Merge pull request #192 from pennam/pdm_gain

Align usage of PDM.setGain()

Author: facchinm

libraries/PDM/src/PDM.h

@@ -30,14 +30,16 @@ class PDMClass
   PDMClass(int dinPin, int clkPin, int pwrPin);
   virtual ~PDMClass();
 
-  int begin(int channels, long sampleRate);
+  int begin(int channels, int sampleRate);
   void end();
 
   virtual int available();
   virtual int read(void* buffer, size_t size);
 
   void onReceive(void(*)(void));
 
+  //PORTENTA_H7 min -12 max 51
+  //NANO 33 BLE SENSe min 0 max 80
   void setGain(int gain);
   void setBufferSize(int bufferSize);
 
@@ -50,7 +52,11 @@ class PDMClass
   int _pwrPin;
 
   int _channels;
-  
+  int _samplerate;
+
+  int _gain;
+  int _init;
+
   PDMDoubleBuffer _doubleBuffer;
 
   void (*_onReceive)(void);

libraries/PDM/src/nrf52/PDM.cpp

@@ -39,17 +39,22 @@ PDMClass::PDMClass(int dinPin, int clkPin, int pwrPin) :
   _dinPin(dinPin),
   _clkPin(clkPin),
   _pwrPin(pwrPin),
-  _onReceive(NULL)
+  _onReceive(NULL),
+  _gain(-1),
+  _channels(-1),
+  _samplerate(-1),
+  _init(-1)
 {
 }
 
 PDMClass::~PDMClass()
 {
 }
 
-int PDMClass::begin(int channels, long sampleRate)
+int PDMClass::begin(int channels, int sampleRate)
 {
   _channels = channels;
+  _samplerate = sampleRate;
 
   // Enable high frequency oscillator if not already enabled
   if (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0) {
@@ -83,7 +88,10 @@ int PDMClass::begin(int channels, long sampleRate)
       return 0; // unsupported
   }
 
-  setGain(DEFAULT_PDM_GAIN);  
+  if(_gain == -1) {
+    _gain = DEFAULT_PDM_GAIN;
+  }
+  nrf_pdm_gain_set(_gain, _gain);
 
   // configure the I/O and mux
   pinMode(_clkPin, OUTPUT);
@@ -175,7 +183,8 @@ void PDMClass::onReceive(void(*function)(void))
 
 void PDMClass::setGain(int gain)
 {
-  nrf_pdm_gain_set(gain, gain);
+  _gain = gain;
+  nrf_pdm_gain_set(_gain, _gain);
 }
 
 void PDMClass::setBufferSize(int bufferSize)

libraries/PDM/src/rp2040/OpenPDMFilter.c

@@ -193,7 +193,7 @@ void Open_PDM_Filter_Init(TPDMFilter_InitStruct *Param)
   }
 
   sub_const = sum >> 1;
-  div_const = sub_const * Param->MaxVolume / 32768 / filterGain;
+  div_const = sub_const * Param->MaxVolume / 32768 / Param->filterGain;
   div_const = (div_const == 0 ? 1 : div_const);
 
 #ifdef USE_LUT

libraries/PDM/src/rp2040/OpenPDMFilter.h

@@ -54,10 +54,6 @@
 #define SINCN            3
 #define DECIMATION_MAX 128
 
-//#define FILTER_GAIN     16
-extern uint16_t filterGain;
-
-
 #define HTONS(A) ((((uint16_t)(A) & 0xff00) >> 8) | \
                  (((uint16_t)(A) & 0x00ff) << 8))
 #define RoundDiv(a, b)    (((a)>0)?(((a)+(b)/2)/(b)):(((a)-(b)/2)/(b)))
@@ -84,6 +80,7 @@ typedef struct {
   uint16_t HP_ALFA;
   uint16_t bit[5];
   uint16_t byte;
+  uint16_t filterGain;
 } TPDMFilter_InitStruct;
 
 

libraries/PDM/src/rp2040/PDM.cpp

@@ -32,8 +32,6 @@ int16_t* volatile finalBuffer;
 // OpenPDM filter used to convert PDM into PCM
 #define FILTER_GAIN     16
 TPDMFilter_InitStruct filter;
-uint16_t filterGain = FILTER_GAIN;
-
 
 extern "C" {
   __attribute__((__used__)) void dmaHandler(void)
@@ -47,15 +45,19 @@ PDMClass::PDMClass(int dinPin, int clkPin, int pwrPin) :
   _dinPin(dinPin),
   _clkPin(clkPin),
   _pwrPin(pwrPin),
-  _onReceive(NULL)
+  _onReceive(NULL),
+  _gain(-1),
+  _channels(-1),
+  _samplerate(-1),
+  _init(-1)
 {
 }
 
 PDMClass::~PDMClass()
 {
 }
 
-int PDMClass::begin(int channels, long sampleRate)
+int PDMClass::begin(int channels, int sampleRate)
 {
   //_channels = channels; // only one channel available
 
@@ -71,15 +73,19 @@ int PDMClass::begin(int channels, long sampleRate)
     rawBufferLength = finalBufferLength;
   }
 
-	/* Initialize Open PDM library */
-	filter.Fs = sampleRate;
-	filter.nSamples = rawBufferLength; 
-	filter.LP_HZ = sampleRate/2;
-	filter.HP_HZ = 10;
-	filter.In_MicChannels = 1;
-	filter.Out_MicChannels = 1;
-	filter.Decimation = decimation;
-	Open_PDM_Filter_Init(&filter);
+  /* Initialize Open PDM library */
+  filter.Fs = sampleRate;
+  filter.nSamples = rawBufferLength;
+  filter.LP_HZ = sampleRate/2;
+  filter.HP_HZ = 10;
+  filter.In_MicChannels = 1;
+  filter.Out_MicChannels = 1;
+  filter.Decimation = decimation;
+  if(_gain == -1) {
+    _gain = FILTER_GAIN;
+  }
+  filter.filterGain = _gain;
+  Open_PDM_Filter_Init(&filter);
 
   // Configure PIO state machine
   float clkDiv = (float)clock_get_hz(clk_sys) / sampleRate / decimation / 2; 
@@ -110,6 +116,8 @@ int PDMClass::begin(int channels, long sampleRate)
     true                // Start immediately
   );
 
+  _init = 1;
+
   return 1;
 }
 
@@ -142,7 +150,11 @@ void PDMClass::onReceive(void(*function)(void))
 
 void PDMClass::setGain(int gain)
 {
-  filterGain = gain;
+  _gain = gain;
+  if(_init == 1) {
+    filter.filterGain = _gain;
+    Open_PDM_Filter_Init(&filter);
+  }
 }
 
 void PDMClass::setBufferSize(int bufferSize)
@@ -185,4 +197,4 @@ void PDMClass::IrqHandler(bool halftranfer)
 
 PDMClass PDM(PIN_PDM_DIN, PIN_PDM_CLK, -1);
 
-#endif
+#endif

libraries/PDM/src/stm32/PDM.cpp

@@ -34,18 +34,19 @@ PDMClass::PDMClass(int dinPin, int clkPin, int pwrPin) :
   _dinPin(dinPin),
   _clkPin(clkPin),
   _pwrPin(pwrPin),
-  _onReceive(NULL)
+  _onReceive(NULL),
+  _gain(-1),
+  _channels(-1),
+  _samplerate(-1),
+  _init(-1)
 {
 }
 
 PDMClass::~PDMClass()
 {
 }
 
-static int gain_db = -1;
-static int _samplerate = -1;
-
-int PDMClass::begin(int channels, long sampleRate) {
+int PDMClass::begin(int channels, int sampleRate) {
 
   if (isBoardRev2()) {
     mbed::I2C i2c(PB_7, PB_6);
@@ -65,14 +66,13 @@ int PDMClass::begin(int channels, long sampleRate) {
   _channels = channels;
   _samplerate = sampleRate;
 
-  if (gain_db == -1) {
-    gain_db = 24;
+  if (_gain == -1) {
+    _gain = 24;
   }
 
-  //g_pcmbuf = (uint16_t*)_doubleBuffer.data();
-
-  if(py_audio_init(channels, sampleRate, gain_db, 0.9883f)) {
+  if(py_audio_init(channels, sampleRate, _gain, 0.9883f)) {
     py_audio_start_streaming();
+    _init = 1;
     return 1;
   }
   return 0;
@@ -103,9 +103,10 @@ void PDMClass::onReceive(void(*function)(void))
 
 void PDMClass::setGain(int gain)
 {
-  gain_db = gain;
-  //end();
-  //begin(_channels, _samplerate);
+  _gain = gain;
+  if(_init == 1) {
+    py_audio_gain_set(gain);
+  }
 }
 
 void PDMClass::setBufferSize(int bufferSize)

libraries/PDM/src/stm32/audio.c

@@ -309,6 +309,18 @@ int py_audio_init(size_t channels, uint32_t frequency, int gain_db, float highpa
     return 1;
 }
 
+void py_audio_gain_set(int gain_db)
+{
+    // Configure PDM filters
+    for (int i=0; i<g_i_channels; i++) {
+        PDM_FilterConfig[i].mic_gain = gain_db;
+        //This will be called only after init so PDM_FilterConfig structure is already filled
+        //PDM_FilterConfig[i].output_samples_number = samples_per_channel;
+        //PDM_FilterConfig[i].decimation_factor = decimation_factor_const;
+        PDM_Filter_setConfig(&PDM_FilterHandler[i], &PDM_FilterConfig[i]);
+    }
+}
+
 void py_audio_deinit()
 {
     // Stop SAI DMA.

libraries/PDM/src/stm32/audio.h

@@ -32,6 +32,7 @@
 
 void py_audio_deinit();
 int py_audio_init(size_t g_channels, uint32_t frequency, int gain_db, float highpass);
+void py_audio_gain_set(int gain_db);
 void audio_pendsv_callback(void);
 void py_audio_start_streaming();
 void py_audio_stop_streaming();