
G39DDC_GET_SIGNAL_LEVEL GetSignalLevel=(G39DDC_GET_SIGNAL_LEVEL)dlsym(API,"GetSignalLevel");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Peak[out] Pointer to a variable that receives current signal level (peak) in Volts. This parameter can be NULL if the application does not require this information.RMS[out] Pointer to a variable that receives current signal level (RMS) in Volts. This parameter can be NULL if the application does not require this information.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
DDC2 streaming has to be active (started using the StartDDC2 function) before calling of GetSignalLevel, otherwise returned peak and RMS signal levels are zero.
Signal level is evaluated from signal after the demodulator filter and before the notch filter (see block diagram), the signal is selected by the demodulator filter.
Signal level is evaluated for each buffer that processed by the demoduletor filter. Buffer size (signal level evaluation rate) is given by the SamplesPerBuffer parameter of the StartDDC2 function.
The DDC2PreprocessedStreamCallback callback function provides signal level for each buffer passed the callback, i.e. for each buffer used in signal level evaluation. This provides way to get signal level from each processed buffer without need of pulling it using GetSignalLevel.
To convert RMS signal level in Volts to power in dBm use the following formulas:
P[W] = (VRMS)2 / R = (VRMS)2 / 50
P[dBm]= 10 * log10( P[W] * 1000 )
Where VRMS is RMS signal level in Volts obtained by GetSignalLevel, R is G39DDC receiver input impedance (50 Ω), P[W] is power in Watts, P[dBm] is power in dBm and 1000 is conversion coefficient W -> mW.
The following example shows how to obtain current signal level in dBm from channel 0:
#include <stdio.h> #include <math.h> int32_t hDevice; //handle to G39DDC device returned by the OpenDevice function float P_dBm,V_RMS; GetSignalLevel(hDevice,0,NULL,&V_RMS); P_dBm=10.0*log10(V_RMS*V_RMS*(1000.0/50.0)); printf("Current signal level [RMS]: %.1f dBm\n",P_dBm);
Enables or disables notch filter for given channel.
C/C++ declaration
int SetNotchFilter(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,int Enabled);
Address retrieval
G39DDC_SET_NOTCH_FILTER SetNotchFilter=(G39DDC_SET_NOTCH_FILTER)dlsym(API,"SetNotchFilter");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Enabled[in] Specifies whether to enable or disable notch filter. If this parameter is non-zero, the filter is enabled. If the parameter is zero, the filter is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetNotchFilter function to determine whether the filter is enabled or disabled.
Retrieves current notch filter state for given channel.
C/C++ declaration
int GetNotchFilter(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,int *Enabled);
Address retrieval
G39DDC_SET_NOTCH_FILTER SetNotchFilter=(G39DDC_SET_NOTCH_FILTER)dlsym(API,"SetNotchFilter");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Enabled[out] Pointer to a variable that receives current state of the notch filter. The value is non-zero if the filter is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies relative center frequency of the notch filter for given channel.
C/C++ declaration
int SetNotchFilterFrequency(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,int32_t Frequency);
Address retrieval
G39DDC_SET_NOTCH_FILTER_FREQUENCY SetNotchFilterFrequency= (G39DDC_SET_NOTCH_FILTER_FREQUENCY)dlsym(API,"SetNotchFilterFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Frequency[in] Specifies new center frequency of the notch filter in Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Value of the Frequency parameter is new center frequency of the notch filter relative to center of the DDC2 (see the SetDDC2Frequency function). The value can be negative.
Use the GetNotchFilterFrequency function to retrieve current center frequency of the notch filter.
Retrieves current relative center frequency of the notch filter.
C/C++ declaration
int GetNotchFilterFrequency(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,int32_t *Frequency);
Address retrieval
G39DDC_GET_NOTCH_FILTER_FREQUENCY GetNotchFilterFrequency= (G39DDC_GET_NOTCH_FILTER_FREQUENCY)dlsym(API,"GetNotchFilterFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Frequency[out] Pointer to a variable that receives current center frequency of the notch filter. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies bandwidth of the notch filter for given channel.
C/C++ declaration
int SetNotchFilterBandwidth(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,uint32_t Bandwidth);
Address retrieval
G39DDC_SET_NOTCH_FILTER_BANDWIDTH SetNotchFilterBandwidth= (G39DDC_SET_NOTCH_FILTER_BANDWIDTH)dlsym(API,"SetNotchFilterBandwidth");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Bandwidth[in] Specifies new bandwidth of the notch filter in Hz. The bandwidth can be from range 1 - 3000 Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetNotchFilterBandwidth function to retrieve current bandwidth of the notch filter.
Retrieves current bandwidth of the notch filter for given channel.
C/C++ declaration
int GetNotchFilterBandwidth(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,uint32_t *Bandwidth);
Address retrieval
G39DDC_GET_NOTCH_FILTER_BANDWIDTH GetNotchFilterBandwidth= (G39DDC_GET_NOTCH_FILTER_BANDWIDTH)dlsym(API,"GetNotchFilterBandwidth");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Bandwidth[out] Pointer to a variable that receives current bandwidth of the notch filter. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies notch filter length for given channel. The notch filter is implemented as FIR filter. This function specifies number of coefficients used in filtration procedure.
C/C++ declaration
int SetNotchFilterLength(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,uint32_t Length);
Address retrieval
G39DDC_SET_NOTCH_FILTER_LENGTH SetNotchFilterLength= (G39DDC_SET_NOTCH_FILTER_LENGTH)dlsym(API,"SetNotchFilterLength");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Length[in] Specifies length of the notch filter. The value has to be multiple of 64, greater than or equal to 64 and less than or equal to 32768. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Increasing the filter length increases filter steepness and it may increase CPU usage.
Use the GetNotchFilterLength function to determine current length of the notch filter.
Retrieves current notch filter length for given channel.
C/C++ declaration
int GetNotchFilterLength(int32_t hDevice,uint32_t Channel,uint32_t NotchFilterIndex,uint32_t *Length);
Address retrieval
G39DDC_GET_NOTCH_FILTER_LENGTH GetNotchFilterLength= (G39DDC_GET_NOTCH_FILTER_LENGTH)dlsym(API,"GetNotchFilterLength");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.NotchFilterIndex[in] Specifies notch filter index. Possible values are: 0, 1.Length[out] Pointer to a variable that receives current length of the notch filter. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Enables or disables AGC for given channel.
C/C++ declaration
int SetAGC(int32_t hDevice,uint32_t Channel,int Enabled);
Address retrieval
G39DDC_SET_AGC SetAGC=(G39DDC_SET_AGC)dlsym(API,"SetAGC");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Enabled[in] Specifies whether to enable or disable AGC. If this parameter is non-zero, the AGC is enabled. If the parameter is zero, the AGC is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If the AGC is disabled, the signal is affected by fixed gain specified using the SetGain function.
Use the GetAGC function to determine current state of the AGC.
Retrieves current state of the AGC for given channel.
C/C++ declaration
int GetAGC(int32_t hDevice,uint32_t Channel,int *Enabled);
Address retrieval
G39DDC_GET_AGC GetAGC=(G39DDC_GET_AGC)dlsym(API,"GetAGC");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Enabled[out] Pointer to a variable that receives current state of the AGC. The value is non-zero if the AGC is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets parameters of the AGC for given channel.
C/C++ declaration
int SetAGCParams(int32_t hDevice,uint32_t Channel,double AttackTime,double DecayTime,double ReferenceLevel);
Address retrieval
G39DDC_SET_AGC_PARAMS SetAGCParams=(G39DDC_SET_AGC_PARAMS)dlsym(API,"SetAGCParams");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.AttackTime[in] Specifies new attack time of the AGC in seconds.DecayTime[in] Specifies new decay time of the AGC in seconds.ReferenceLevel[in] Specifies new reference level of the AGC in dB.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetAGCParams function to determine current parameters of the AGC.
Retrieves current parameters of the AGC for given channel.
C/C++ declaration
int GetAGCParams(int32_t hDevice,uint32_t Channel,double *AttackTime,double *DecayTime,double *ReferenceLevel);
Address retrieval
G39DDC_GET_AGC_PARAMS GetAGCParams=(G39DDC_GET_AGC_PARAMS)dlsym(API,"GetAGCParams");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.AttackTime[out] Pointer to a variable that receives current attack time of the AGC in seconds. This parameter can be NULL if the application does not require this information.DecayTime[out] Pointer to a variable that receives current decay time of the AGC in seconds. This parameter can be NULL if the application does not require this information.ReferenceLevel[out] Pointer to a variable that receives current reference level of the AGC in dB. This parameter can be NULL if the application does not require this information.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets maximum gain of the AGC for given channel.
C/C++ declaration
int SetMaxAGCGain(int32_t hDevice,uint32_t Channel,double MaxGain);
Address retrieval
G39DDC_SET_MAX_AGC_GAIN SetMaxAGCGain=(G39DDC_SET_MAX_AGC_GAIN)dlsym(API,"SetMaxAGCGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.MaxGain[in] Specifies new maximum gain of the AGC in dB.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetMaxAGCGain function to determine maximum gain of the AGC.
Retrieves current maximum gain of the AGC for given channel.
C/C++ declaration
int GetMaxAGCGain(int32_t hDevice,uint32_t Channel,double *MaxGain);
Address retrieval
G39DDC_GET_MAX_AGC_GAIN GetMaxAGCGain=(G39DDC_GET_MAX_AGC_GAIN)dlsym(API,"GetMaxAGCGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.MaxGain[out] Pointer to a variable that receives current maximum gain of the AGC in dB. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets fixed gain for given channel. This gain is applied to I/Q signal if the AGC is disabled, otherwise it is not used.
C/C++ declaration
int SetGain(int32_t hDevice,uint32_t Channel,double Gain);
Address retrieval
G39DDC_SET_GAIN SetGain=(G39DDC_SET_GAIN)dlsym(API,"SetGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Gain[in] Specifies new fixed gain in dB.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetGain function to determine current fixed gain.
Retrieves current fixed gain for given channel.
C/C++ declaration
int GetGain(int32_t hDevice,uint32_t Channel,double *Gain);
Address retrieval
G39DDC_GET_GAIN GetGain=(G39DDC_GET_GAIN)dlsym(API,"GetGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Gain[out] Pointer to a variable that receives current fixed gain in dB. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Retrieves current gain that is applied to I/Q signal.
C/C++ declaration
int GetCurrentGain(int32_t hDevice,uint32_t Channel,double *CurrentGain);
Address retrieval
G39DDC_GET_CURRENT_GAIN GetCurrentGain=(G39DDC_GET_CURRENT_GAIN)dlsym(API,"GetCurrentGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.CurrentGain[out] Pointer to a variable that receives current gain in dB. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If the AGC is enabled (using the SetAGC function), the variable pointed to by the CurrentGain parameter is filled by current gain of the AGC. If the AGC is disabled, the variable pointed to by the CurrentGain parameter is filled by fixed gain that is specified using the SetGain function.
Sets bandwidth of the demodulator filter for given channel.
C/C++ declaration
int SetDemodulatorFilterBandwidth(int32_t hDevice,uint32_t Channel,uint32_t Bandwidth);
Address retrieval
G39DDC_SET_DEMODULATOR_FILTER_BANDWIDTH SetDemodulatorFilterBandwidth= (G39DDC_SET_DEMODULATOR_FILTER_BANDWIDTH)dlsym(API,"SetDemodulatorFilterBandwidth");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Bandwidth[in] Specified new bandwidth of the demodulator filter in Hz. Possible values are from range 1 Hz to current DDC2 bandwidth. Use the GetDDC2 and GetDDCInfo functions to retrieve information about current DDC type of DDC2.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The demodulator filter bandwidth can be changed using the SetDDC1 function. It can change DDC type of DDC2 and if the current demodulator filter bandwidth is greater than new bandwidth of DDC2, the demodulator filter bandwidth is reduced. So it is useful to call the GetDemodulatorFilterBandwidth function immediately after SetDDC1 and SetDDC2 functions.
Retrieves current demodulator filter bandwidth for given channel.
C/C++ declaration
int GetDemodulatorFilterBandwidth(int32_t hDevice,uint32_t Channel,uint32_t *Bandwidth);
Address retrieval
G39DDC_GET_DEMODULATOR_FILTER_BANDWIDTH GetDemodulatorFilterBandwidth= (G39DDC_GET_DEMODULATOR_FILTER_BANDWIDTH)dlsym(API,"GetDemodulatorFilterBandwidth");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Bandwidth[out] Pointer to a variable that receives current demodulator filter bandwidth. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets demodulator filter shift for given channel.
C/C++ declaration
int SetDemodulatorFilterShift(int32_t hDevice,uint32_t Channel,int32_t Shift);
Address retrieval
G39DDC_SET_DEMODULATOR_FILTER_SHIFT SetDemodulatorFilterShift= (G39DDC_SET_DEMODULATOR_FILTER_SHIFT)dlsym(API,"SetDemodulatorFilterShift");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Shift[in] Specified new shift of the demodulator filter in Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Value of the Shift parameter is shift in Hz relative to center of the demodulator. This value can be negative.
This function does not change demodulator frequency just shift the filter from demodulator's centre.
Use the GetDemodulatorFilterShift function to determine current demodulator filter shift.
Retrieves current shift of the demodulator filter for given channel.
C/C++ declaration
int GetDemodulatorFilterShift(int32_t hDevice,uint32_t Channel,int32_t *Shift);
Address retrieval
G39DDC_GET_DEMODULATOR_FILTER_SHIFT GetDemodulatorFilterShift= (G39DDC_GET_DEMODULATOR_FILTER_SHIFT)dlsym(API,"GetDemodulatorFilterShift");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Shift[out] Pointer to a variable that receives current shift of the demodulator. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies demodulator filter length for given channel. The demodulator filter is implemented as FIR filter. This function specifies number of coefficients used in filtration procedure..
C/C++ declaration
int SetDemodulatorFilterLength(int32_t hDevice,uint32_t Channel,uint32_t Length);
Address retrieval
G39DDC_SET_DEMODULATOR_FILTER_LENGTH SetDemodulatorFilterLength= (G39DDC_SET_DEMODULATOR_FILTER_LENGTH)dlsym(API,"SetDemodulatorFilterLength");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Length[in] Specifies length of the demodulator filter. The value has to be multiple of 64, greater than or equal to 64 and less than or equal to 32768. If it is not multiple of 64 the function rounds it up to nearest multiple of 64..
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Increasing the filter length increases filter steepness and it may increase CPU usage.
Use the GetDemodulatorFilterLength function to determine current length of the demodulator filter.
Retrieves current length of the demodulator filter for given channel.
C/C++ declaration
int GetDemodulatorFilterLength(int32_t hDevice,uint32_t Channel,uint32_t *Length);
Address retrieval
G39DDC_GET_DEMODULATOR_FILTER_LENGTH GetDemodulatorFilterLength= (G39DDC_GET_DEMODULATOR_FILTER_LENGTH)dlsym(API,"GetDemodulatorFilterLength");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Length[out] Pointer to a variable that receives current demodulator filter length. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets demodulator mode for given channel.
C/C++ declaration
int SetDemodulatorMode(int32_t hDevice,uint32_t Channel,uint32_t Mode);
Address retrieval
G39DDC_SET_DEMODULATOR_MODE SetDemodulatorMode=(G39DDC_SET_DEMODULATOR_MODE)dlsym(API,"SetDemodulatorMode");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Mode[in] Specifies new demodulator mode. This value can be one of the following:
Value Meaning G39DDC_MODE_CW Continuous wave G39DDC_MODE_AM Amplitude modulation G39DDC_MODE_FM Frequency modulation G39DDC_MODE_FMW Wide-band frequency modulation. G39DDC_MODE_LSB Lower sideband modulation G39DDC_MODE_USB Upper sideband modulation G39DDC_MODE_AMS Amplitude modulation G39DDC_MODE_DSB Double sideband modulation G39DDC_MODE_ISB Independent sideband modulation
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Different between FM and FMW modes is the FMW demodulator does stereo decoding and it is suitable for FM broadcasting. FMW mode is available only if DDC type index of DDC2 is 7 (bandwidth = 100 kHz, sample rate = 125 kHz) or above. SetDemodulatorMode fails trying to set FMW mode if DDC type index of DDC2 is less than 7. If current demodulator mode is FMW and DDC type index of DDC2 is changed to value below 7 (using SetDDC2 or SetDDC1 function), the mode is changed to FM.
Use the GetDemodulatorMode function to retrieve current demodulator mode.
Retrieves current demodulator mode for given channel.
C/C++ declaration
int GetDemodulatorMode(int32_t hDevice,uint32_t Channel,uint32_t *Mode);
Address retrieval
G39DDC_GET_DEMODULATOR_MODE GetDemodulatorMode=(G39DDC_GET_DEMODULATOR_MODE)dlsym(API,"GetDemodulatorMode");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Mode[out] Pointer to a variable that receives current demodulator mode. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets relative center frequency of demodulator for given channel.
C/C++ declaration
int SetDemodulatorFrequency(int32_t hDevice,uint32_t Channel,int32_t Frequency);
Address retrieval
G39DDC_SET_DEMODULATOR_FREQUENCY SetDemodulatorFrequency= (G39DDC_SET_DEMODULATOR_FREQUENCY)dlsym(API,"SetDemodulatorFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Frequency[in] Specified new center frequency of the demodulator in Hz.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Value of the Frequency parameter is center frequency of the demodulator relative to center of the DDC2. The value can be negative.
Absolute frequency of the demodulator is given by the following formula:
faDEM[i] = fFE + frDDC1[i] + frDDC2[i] + frDEM[i]
Where faDEM[i] is absolute center frequency of the demodulator of i-th channel in Hz, fFE is front-end frequency (see SetFrontEndFrequency), frDDC1[i] is relative center frequency of the DDC1 in Hz (set using the SetDDC1Frequency function), frDDC2[i] is relative center frequency of DDC2 of i-th channel in Hz (set using the SetDDC2Frequency) and frDEM[i] is relative center frequency of the demodulator of i-th channel in Hz (set using SetDemodulatorFrequency).
Absolute center frequency of the demodulator is the real-world frequency that you are listening to.
Use the GetDemodulatorFrequency function to determine current relative center frequency of the demodulator for given channel.
The following example shows four methods how it is possible to set absolute demodulator center frequency of channel 0 to 11.01 MHz:
int32_t hDevice; //Handle to G39DDC device returned by the OpenDevice function //1. method SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1010000); SetDDC2Frequency(hDevice,0,0); SetDemodulatorFrequency(hDevice,0,0); //2. method SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1000000); SetDDC2Frequency(hDevice,0,10000); SetDemodulatorFrequency(hDevice,0,0); //3. method SetFrontEndFrequency(hDevice,10000000); SetDDC1Frequency(hDevice,0,1000000); SetDDC2Frequency(hDevice,0,20000); SetDemodulatorFrequency(hDevice,0,-10000); //4. method SetFrequency(hDevice,11010000);
Retrieves current relative center frequency of the demodulator for given channel.
C/C++ declaration
int GetDemodulatorFrequency(int32_t hDevice,uint32_t Channel,int32_t *Frequency);
Address retrieval
G39DDC_GET_DEMODULATOR_FREQUENCY GetDemodulatorFrequency= (G39DDC_GET_DEMODULATOR_FREQUENCY)dlsym(API,"GetDemodulatorFrequency");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Frequency[out] Pointer to a variable that receives current center frequency of the demodulator. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets a parameter of the demodulation for given channel.
C/C++ declaration
int SetDemodulatorParam(int32_t hDevice,uint32_t Channel,uint32_t Code,const void *Buffer,uint32_t BufferSize);
Address retrieval
G39DDC_SET_DEMODULATOR_PARAM SetDemodulatorParam= (G39DDC_SET_DEMODULATOR_PARAM)dlsym(API,"SetDemodulatorParam");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Code[in] Specifies code of the demodulator parameter to be set by the function. The code can be one of the following:
Value Meaning G39DDC_DEMODULATOR_PARAM_AMS_SIDE_BAND Side band for synchronous AM demodulation.
The Buffer parameter has to be pointer to an uint32_t variable, and the BufferSize parameter has to be sizeof(uint32_t).
Value of the variable pointed to by the Buffer parameter can be one of the following:
G39DDC_SIDE_BAND_LOWER
AMS demodulator will use lower sidebandG39DDC_SIDE_BAND_UPPER
AMS demodulator will use upper sidebandG39DDC_SIDE_BAND_BOTH
AMS demodulator will use both side bands.G39DDC_DEMODULATOR_PARAM_AMS_CAPTURE_RANGE Capture range of synchronous AM demodulator.
The Buffer parameter has to be pointer to a G39DDC_AMS_CAPTURE_RANGE structure, and the BufferSize parameter has to be sizeof(G39DDC_AMS_CAPTURE_RANGE).
G39DDC_DEMODULATOR_PARAM_CW_FREQUENCY CW tone frequency
The Buffer parameter has to be pointer to a int32_t variable, and the BufferSize parameter has to be sizeof(int32_t).
Value of the variable pointed to by the Buffer parameter is CW tone frequency in Hz.
G39DDC_DEMODULATOR_PARAM_DSB_SIDE_BAND Side band for DSB demodulation.
The Buffer parameter has to be pointer to an uint32_t variable, and the BufferSize parameter has to be sizeof(uint32_t).
Value of the variable pointed to by the Buffer parameter can be one of the following:
G39DDC_SIDE_BAND_LOWER
DSB demodulator will use lower sidebandG39DDC_SIDE_BAND_UPPER
DSB demodulator will use upper sidebandG39DDC_SIDE_BAND_BOTH
DSB demodulator will use both side bands.G39DDC_DEMODULATOR_PARAM_ISB_SIDE_BAND Side band for ISB demodulation.
The Buffer parameter has to be pointer to an uint32_t variable, and the BufferSize parameter has to be sizeof(uint32_t).
Value of the variable pointed to by the Buffer parameter can be one of the following:
G39DDC_SIDE_BAND_LOWER
ISB demodulator will use lower sidebandG39DDC_SIDE_BAND_UPPER
ISB demodulator will use upper sidebandG39DDC_SIDE_BAND_BOTH
ISB demodulator will use both side bands.G39DDC_DEMODULATOR_PARAM_FMW_STEREO Stereo switch of FMW demodulator
The Buffer parameter has to be pointer to a int variable, and the BufferSize parameter has to be sizeof(int).
Value of the variable pointed to by the Buffer parameter is non-zero to enable stereo decoder, zero to disable stereo decoder.
G39DDC_DEMODULATOR_PARAM_FMW_DEEMPHASIS De-emphasis (FMW demodulator)
The Buffer parameter has to be pointer to a uint32_t variable, and the BufferSize parameter has to be sizeof(uint32_t).
Value of the variable pointed to by the Buffer parameter is de-emphasis at demodulator audio output in µs. In North America it is 75 µs, while most of the rest of the world uses 50 µs. If it is zero, the de-emphasis is disabled.
Buffer[in] Pointer to a buffer containing value of the demodulator parameter the function will set. This parameter cannot be NULL.BufferSize[in] Specifies the size of the buffer.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Retrieves a parameter of the demodulation for given channel.
C/C++ declaration
int GetDemodulatorParam(int32_t hDevice,uint32_t Channel,uint32_t Code,void *Buffer,uint32_t BufferSize);
Address retrieval
G39DDC_GET_DEMODULATOR_PARAM GetDemodulatorParam= (G39DDC_GET_DEMODULATOR_PARAM)dlsym(API,"GetDemodulatorParam");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Code[in] Specifies code of the demodulator parameter to be retrieved. For detailed information about available codes see SetDemodulatorParam.Buffer[out] Pointer to a buffer that receives requested parameter. This parameter cannot be NULL.BufferSize[in] Specifies the size of the buffer.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Retrieves information about current demodulator state for given channel.
C/C++ declaration
int GetDemodulatorState(int32_t hDevice,uint32_t Channel,uint32_t Code,void *Buffer,uint32_t BufferSize);
Address retrieval
G39DDC_GET_DEMODULATOR_STATE GetDemodulatorState= (G39DDC_GET_DEMODULATOR_STATE)dlsym(API,"GetDemodulatorState");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Code[in] Specifies code of the demodulator state to be retrieved. It can be one of the following:
Value Meaning G39DDC_DEMODULATOR_STATE_AMS_LOCK Lock state of synchronous AM demodulation.
The Buffer parameter has to be pointer to a int variable, and the BufferSize parameter has to be sizeof(int).
Received value is non-zero if synchronous AM demodulator is locked to signal, and zero if it is not locked.
G39DDC_DEMODULATOR_STATE_AMS_FREQUENCY Frequency in Hz which synchronous AM demodulator is locked to. It is relative to center of the demodulator. It can be negative.
The Buffer parameter has to be pointer to a double variable, and the BufferSize parameter has to be sizeof(double).
G39DDC_DEMODULATOR_STATE_AM_DEPTH Depth of AM modulation in %.
The Buffer parameter has to be pointer to a double variable, and the BufferSize parameter has to be sizeof(double).
G39DDC_DEMODULATOR_STATE_DSB_LOCK Lock state of DSB demodulation.
The Buffer parameter has to be pointer to a int variable, and the BufferSize parameter has to be sizeof(int).
Received value is non-zero if DSB demodulator is locked to signal, and zero if it is not locked.
G39DDC_DEMODULATOR_STATE_DSB_FREQUENCY Frequency in Hz which DSB demodulator is locked to. It is relative to center of the demodulator. It can be negative.
The Buffer parameter has to be pointer to a double variable, and the BufferSize parameter has to be sizeof(double).
G39DDC_DEMODULATOR_STATE_TUNE_ERROR Estimated tune error in Hz.
The Buffer parameter has to be pointer to an int32_t variable, and the BufferSize parameter has to be sizeof(int32_t).
Received value is difference between demodulator frequency and frequency of received signal. Subtract the returned tune error from demodulator frequency to get frequency of the received signal. Tune error is relative to center of the demodulator and it can be negative.
G39DDC_DEMODULATOR_STATE_FM_DEVIATION Estimated frequency deviation in Hz.
The Buffer parameter has to be pointer to an uint32_t variable, and the BufferSize parameter has to be sizeof(uint32_t).
G39DDC_DEMODULATOR_STATE_FMW_STEREO State of FMW stereo decoder.
The Buffer parameter has to be pointer to a int variable, and the BufferSize parameter has to be sizeof(int).
Received value is non-zero if received signal is stereo (stereo pilot detected), and zero if it is not stereo (stereo pilot is not detected).
Buffer[out] Pointer to a buffer that receives requested information. This parameter cannot be NULL.BufferSize[in] Specifies the size of the buffer.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Retrieves number of audio sample rates supported by the G39DDC.
C/C++ declaration
int GetAudioSampleRateCount(int32_t hDevice,uint32_t *Count);
Address retrieval
G39DDC_GET_AUDIO_SAMPLE_RATE_COUNT GetAudioSampleRateCount= (G39DDC_GET_AUDIO_SAMPLE_RATE_COUNT)dlsym(API,"GetAudioSampleRateCount");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Count[out] Pointer to a variable that receives number of audio sample rates supported by the G39DDC. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Retrieves audio sample rate by its index.
C/C++ declaration
int GetAudioSampleRate(int32_t hDevice,uint32_t Index,uint32_t *SampleRate);
Address retrieval
G39DDC_GET_AUDIO_SAMPLE_RATE GetAudioSampleRate= (G39DDC_GET_AUDIO_SAMPLE_RATE)dlsym(API,"GetAudioSampleRate");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Index[in] Specifies audio sample rate index. This value can vary from 0 to value retrieved by the GetAudioSampleRateCount - 1.SampleRate[out] Pointer to a variable that receives audio sample rate. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets output audio sample rate.
C/C++ declaration
int SetAudio(int32_t hDevice,uint32_t Channel,uint32_t Index);
Address retrieval
G39DDC_SET_AUDIO SetAudio=(G39DDC_SET_AUDIO)dlsym(API,"SetAudio");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Index[in] Specifies audio sample rate index.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetAudioSampleRateCount function to determine the number of possible audio sample rates. The Index parameter can vary from zero to one less than the number determined by GetAudioSampleRateCount.
Audio streaming must not run when calling SetAudio. In other words, audio streaming that is started using the StartAudio function has to be stopped using the StopAudio function before calling of SetAudio, otherwise SetAudio fails. The SetAudio function does not start and stop audio streaming, just changes current audio sample rate.
Use the GetAudio function to determine current audio sample rate index and use the GetAudioSampleRate to convert the index to sample rate.
Retrieves audio sample rate index.
C/C++ declaration
int GetAudio(int32_t hDevice,uint32_t Channel,uint32_t *SampleRateIndex);
Address retrieval
G39DDC_GET_AUDIO GetAudio=(G39DDC_GET_AUDIO)dlsym(API,"GetAudio");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.SampleRate[out] Pointer to a variable that receives current audio sample rate index. This parameter cannot be NULL. Use GetAudioSampleRate function to convert the index to sample rate.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Starts audio streaming for given channel.
C/C++ declaration
int StartAudio(int32_t hDevice,uint32_t Channel,uint32_t SamplesPerBuffer);
Address retrieval
G39DDC_START_AUDIO StartAudio=(G39DDC_START_AUDIO)dlsym(API,"StartAudio");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.SamplesPerBuffer[in] Specifies number of samples in each buffer passed to the the AudioStreamCallback callback function. The value has to be multiple of 64 greater than zero. If it is zero, the StartAudio function fails. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Before StartAudio is used, the G39DDC device has to be turned on using the SetPower function and DDC1 streaming has to be started using the StartDDC1 or StartDDC1Playback function and DDC2 streaming has to be started using the StartDDC2 function, otherwise StartAudio fails.
If the audio streaming for given channel is already running, StartAudio restarts it except the streaming was previously started with the same SamplesPerBuffer parameter. In this case StartAudio does nothing.
Use the StopAudio function to stop audio streaming.
Decreasing value of the SamplesPerBuffer parameter decreases latency and it may increase CPU usage. Increasing value of the SamplesPerBuffer parameter increased latency and it may decrease CPU usage.
Stops audio streaming for given channel.
C/C++ declaration
int StopAudio(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_STOP_AUDIO StopAudio=(G39DDC_STOP_AUDIO)dlsym(API,"StopAudio");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If audio streaming is not active, StopAudio does nothing.
If audio playback (started using the StartAudioPlayback function) is active, StopAudio stops it.
The AudioStreamCallback and AudioPlaybackStreamCallback callback functions are not called after StopAudio returns.
Starts audio playback for given channel. It allows to pass previously recorded audio samples to the processing chain instead of the samples from the demodulator.
C/C++ declaration
int StartAudioPlayback(int32_t hDevice,uint32_t Channel,uint32_t SamplesPerBuffer);
Address retrieval
G39DDC_START_AUDIO_PLAYBACK StartAudioPlayback=(G39DDC_START_AUDIO_PLAYBACK)dlsym(API,"StartAudioPlayback");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.SamplesPerBuffer[in] Specifies number of samples in each buffer passed to the AudioPlaybackStreamCallback callback to fill the buffer by the application and to the AudioStreamCallback callback function. The value has to be multiple of 64 greater than zero. If it is zero, the StartAudioPlayback function fails. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using SetPower function before use of StartAudioPlayback.
The StartAudioPlayback function stops audio streaming that was previously started by the StartAudio or StartAudioPlayback function and starts audio playback with new parameters.
Use the StopAudio function to stop audio playback.
Pauses audio playback for given channel.
C/C++ declaration
int PauseAudioPlayback(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_PAUSE_AUDIO_PLAYBACK PauseAudioPlayback=(G39DDC_PAUSE_AUDIO_PLAYBACK)dlsym(API,"PauseAudioPlayback");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If audio playback is not active or it is already paused, PauseAudioPlayback does nothing.
The AudioPlaybackStreamCallback and AudioStreamCallback callback functions can be called once after PauseAudioPlayback returns. Then they are not called until playback is resumed using the ResumeAudioPlayback function.
Resumes paused audio playback for given channel.
C/C++ declaration
int ResumeAudioPlayback(int32_t hDevice,uint32_t Channel);
Address retrieval
G39DDC_RESUME_AUDIO_PLAYBACK ResumeAudioPlayback=(G39DDC_RESUME_AUDIO_PLAYBACK)dlsym(API,"ResumeAudioPlayback");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If audio playback is not active or it is not paused, ResumeAudioPlayback does nothing.
Sets fixed audio gain for given channel.
C/C++ declaration
int SetAudioGain(int32_t hDevice,uint32_t Channel,double Gain);
Address retrieval
G39DDC_SET_AUDIO_GAIN SetAudioGain=(G39DDC_SET_AUDIO_GAIN)dlsym(API,"SetAudioGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Gain[in] Specifies new fixed audio gain in dB.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If the G39DDC receiver has audio output connector (optional), the SetAudioGain function affects the audio signal level at this output (see also SetDAC).
Use the GetAudioGain function to retrieve current audio gain.
Retrieves current fixed audio gain for given channel.
C/C++ declaration
int GetAudioGain(int32_t hDevice,uint32_t Channel,double *Gain);
Address retrieval
G39DDC_GET_AUDIO_GAIN GetAudioGain=(G39DDC_GET_AUDIO_GAIN)dlsym(API,"GetAudioGain");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Gain[out] Pointer to a variable that receives current fixed gain in dB. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Enabled or disables audio filter for given channel.
C/C++ declaration
int SetAudioFilter(int32_t hDevice,uint32_t Channel,int Enabled);
Address retrieval
G39DDC_SET_AUDIO_FILTER SetAudioFilter=(G39DDC_SET_AUDIO_FILTER)dlsym(API,"SetAudioFilter");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Enabled[in] Specifies whether to enable or disable audio filter. If this parameter is non-zero, the filter is enabled. If the parameter is zero, the filter is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetAudioFiler function to retrieve current state of the audio filter.
Retrieves current state of the audio filter for given channel.
C/C++ declaration
int GetAudioFilter(int32_t hDevice,uint32_t Channel,int *Enabled);
Address retrieval
G39DDC_GET_AUDIO_FILTER GetAudioFilter=(G39DDC_GET_AUDIO_FILTER)dlsym(API,"GetAudioFilter");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Enabled[out] Pointer to a variable that receives current state of the audio filter. The value is non-zero if the filter is enabled and zero if it is disabled. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets parameters of the audio filter for given channel.
C/C++ declaration
int SetAudioFilterParams(int32_t hDevice,uint32_t Channel,uint32_t CutOffLow,uint32_t CutOffHigh,double Deemphasis);
Address retrieval
G39DDC_SET_AUDIO_FILTER_PARAMS SetAudioFilterParams= (G39DDC_SET_AUDIO_FILTER_PARAMS)dlsym(hAPI,"SetAudioFilterParams");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.CutOffLow[in] Specifies cut-off low frequency of the filter in Hz. This is the start frequency of filter's passband. The value has to be less then the cut-off high frequency specified by the CutOffHigh parameter.CutOffHigh[in] Specifies cut-off high frequency of the filter in Hz. This is the end frequency of filter's passband. The value has to be greater than the cut-off low frequency specified by the CutOffLow parameter.Deemphasis[in] Specifies de-emphasis the filter in dB per octave. De-emphasis starts at cut-off low frequency of the filter. This value can be from range -9.9 to 0.0 dB/octave. Zero means the de-emphasis is disabled.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Use the GetAudioFilerParams function to retrieve current parameters of the audio filter.
Retrieves current parameters of the audio filter for given channel.
C/C++ declaration
int GetAudioFilterParams(int32_t hDevice,uint32_t Channel,uint32_t *CutOffLow,uint32_t *CutOffHigh,double *Deemphasis);
Address retrieval
G39DDC_GET_AUDIO_FILTER_PARAMS GetAudioFilterParams= (G39DDC_GET_AUDIO_FILTER_PARAMS)dlsym(API,"GetAudioFilterParams");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.CutOffLow[out] Pointer to a variable that receives current cut-off low frequency of the filter. This parameter can be NULL if the application does not require this information.CutOffHigh[out] Pointer to a variable that receives current cut-off high frequency of the filter. This parameter can be NULL if the application does not require this information.Deemphasis[out] Pointer to a variable that receives current de-emphasis setting of the filter. This parameter can be NULL if the application does not require this information.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Specifies audio filter length for given channel. The audio filter is implemented as FIR filter. This function specifies number of coefficients used in filtration procedure.
C/C++ declaration
int SetAudioFilterLength(int32_t hDevice,uint32_t Channel,uint32_t Length);
Address retrieval
G39DDC_SET_AUDIO_FILTER_LENGTH SetAudioFilterLength= (G39DDC_SET_AUDIO_FILTER_LENGTH)dlsym(API,"SetAudioFilterLength");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Length[in] Specifies length of the audio filter. The value has to be multiple of 64, greater than or equal to 64 and less than or equal to 32768. If it is not multiple of 64 the function rounds it up to nearest multiple of 64.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
Increasing the filter length increases filter steepness and it may increase CPU usage.
Use the GetAudioFilterLength function to determine current length of the audio filter.
Retrieves current audio filter length for given channel.
C/C++ declaration
int GetAudioFilterLength(int32_t hDevice,uint32_t Channel,uint32_t *Length);
Address retrieval
G39DDC_GET_AUDIO_FILTER_LENGTH GetAudioFilterLength= (G39DDC_GET_AUDIO_FILTER_LENGTH)dlsym(API,"GetAudioFilterLength");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Length[out] Pointer to a variable that receives current length of the audio filter. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Sets audio volume for given channel.
C/C++ declaration
int SetVolume(int32_t hDevice,uint32_t Channel,uint8_t Volume);
Address retrieval
G39DDC_SET_VOLUME SetVolume=(G39DDC_SET_VOLUME)dlsym(API,"SetVolume");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Volume[in] Specifies new volume. The value can vary from 0 to 31, where 31 means maximum volume.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If the G39DDC receiver has audio output connector (optional), the SetVolume function affects the audio signal level at this output (see also SetDAC).
Use the GetVolume function to retrieve current volume.
Retrieve current volume for given channel.
C/C++ declaration
int GetVolume(int32_t hDevice,uint32_t Channel,uint8_t *Volume);
Address retrieval
G39DDC_GET_VOLUME GetVolume=(G39DDC_GET_VOLUME)dlsym(API,"GetVolume");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Volume[out] Pointer to a variable that receives current volume. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Mutes or unmutes audio.
C/C++ declaration
int SetMute(int32_t hDevice,uint32_t Channel,int Mute);
Address retrieval
G39DDC_SET_MUTE SetMute=(G39DDC_SET_MUTE)dlsym(API,"SetMute");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Mute[in] Specifies whether to mute or unmute audio. If this parameter is non-zero, the audio is muted. If the parameter is zero, the audio is unmuted.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If the G39DDC receiver has audio output connector (optional), the SetMute function affects the audio signal at this output (see also SetDAC).
Use the GetMute function to retrieve current mute state.
Retrieves current mute state for given channel.
C/C++ declaration
int GetMute(int32_t hDevice,uint32_t Channel,int *Mute);
Address retrieval
G39DDC_GET_MUTE GetMute=(G39DDC_GET_MUTE)dlsym(API,"GetMute");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. Possible values are: 0, 1.Mute[out] Pointer to a variable that receives current mute state. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Allows to route audio output of each channel to DAC (Digital-to-analog converter). DAC output is connected to audio output connector of the receiver.
C/C++ declaration
int SetDAC(int32_t hDevice,uint32_t DAC);
Address retrieval
G39DDC_SET_DAC SetDAC=(G39DDC_SET_DAC)dlsym(API,"SetDAC");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.DAC[in] Specifies which channel should be routed to the audio output connector.
Bit Meaning 0 If it is set, audio output of the channel 0 is routed to the audio output connector. 1 If it is set, audio output of the channel 1 is routed to the audio output connector. 2 - 31 Reserved. Must be zero. If both bits (0 and 1) are set, audio outputs of both channels are mixed and routed to the audio output connector.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The audio output connector is optional. If the receiver does not have audio output connector, SetDAC fails. The following example shows how to determine the receive has audio output connector.
G39DDC_DEVICE_INFO DeviceInfo; int32_t hDevice; //handle to open G39DDC device GetDeviceInfo(hDevice,&DeviceInfo,sizeof(DeviceInfo)); if(DeviceInfo.HardwareOptions & G39DDC_HARDWARE_OPTIONS_AUDIO_OUTPUT) { //the receiver has audio output connector //route audio output of both channels to the audio output connector SetDAC(hDevice,0x01 | 0x02); } else { //the receiver does not have audio output connector }
Determines which channel (its audio output) is routed to audio output connector.
C/C++ declaration
int GetDAC(int32_t hDevice,uint32_t *DAC);
Address retrieval
G39DDC_GET_DAC GetDAC=(G39DDC_GET_DAC)dlsym(API,"GetDAC");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.DAC[out] Pointer to a variable that receives bitwise array which specifies which channel is routed to the audio output connector. For more information, see SetDAC. This parameter cannot be NULL.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Starts sweeping.
C/C++ declaration
int StartSweeping(int32_t hDevice,uint64_t BeginFrequency,uint64_t EndFrequency,uint64_t StartFrequency,uint16_t SettlingTime,int Forward);
Address retrieval
G39DDC_START_SWEEPING StartSweeping=(G39DDC_START_SWEEPING)dlsym(API,"StartSweeping");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.BeginFrequency[in] Specifies the start frequency of the sweeping range in Hz.EndFrequency[in] Specifies the end frequency of the sweeping range in Hz.StartFrequency[in] Specifies the frequency to start sweeping from. It must be between (including) BeginFrequency and EndFrequency. Use the same value as for BeginFrequency to start sweeping from the beginning of the sweeping range.SettlingTime[in] The settling time in milliseconds. It is minimum delay time after tuning before the signal snapshot is taken. The value can vary from 1 to 1023 milliseconds.Forward[in] Specifies sweeping direction. If the value is non-zero, the sweeping runs in loop from the BeginFrequency to the EndFrequency. If the value is zero, the sweeping runs in loop from the EndFrequency to BeginFrequency.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using the SetPower function before StartSweeping is used, otherwise StartSweeping fails.
DDC1 streaming (StartDDC1) in each channel and IF snapshots (StartIF) must not be running before StartSweeping is used, otherwise StartSweeping fails.
When the sweeping runs, the receiver is tuned sequentially to frequencies from range specified by the BeginFrequency and EndFrequency parameters. The tuning direction is given by the Forward parameter. Tuning step is specified by the FrontEndFrequencyStep member of the G39DDC_DEVICE_INFO structure (see GetDeviceInfo).
The BeginFrequency has to be less than the EndFrequency.
The BeginFrequency and EndFrequency can be between (including) values provided by the FrontEndMinFrequency and FrontEndMaxFrequency members of the G39DDC_DEVICE_INFO structure.
If value of the BeginFrequency, EndFrequency or StartFrequency is not equal to the FrontEndMinFrequency member of G39DDC_DEVICE_INFO structure, it has to be multiple of the FrontEndFrequencyStep member of G39DDC_DEVICE_INFO structure.
The SweepingCallback callback is invoked once for each tuned frequency to pass the IF snapshot to the application during sweeping. Each snapshot consists of 65536 samples.
To use extended sweeping parameters in addition to parameters supported by StartSweeping, use the StartSweepingEx function.
StartSweeping(hDevice,BeginFrequency,EndFrequency,StartFrequency,SettlingTime,Forward) is equivalent to StartSweepingEx(hDevice,BeginFrequency,EndFrequency,StartFrequency,SettlingTime,Forward,0,0).
Use StopSweeping function to stop sweeping.
Starts sweeping.
C/C++ declaration
int StartSweepingEx(int32_t hDevice,uint64_t BeginFrequency,uint64_t EndFrequency,uint64_t StartFrequency,uint16_t SettlingTime,int Forward,uint32_t Repeat,int LargeIfBuffer);
Address retrieval
G39DDC_START_SWEEPING_EX StartSweepingEx=(G39DDC_START_SWEEPING_EX)dlsym(API,"StartSweepingEx");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.BeginFrequency[in] Specifies the start frequency of the sweeping range in Hz.EndFrequency[in] Specifies the end frequency of the sweeping range in Hz.StartFrequency[in] Specifies the frequency to start sweeping from. It must be between (including) BeginFrequency and EndFrequency. Use the same value as for BeginFrequency to start sweeping from the beginning of the sweeping range.SettlingTime[in] The settling time in milliseconds. It is minimum delay time after tuning before the signal snapshot is taken. The value can vary from 1 to 1023 milliseconds.Forward[in] Specifies sweeping direction. If the value is non-zero, the sweeping runs in loop from the BeginFrequency to the EndFrequency. If the value is zero, the sweeping runs in loop from the EndFrequency to BeginFrequency.Repeat[in] Specifies how many snapshots will be taken in addition at the same front-end frequency in intervals given by the SettlingTime parameter. If this parameter is zero, single snapshot is taken on each tuned front-end frequency. If this parameter is non-zero Repeat+1 snapshots are taken at the same front-end frequency each SettlingTime interval. It can be useful for frequency spectrum averaging during sweeping.LargeIfBuffer[in] Specifies number of samples in each IF snapshot during sweeping. If the value is zero, each snapshot consists of 65536 samples. If the value is non-zero, the snapshot consists of 262144 samples. Large snapshots can be useful for precise frequency spectrum during sweeping
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using the SetPower function before StartSweepingEx is used, otherwise StartSweepingEx fails.
DDC1 streaming (StartDDC1) in each channel and IF snapshots (StartIF) must not be running before StartSweepingEx is used, otherwise StartSweepingEx fails.
When the sweeping runs, the receiver is tuned sequentially to frequencies from range specified by the BeginFrequency and EndFrequency parameters. The tuning direction is given by the Forward parameter. Tuning step is specified by the FrontEndFrequencyStep member of the G39DDC_DEVICE_INFO structure (see GetDeviceInfo).
The BeginFrequency has to be less than the EndFrequency.
The BeginFrequency and EndFrequency can be between (including) values provided by the FrontEndMinFrequency and FrontEndMaxFrequency members of the G39DDC_DEVICE_INFO structure.
If value of the BeginFrequency, EndFrequency or StartFrequency is not equal to the FrontEndMinFrequency member of G39DDC_DEVICE_INFO structure, it has to be multiple of the FrontEndFrequencyStep member of G39DDC_DEVICE_INFO structure.
The SweepingCallback callback is invoked N times for each tuned frequency to pass the IF snapshot to the application during sweeping, where N = Repeat + 1. Time interval between repeated snapshots is equal to SettlingTime.
Use StopSweeping function to stop sweeping.
When the SettlingTime is very short (below 20 ms) the sweeping can be significantly slower with the LargeIfBuffer set to non-zero value than sweeping with the LargeIfBuffer set to zero. More time is required to make and transfer large snapshot to system memory.
Stops sweeping previously started using the StartSweeping function.
C/C++ declaration
int StopSweeping(int32_t hDevice);
Address retrieval
G39DDC_STOP_SWEEPING StopSweeping=(G39DDC_STOP_SWEEPING)dlsym(API,"StopSweeping");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Determines compensation data for frequency spectrum computed from DDC1 or DDC2 signal. It is used to convert relative amplitudes in dB to absolutes ones in dBm.
C/C++ declaration
int GetSpectrumCompensation(int32_t hDevice,uint64_t FrontEndFrequency,int32_t Shift,uint32_t Bandwidth,float *Buffer,uint32_t Count);
Address retrieval
G39DDC_GET_SPECTRUM_COMPENSATION GetSpectrumCompensation= (G39DDC_GET_SPECTRUM_COMPENSATION)dlsym(API,"GetSpectrumCompensation");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.FrontEndFrequency[in] Specifies front-end frequency in Hz.Shift[in] Specifies relative center frequency (in Hz) of the bandwidth given by the Bandwidth parameter. It is relative to front-end frequency given by the FrontEndFrequency parameter. It can be negative.Bandwidth[in] Specifies width of requested compensation data in Hz.Buffer[out] Pointer to a buffer to be filled with compensation data. This parameter cannot be NULL.Count[in] Specifies number of float items in the buffer pointed to by the Buffer parameter.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The following example shows how to use the GetSpectrumCompensation function in DDC2StreamCallback callback function:
//Let the following is prototype of a function which compute FFT from I/Q signal stored in //the buffer pointed to be the Input parameter. Result is stored in complex form in the buffer //pointed to by the Output parameter. Size of the FFT is given be the Size parameter. //The example uses FFT with size 2048. void FFT(float *Output,const float *Input,int Size); #define FFT_SIZE 2048 int32_t hDevice; //handle to G39DDC device uint64_t FrontEndFrequency; //Front-end frequency int32_t RelDDC2Frequency; //Relative frequency of the DDC2 int32_t RelDDC1Frequency; //Relative frequency of the DDC1 int32_t DDC2Shift; //Total shift of DDC2 from front-end frequency G39DDC_DDC_INFO DDC2Info; //Information about current DDC type of the DDC2 float FFTBuffer[2*FFT_SIZE]; //Buffer for FFT result float Compensation[FFT_SIZE]; //Buffer for compensation data uint32_t FirstBin,LastBin; //the first and last bins in the FFT of useful DDC2 band G39DDC_CALLBACKS Callbacks; //Structure which contains pointer to callback functions Code before... //Retrieve front-end frequency GetFrontEndFrequency(hDevice,&FrontEndFrequency); //Retrieve relative frequency of the DDC1 for channel 0 GetDDC1Frequency(hDevice,0,&RelDDC1Frequency); //Retrieve relative frequency of the DDC2 for channel 0 GetDDC2Frequency(hDevice,0,&RelDDC2Frequency); //Calculate DDC2 shift DDC2Shift=RelDDC2Frequency+RelDDC1Frequency; //Retrieve DDC type information of the DDC2 GetDDC2(hDevice,NULL,&DDC2Info); //Retrieve compensation data GetSpectrumCompensation(hDevice,FrontEndFrequency,DDC2Shift,DDC2Info.SampleRate,Compensation,FFT_SIZE); //In this case the Bandwidth parameter is equal to sample rate, because we need compensation data //for whole DDC2 band not only for usable bandwidth. //Compensation data have to be updated after change of absolute DDC2 frequency using //the SetDDC1Frequency, SetDDC2Frequency or SetFrontEndFrequency function. //In this case a mutual-exclusion synchronization method (for example critical section) should be used //if the Compensation buffer would be modified outside the MyDDC2StreamCallback callback. FirstBin=FFT_SIZE*(DDC2Info.SampleRate-DDC2Info.Bandwidth)/2/DDC2Info.SampleRate; LastBin=FFT_SIZE*(DDC2Info.SampleRate+DDC2Info.Bandwidth)/2/DDC2Info.SampleRate; //Set callback function for DDC2 streaming //Pointers to callback function which should not be called by the API have to be set to NULL. Callbacks.DDC2StreamCallback=MyDDC2StreamCallback; //Start DDC2 streaming for channel 0 //The SamplesPerBuffer parameter is set to FFT_SIZE which is size of the FFT to simplify //the example. StartDDC2(hDevice,0,2048); Code after... void MyDDC2StreamCallback(uint32_t Channel,const float *Buffer,uint32_t NumberOfSamples,uintptr_t UserData) { uint32_t i; //Compute FFT FFT(FFTBuffer,Buffer,FFT_SIZE); //Converts complex FFT result to dB for(i=0;i<FFT_SIZE;i++) { FFTBuffer[i]=(float)(10.0*log10(FFTBuffer[i*2]*FFTBuffer[i*2]+FFTBuffer[i*2+1]*FFTBuffer[i*2+1])); } //Apply compensation data to get amplitudes in frequency spectrum in dBm for(i=0;i<FFT_SIZE;i++) { FFTBuffer[i]+=Compensation[i]; } //now the FFTBuffer contains amplitudes in dBm //Useful band starts at the bin given by the FirstBin variable //and ends at the bin given by the LastBin variable. }
Determines compensation data for frequency spectrum of IF snapshots provided by the IFCallback and SweepingCallback callbacks.
C/C++ declaration
int GetIFSpectrumCompensation(int32_t hDevice,uint64_t FrontEndFrequency,float *Buffer,uint32_t Count);
Address retrieval
G39DDC_GET_IF_SPECTRUM_COMPENSATION GetIFSpectrumCompensation=(G39DDC_GET_IF_SPECTRUM_COMPENSATION)dlsym(API,"GetIFSpectrumCompensation");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.FrontEndFrequency[in] Specifies front-end frequency in Hz.Buffer[out] Pointer to a buffer to be filled with compensation data. This parameter cannot be NULL.Count[in] Specifies number of float items in the buffer pointed to by the Buffer parameter.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
The following example shows how to use the GetIFSpectrumCompensation function in IFCallback callback function:
//Let the following is prototype of a function which compute FFT from real signal stored in //the buffer pointed to be the Input parameter. Input samples are 16 bit, signed (from -32768 to +32767). Result is stored //in complex form in the buffer pointed to by the Output parameter. Size of the FFT is given be //the Size parameter. The example uses FFT with size 8192. void FFT(float *Output,const short *Input,int Size); #define FFT_SIZE 8192 //half of FFT size, we will use only the lower half of the FFT result with real input #define FFT_SIZE_2 (FFT_SIZE/2) //ADC sample rate - 100 MHz #define ADC_SAMPLE_RATE 100000000 int32_t hDevice; //handle to G39DDC device uint64_t FrontEndFrequency; //Front-end frequency float FFTBuffer[2*FFT_SIZE]; //Buffer for FFT result float Compensation[FFT_SIZE_2]; //Buffer for compensation data uint32_t FirstBin,LastBin; //the first and last bins in the FFT of useful IF band. G39DDC_CALLBACKS Callbacks; //Structure which contains pointer to callback functions G39DDC_DEVICE_INFO DeviceInfo; //Structure which contains device information to determine useful band in the IF snapshot Code before... //Retrieve device information GetDeviceInfo(hDevice,&DeviceInfo,sizeof(DeviceInfo)); //Retrieve front-end frequency GetFrontEndFrequency(hDevice,&FrontEndFrequency); //Retrieve compensation data. It is required the number of items to be equal to half of FFT size. GetIFSpectrumCompensation(hDevice,FrontEndFrequency,Compensation,FFT_SIZE_2); //Compensation data have to be updated after change of front-end frequency using SetFrontEndFrequency function. //In this case a mutual-exclusion synchronization method (for example critical section) should be used //if the Compensation buffer would be modified outside the MyDDC2StreamCallback callback. //Set callback function for IF snapshots //Pointers to callback function which should not be called by the API have to be set to NULL. Callbacks.IFCallback=MyIFCallback; SetCallbacks(hDevice,&Callbacks); //Start IF with snapshot period 50 ms StartIF(hDevice,50); Code after... void MyIFCallback(const int16_t *Buffer,uint32_t NumberOfSamples,uint32_t CenterFrequency,uint16_t Amplitude,uint32_t ADCSampleRate,uintptr_t UserData) { uint32_t i; uint32_t FirstBin,LastBin; //Compute FFT FFT(FFTBuffer,Buffer,FFT_SIZE); //Converts complex FFT result to dB, only for the lower half of the result, upper one is the same as lower but inverted for(i=0;i<FFT_SIZE_2;i++) { FFTBuffer[i]=(float)(10.0*log10(FFTBuffer[i*2]*FFTBuffer[i*2]+FFTBuffer[i*2+1]*FFTBuffer[i*2+1])); } //Apply compensation data to get amplitudes in frequency spectrum in dBm //We use only the lower half of the FFT result, because the upper one is the same but inverted for(i=0;i<FFT_SIZE_2;i++) { FFTBuffer[i]+=Compensation[i]; } //Calculate the first and last bins of the useful band in the FFT result //Center of the band is specified by the CenterFrequency parameter FirstBin=FFT_SIZE*(CenterFrequency-DeviceInfo.FrontEndWindowWidth/2)/ADC_SAMPLE_RATE; LastBin=FFT_SIZE*(CenterFrequency+DeviceInfo.FrontEndWindowWidth/2)/ADC_SAMPLE_RATE; //now the FFTBuffer contains amplitudes in dBm //Useful band starts at the bin given by the FirstBin variable //and ends at the bin given by the LastBin variable. }
Registers user-defined functions as callback functions called by the API.
C/C++ declaration
int SetCallbacks(int32_t hDevice,const G39DDC_CALLBACKS *Callbacks,uintptr_t UserData);
Address retrieval
G39DDC_SET_CALLBACKS SetCallbacks=(G39DDC_SET_CALLBACKS)dlsym(API,"SetCallbacks");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Callbacks[in] Pointer to a G39DDC_CALLBACKS structure which contains pointers to the user-defined function to be registered as callback functions.UserData[in] Specifies a user-defined value which is passed to callback functions.
Return value
If the function succeeds, the return value is non-zero.
If the function fails, the return value is zero, and errno is set appropriately.
Remarks
If the application does not require that the API calls some callback function, set related member of the G39DDC_CALLBACKS structure to NULL.
If value of the Callbacks parameter is NULL, all the callback functions are unregistered, the API will not call any callback function.
Flushes internal buffers and FIFOs in software and hardware parts. It marks specified buffers (filled by any samples) as empty. It can be useful in a scanning engine.
C/C++ declaration
int FlushBuffers(int32_t hDevice,uint32_t Channel,uint32_t Flags);
Address retrieval
G39DDC_FLUSH_BUFFERS FlushBuffers=(G39DDC_FLUSH_BUFFERS)dlsym(API,"FlushBuffers");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Channel[in] Specifies channel index. It can be 0, 1.Flags[in] Specifies which buffers should be flushed. The value can be combination of the following:
Value Meaning G39DDC_FLUSH_BUFFERS_IF Buffers which contains IF snapshots samples are flushed. In this case the Channel parameter is ignored. G39DDC_FLUSH_BUFFERS_DDC1 Buffers which contains samples from DDC1 output are flushed. G39DDC_FLUSH_BUFFERS_DDC2 Buffers which contains samples from DDC2 output are flushed. G39DDC_FLUSH_BUFFERS_AUDIO Buffers which contains samples from audio output are flushed.
Return value
If the method succeeds, the return value is non-zero.
If the method fails, the return value is zero, and errno is set appropriately.
Remarks
The function is synchronous. When it is finished, specifies buffers are already flushed.
Retrieves current internal temperature of the G39DDC device.
C/C++ declaration
int GetTemperature(int32_t hDevice,uint32_t *Temperature);
Address retrieval
G39DDC_GET_TEMPERATURE GetTemperature=(G39DDC_GET_TEMPERATURE)dlsym(API,"GetTemperature");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.Temperature[out] Pointer to a variable that receives current internal temperature in degrees of Celsius. This parameter cannot be NULL.
Return value
If the method succeeds, the return value is non-zero.
If the method fails, the return value is zero, and errno is set appropriately.
Remarks
The G39DDC device has to be turned on using the SetPower function before GetTemperature is used. Otherwise GetTemperature fails.
Retrieves current error state of the G39DDC device.
C/C++ declaration
int GetDeviceState(int32_t hDevice,uint32_t *State);
Address retrieval
G39DDC_GET_DEVICE_STATE GetDeviceState=(G39DDC_GET_DEVICE_STATE)dlsym(API,"GetDeviceState");
Parameters
hDevice[in] Handle to G39DDC device returned by the OpenDevice function.State[out] Pointer to a variable that receives current error state of the device. This parameter cannot be NULL.It is combination of the following values:
Value Meaning G39DDC_DEVICE_STATE_TEMP_ERROR Critical temperature detected. Device is turned off. G39DDC_DEVICE_STATE_FAN_ERROR Built-in fan error detected. The fun is not operational. G39DDC_DEVICE_STATE_VCC_ERROR Voltage error detected. G39DDC_DEVICE_STATE_COMM_ERROR Internal hardware communication error detected. G39DDC_DEVICE_STATE_SUSPENDED Operating system was suspended. Device is turned off.
Return value
If the method succeeds, the return value is non-zero.
If the method fails, the return value is zero, and errno is set appropriately.
Contains information about G39DDC device.
C/C++ declaration
#pragma pack(push,1) typedef struct { char DevicePath[64]; uint8_t InterfaceType; char SerialNumber[9]; uint16_t HWVersion; uint16_t FWVersion; uin8_t EEPROMVersion; uint32_t ChannelCount; uint64_t FrontEndMinFrequency; uint64_t FrontEndMaxFrequency; uint64_t FrontEndMaxHFFrequency; uint32_t FrontEndFrequencyStep; uint32_t FrontEndWindowWidth; uint32_t HardwareOptions; } G39DDC_DEVICE_INFO; #pragma pack(pop)
Members
DevicePathDevice system path in a null-terminated string. It is used to open the device using object interface.InterfaceTypeDevice interface type. The value can be one of the following:
G39DDC_INTERFACE_TYPE_PCIE
The device is connected to the computer via PCI express.G39DDC_INTERFACE_TYPE_USB
The device is connected to the computer via USB.SerialNumberSerial number in null-terminated string.HWVersionVersion of the hardware.FWVersionVersion of the firmware.EEPROMVersionEEPROM structure version.ChannelCountNumber of channels. It is equal to 2.FrontEndMinFrequencyMinimum front-end frequency (in Hz) which can be used in the SetFrontEndFrequency and StartSweeping functions.FrontEndMaxFrequencyMaximum front-end frequency (in Hz) which can be used in the SetFrontEndFrequency and StartSweeping functions.FrontEndMaxHFFrequencyMaximum front-end frequency (in Hz) when the front-end is in HF mode.FrontEndFrequencyStepTuning step (in Hz) of the front-end. The frequencies used in the SetFrontEndFrequency and StartSweeping functions have to be multiple of this value. The only exception is if the frequency is equal to FrontEndMinFrequency which need not be multiple if this value.FrontEndWindowWidthUseful bandwidth (in Hz) in IF snapshots passed to the IFCallback and SweepingCallback callbacks. Center of the bandwidth is specified by the CenterFrequency parameter of these callbacks.HardwareOptionsHardware options. It can be combination of the following values:
Value Meaning G39DDC_HARDWARE_OPTIONS_EXTERNAL_REFERENCE The device supports external reference. G39DDC_HARDWARE_OPTIONS_AUDIO_OUTPUT The device has audio output connector. G39DDC_HARDWARE_OPTIONS_FCC FCC receiver. The receiver does not allow to be tuned to prohibited frequency bands.
Contains information about DDC type.
C/C++ declaration
#pragma pack(push,1) typedef struct { uint32_t SampleRate; uint32_t Bandwidth; uint32_t BitsPerSample; } G39DDC_DDC_INFO; #pragma pack(pop)
Members
SampleRateSample rate of I/Q signal in Hz.BandwidthUseful bandwidth in Hz.BitsPerSampleNumber of bits per sample. It can be 16 or 32. It is used to determine bits per sample for DDC1.
Contains information about DDC type.
C/C++ declaration
#pragma pack(push,1) typedef struct { uint32_t Tune; uint32_t Lock; } G39DDC_AMS_CAPTURE_RANGE; #pragma pack(pop)
Members
TuneInitial capture range in Hz.LockCapture range (in Hz) used when AMS demodulator is locked.
Contains pointers to user-defined functions to be registered as callback functions.
Each callback function is called in context of thread created by the API. If some shared data are accessed inside callback functions, it is recommended to use a mutual-exclusion synchronization method. The application should not call any G39DDC API function from inside callback functions, otherwise it can cause deadlock or the application can become to unpredictable state.
C/C++ declaration
#pragma pack(push,1) typedef struct { G39DDC_IF_CALLBACK IFCallback; G39DDC_DDC1_STREAM_CALLBACK DDC1StreamCallback; G39DDC_DDC1_PLAYBACK_STREAM_CALLBACK DDC1PlaybackStreamCallback; G39DDC_DDC2_STREAM_CALLBACK DDC2StreamCallback; G39DDC_DDC2_PREPROCESSED_STREAM_CALLBACK DDC2PreprocessedStreamCallback; G39DDC_AUDIO_STREAM_CALLBACK AudioStreamCallback; G39DDC_AUDIO_PLAYBACK_STREAM_CALLBACK AudioPlaybackStreamCallback; G39DDC_SWEEPING_CALLBACK SweepingCallback; } G39DDC_CALLBACKS; #pragma pack(pop)
Members
Pointer to a user-defined function to be registered as IF callback. It is called by the API to pass IF snapshots to the application. Sending of IF snapshots is started using the StartIF function.
C/C++ declaration
void IFCallback(const int16_t *Buffer,uint32_t NumberOfSamples,uint32_t CenterFrequency,uint16_t Amplitude,uint32_t ADCSampleRate,uintptr_t UserData);Parameters
BufferPointer to the buffer which contains samples directly received from ADC. Sample rate is 100 MHz, sample is 16 bit signed little endian (values are from range -32768 to +32767).NumberOfSamplesSpecifies number of samples in the buffer pointed to be the Buffer parameter. This is usually 65536.CenterFrequencySpecifies center frequency of the useful band in received 50 MHz wide snapshot. Not whole 50 MHz band of the snapshot is usable. Usable bandwidth is specified by the FrontEndWindowWidth member of the G39DDC_DEVICE_INFO structure.AmplitudeSpecifies maximum amplitude at ADC output. Measurement of the maximum is started at the end of the previous snapshot to the current one. The possible value is 0 to 32767.ADCSampleRateSpecifies sample rate of the ADC in Hz. It can be a bit different from 100 MHz.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Pointer to a user-defined function to be registered as DDC1 stream callback. It is called by the API to pass I/Q samples from DDC1 to the application. The DDC1 streaming can be started using the StartDDC1 or StartDDC1Playback function.
C/C++ declaration
void DDC1StreamCallback(uint32_t Channel,const void *Buffer,uint32_t NumberOfSamples,uint32_t BitsPerSample,uintptr_t UserData);Parameters
ChannelSpecifies channel index. It can be 0, 1.BufferPointer to the buffer which contains I/Q sample sets from DDC1. Sample rate and bits per sample is given by used DDC type, see the SetDDC1 function. One I/Q sample set consists of two samples.NumberOfSamplesSpecifies number of I/Q sample sets in the buffer pointed to by the Buffer parameter. This value is equal to value of the SamplesPerBuffer parameter of the StartDDC1 or StartDDC1Playback function.BitsPerSampleSpecifies number of bits per sample. It is given by DDC type used for DDC1 and it can be 16 or 32. If it is 16, sample is 16 bit integer (32bits per I/Q sample set), signed, little endian, from range -32768 to +32767. If it is 32, sample is 32bit integer (64bits per I/Q sample set), signed, little endian, from range -2147483648 to +2147483647.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Pointer to a user-defined function to be registered as DDC1 playback stream callback. It is called by the API to fill the buffer with I/Q samples by the applcation. The DDC1 playback can be started using the StartDDC1Playback function.
C/C++ declaration
int DDC1PlaybackStreamCallback(uint32_t Channel,void *Buffer,uint32_t NumberOfSamples,uint32_t BitsPerSample,uintptr_t UserData);Parameters
ChannelSpecifies channel index. It can be 0, 1.BufferPointer to the buffer to be filled with I/Q sample sets. Sample rate and bits per sample is given by used DDC type, see the SetDDC1 function.NumberOfSamplesSpecifies number of I/Q sample sets to be stored to the buffer pointed to by the Buffer parameter. This value is equal to value of the SamplesPerBuffer parameter of the StartDDC1Playback function. If the application does not have requested number of sample sets, it has to fill the buffer with zeros. One I/Q sample set consists of two samples.BitsPerSampleSpecifies number of bits per sample. It is given by DDC type used for DDC1 and it can be 16 or 32. If it is 16, sample is 16 bit integer (32bits per I/Q sample set), signed, little endian, from range -32768 to +32767. If it is 32, sample is 32bit integer (64bits per I/Q sample set), signed, little endian, from range -2147483648 to +2147483647.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Return value
The application should return non-zero to continue playback. The application should return zero to stop the API to call DDC1PlaybackStreamCallback again. This does not stop DDC1 playback, it has to be done explicitly by the application calling the StopDDC1 function from the thread in which the device was open using the OpenDevice function. StopDDC1 must not be called from inside the callback function.Pointer to a user-defined function to be registered as DDC2 stream callback. It is called by the API to pass I/Q samples from DDC2 to the application. The DDC2 streaming can be started using the StartDDC2 function.
C/C++ declaration
void DDC2StreamCallback(uint32_t Channel,const float *Buffer,uint32_t NumberOfSamples,uintptr_t UserData);Parameters
ChannelSpecifies channel index. It can be 0, 1.BufferPointer to the buffer which contains I/Q sample sets from DDC2. Sample rate is given by the DDC type of the DDC2. Use the GetDDC2 function to determine current DDC type of the DDC2. Sample is 32bit IEEE float from range -1.0 to 1.0. One I/Q sample set consists of two samples.NumberOfSamplesSpecifies number of I/Q sample sets in the buffer pointed to by the Buffer parameter. This value is equal to value of the SamplesPerBuffer parameter of the StartDDC2 function.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Pointer to a user-defined function to be registered as preprocessed DDC2 stream callback. It is called by the API to pass preprocessed I/Q samples from DDC2 to the application. The samples are filtered by the demodulator filter, notch filter and affected by AGC or fixed gain. The DDC2 streaming can be started using the StartDDC2 function.
C/C++ declaration
void DDC2PreprocessedStreamCallback(uint32_t Channel,const float *Buffer,uint32_t NumberOfSamples, float SlevelPeak,float SlevelRMS,uintptr_t UserData);Parameters
ChannelSpecifies channel index. It can be 0, 1.BufferPointer to the buffer which contains preprocessed I/Q sample sets from DDC2. Sample rate is given by the DDC type of the DDC2. Use the GetDDC2 function to determine current DDC type of the DDC2. Sample is 32bit IEEE float from range -1.0 to 1.0. One I/Q sample set consists of two samples.NumberOfSamplesSpecifies number of I/Q sample sets in the buffer pointed to by the Buffer parameter. This value is equal to value of the SamplesPerBuffer parameter of the StartDDC2 function.SlevelPeakSpecifies peak signal level in Volts evaluated from samples stored in the buffer pointed to by the Buffer parameter.SlevelRMSSpecifies RMS signal level in Volts evaluated from samples stored in the buffer pointed to by the Buffer parameter. For detailed information how to convert RMS signal level to dBm, see remarks of the GetSignalLevel function.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Pointer to a user-defined function to be registered as audio stream callback. It is called by the API to pass audio samples to the application. The audio streaming can be started using the StartAudio or StartAudioPlayback function. The callback is invoked three times for each audio buffer (see description of the Type parameter).
C/C++ declaration
void AudioStreamCallback(uint32_t Channel,uint32_t Type,const float *Buffer,uint32_t NumberOfSamples,uintptr_t UserData);Parameters
ChannelSpecifies channel index. It can be 0, 1.TypeSpecifies type (stage) of audio samples stored in the buffer pointed to by the Buffer parameter. Value of this parameter can be one of the following:
Value Meaning 0 The buffer contains audio samples affected by audio gain (see SetAudioGain). 1 The buffer contains audio samples affected by audio gain and audio filter (see SetAudioGain and SetAudioFilter). 2 The buffer contains audio samples affected by audio gain, audio filter and volume (see SetAudioGain, SetAudioFilter, SetVolume and SetMute). BufferPointer to the buffer which contains samples of audio signal. The signal consists of two channels (interleaved), sample rate is specified by the SetAudio function, sample is 32bit IEEE float from range -1.0 to 1.0.NumberOfSamplesSpecifies number of samples to be stored in the buffers pointed to by the Buffer parameter. This value is equal to value of the SamplesPerBuffer parameter of the StartAudio or StartAudioPlayback function.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Pointer to a user-defined function to be registered as audio playback stream callback. It is called by the API to fill the buffer with audio samples by the application. The audio playback can be started using the StartAudioPlayback function.
C/C++ declaration
int AudioPlaybackStreamCallback(uint32_t Channel,float *Buffer,uint32_t NumberOfSamples,uinptr_t UserData);Parameters
ChannelSpecifies channel index. It can be 0, 1.BufferPointer to the buffer to by filled with audio samples. The audio signal is two channel, sample rate is specified by the SetAudio function, sample is 32bit IEEE float from range -1.0 to 1.0.NumberOfSamplesSpecifies number of samples in the buffer pointed to by the Buffer parameter. This value is equal to value of the SamplesPerBuffer parameter of the StartAudioPlayback function. If the application does not have requested number of samples, the application has to fill the buffer with zeros.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Return value
The application should return non-zero to continue playback. The application should return zero to stop the API to call AudioPlaybackStreamCallback again. This does not stop audio playback, it has to be done explicitly by the application calling the StopAudio function from the thread in which the device was open using the OpenDevice function. StopAudio must not be called from inside the callback function.Pointer to a user-defined function to be registered as sweeping callback. It is called by the API to pass IF snapshots to the application during sweeping. Sending of them is started using the StartSweeping or StartSweepingEx function.
C/C++ declaration
int SweepingCallback(const int16_t *Buffer,uint32_t NumberOfSamples,uint32_t CenterFrequency,uint64_t Frequency,uintptr_t UserData);Parameters
BufferPointer to the buffer which contains samples directly received from ADC. Sample rate is 100 MHz, sample is 16 bit signed little endian (values are from range -32768 to +32767).NumberOfSamplesSpecifies number of samples in the buffer pointed to be the Buffer parameter. If the sweeping is started using the StartSweeping function, the NumberOfSamples is equal to 65536. If the sweeping is started using the StartSweeppingEx function and its LargeIfBuffer parameter is zero, the NumberOfSamples is equal to 65536. If the sweeping is started using the StartSweeppingEx function and its LargeIfBuffer parameter is non-zero, the NumberOfSamples is equal to 262144.CenterFrequencySpecifies center frequency of the useful band in received 50 MHz wide snapshot. Not whole 50 MHz band of the snapshot is usable. Usable bandwidth is specified by the FrontEndWindowWidth member of the G39DDC_DEVICE_INFO structure.FrequencyFront-end frequency (in Hz) when the snapshot was made.UserDataUser-defined data. It is value passed to the SetCallbacks function as the UserData parameter.Return value
The application should return non-zero to continue sweeping. The application should return zero to stop API to call SweepingCallback again. This does not stop the sweeping, it has to be done explicitly by the application calling the StopSweeping function from the thread in which the device was open using the OpenDevice function. StopSweeping must not be called from inside the callback function.