Fix incorrect ADC channel counting with 16,17. Also make averaging toggleable.

This bug caused wrong measurements, DAC distortion and instability with 16+17
and at least 1 other channel.

units/adc/_adc_core.c

@@ -327,8 +327,7 @@ void UADC_DMA_Handler(void *arg)
  */
 void UADC_ADC_EOS_Handler(void *arg)
 {
-    GPIOC->BSRR = 0x01;//TODO remove
+//    GPIOC->BSRR = 0x01;
-
     Unit *unit = arg;
     struct priv *priv = unit->data;
 
@@ -341,11 +340,16 @@ void UADC_ADC_EOS_Handler(void *arg)
         goto exit;
     }
 
+//    GPIOC->BSRR = 0x02;
     // Wait for the DMA to complete copying the last sample
     uint32_t dmapos = DMA_POS(priv);
-    if ((DMA_POS(priv) % priv->nb_channels) != 0) {
+    uint32_t err = (dmapos % priv->nb_channels);
-        hw_wait_while((dmapos = DMA_POS(priv)) % priv->nb_channels != 0, 100); // XXX this could be changed to reading it from the DR instead
+    if (err != 0) {
+        GPIOC->BSRR = 0x02;
+        hw_wait_while(((dmapos = DMA_POS(priv)) % priv->nb_channels) != 0, 10);
+        GPIOC->BRR = 0x02;
     }
+//    GPIOC->BRR = 0x02;
 
     uint32_t sample_pos;
     if (dmapos == 0) {
@@ -355,14 +359,22 @@ void UADC_ADC_EOS_Handler(void *arg)
     }
     sample_pos -= priv->nb_channels;
 
-    int cnt = 0; // index of the sample within the group
+    uint8_t cnt = 0; // index of the sample within the group
 
-    const bool can_average = priv->real_frequency_int < UADC_MAX_FREQ_FOR_AVERAGING;
+    const bool can_average = priv->cfg.enable_averaging && priv->real_frequency_int < UADC_MAX_FREQ_FOR_AVERAGING;
     const uint32_t channels_mask = priv->channels_mask;
 
+    uint16_t val;
+    // TODO change this to a pre-computed byte array traversal
+
     for (uint8_t i = 0; i < 18; i++) {
         if (channels_mask & (1 << i)) {
-            const uint16_t val = priv->dma_buffer[sample_pos+cnt];
+//            if (cnt == priv->nb_channels-1) {
+//                val = last_sample; // DMA may not have finished copying it yet
+//            } else {
+                val = priv->dma_buffer[sample_pos+cnt];
+//            }
+
             cnt++;
 
             if (can_average) {
@@ -375,8 +387,9 @@ void UADC_ADC_EOS_Handler(void *arg)
         }
     }
 
+    // Triggering condition test
     if (priv->opmode == ADC_OPMODE_ARMED) {
-        const uint16_t val =  priv->last_samples[priv->trigger_source];
+        val =  priv->last_samples[priv->trigger_source];
 
         if ((priv->trig_prev_level < priv->trig_level) && val >= priv->trig_level && (bool) (priv->trig_edge & 0b01)) {
             // Rising edge
@@ -401,7 +414,7 @@ void UADC_ADC_EOS_Handler(void *arg)
     }
 
 exit:
-    GPIOC->BRR = 0x01;//TODO remove
+//    GPIOC->BRR = 0x01;
     return;
 }
 

units/adc/_adc_init.c

@@ -21,6 +21,7 @@ error_t UADC_preInit(Unit *unit)
     priv->cfg.frequency = 1000;
     priv->cfg.buffer_size = 256; // in half-words
     priv->cfg.averaging_factor = 500; // 0.5
+    priv->cfg.enable_averaging = true;
 
     priv->opmode = ADC_OPMODE_UNINIT;
 
@@ -120,9 +121,10 @@ error_t UADC_init(Unit *unit)
         // Claim and configure all analog pins
         priv->nb_channels = 0;
         for (uint8_t i = 0; i <= UADC_MAX_CHANNEL; i++) {
-            if (priv->cfg.channels & (1 << i)) {
+            if (priv->cfg.channels & (1UL << i)) {
                 priv->nb_channels++;
 
+                do {
                     char c;
                     uint8_t num;
                     if (i <= 7) {
@@ -136,7 +138,8 @@ error_t UADC_init(Unit *unit)
                     else if (i <= 15) {
                         c = 'C';
                         num = (uint8_t) (i - 10);
-                } else {
+                    }
+                    else {
                         break;
                     }
 
@@ -147,6 +150,7 @@ error_t UADC_init(Unit *unit)
 
                     LL_GPIO_SetPinPull(port, ll_pin, LL_GPIO_PULL_NO);
                     LL_GPIO_SetPinMode(port, ll_pin, LL_GPIO_MODE_ANALOG);
+                } while (0);
             }
         }
 

units/adc/_adc_internal.h

@@ -46,6 +46,7 @@ struct priv {
         uint32_t frequency;   //!< Timer frequency in Hz. Note: not all frequencies can be achieved accurately
         uint32_t buffer_size; //!< Buffer size in bytes (count 2 bytes per channel per measurement) - faster sampling freq needs bigger buffer
         uint16_t averaging_factor;  //!< Exponential averaging factor 0-1000
+        bool enable_averaging;
     } cfg;
 
     // Peripherals

units/adc/_adc_settings.c

@@ -23,6 +23,10 @@ void UADC_loadBinary(Unit *unit, PayloadParser *pp)
     priv->cfg.frequency = pp_u32(pp);
     priv->cfg.buffer_size = pp_u32(pp);
     priv->cfg.averaging_factor = pp_u16(pp);
+
+    if (version >= 1) {
+        priv->cfg.enable_averaging = pp_bool(pp);
+    }
 }
 
 /** Write to a binary buffer for storing in Flash */
@@ -30,13 +34,14 @@ void UADC_writeBinary(Unit *unit, PayloadBuilder *pb)
 {
     struct priv *priv = unit->data;
 
-    pb_u8(pb, 0); // version
+    pb_u8(pb, 1); // version
 
     pb_u32(pb, priv->cfg.channels);
     pb_u8(pb, priv->cfg.sample_time);
     pb_u32(pb, priv->cfg.frequency);
     pb_u32(pb, priv->cfg.buffer_size);
     pb_u16(pb, priv->cfg.averaging_factor);
+    pb_bool(pb, priv->cfg.enable_averaging);
 }
 
 // ------------------------------------------------------------------------
@@ -64,6 +69,9 @@ error_t UADC_loadIni(Unit *unit, const char *key, const char *value)
         priv->cfg.averaging_factor = cfg_u16_parse(value, &suc);
         if (priv->cfg.averaging_factor > 1000) return E_BAD_VALUE;
     }
+    else if (streq(key, "averaging")) {
+        priv->cfg.enable_averaging = cfg_bool_parse(value, &suc);
+    }
     else {
         return E_BAD_KEY;
     }
@@ -98,6 +106,9 @@ void UADC_writeIni(Unit *unit, IniWriter *iw)
     iw_entry_d(iw, "buffer_size", priv->cfg.buffer_size);
 
     iw_cmt_newline(iw);
+    iw_comment(iw, "Enable continuous sampling with averaging");
+    iw_comment(iw, "Caution: This can cause DAC output glitches");
+    iw_entry_s(iw, "averaging", str_yn(priv->cfg.enable_averaging));
     iw_comment(iw, "Exponential averaging coefficient (permil, range 0-1000 ~ 0.000-1.000)");
     iw_comment(iw, "- used formula: y[t]=(1-k)*y[t-1]+k*u[t]");
     iw_comment(iw, "- not available when a capture is running");

units/adc/unit_adc.c

@@ -191,8 +191,13 @@ static error_t UADC_handleRequest(Unit *unit, TF_ID frame_id, uint8_t command, P
                 return E_BUSY;
             }
 
+            if (! priv->cfg.enable_averaging) {
+                com_respond_str(MSG_ERROR, frame_id, "Averaging disabled");
+                return E_FAILURE;
+            }
+
             if (priv->real_frequency_int > UADC_MAX_FREQ_FOR_AVERAGING) {
-                com_respond_str(MSG_ERROR, frame_id, "Too fast for smoothing");
+                com_respond_str(MSG_ERROR, frame_id, "Too fast for averaging");
                 return E_FAILURE;
             }