fixed sample rate setting

4 files changed, 52 insertions, 55 deletions

diff --git a/source/adc.cpp b/source/adc.cpp
index a8c0e62..c8da25f 100644
--- a/source/adc.cpp
+++ b/source/adc.cpp
@@ -38,36 +38,23 @@ static ADCConversionGroup adc_group_config = {
 };
 
 constexpr static const GPTConfig gpt_config = {
-    .frequency = 14400000,
+    .frequency = 36000000,
     .callback = nullptr,
     .cr2 = TIM_CR2_MMS_1, /* TRGO */
     .dier = 0
 };
 
+#define ADC_CCR_PRESC_DIV1 (0)
+#define ADC_SAMPLE_RATE_SETTINGS_COUNT (7)
 static uint32_t adc_sample_rate_settings[] = {
-    10, ADC_SMPR_SMP_47P5, 4608, // 3125
-    11, ADC_SMPR_SMP_12P5, 3840, // 3750
-    9,  ADC_SMPR_SMP_47P5, 2304, // 6250
-    10, ADC_SMPR_SMP_12P5, 1920, // 7500
-    8,  ADC_SMPR_SMP_47P5, 1152, // 12K5
-    9,  ADC_SMPR_SMP_12P5, 960,  // 15K
-    7,  ADC_SMPR_SMP_47P5, 576,  // 25K
-    8,  ADC_SMPR_SMP_12P5, 480,  // 30K
-    5,  ADC_SMPR_SMP_47P5, 360,  // 40K
-    4,  ADC_SMPR_SMP_47P5, 288,  // 50K
-    7,  ADC_SMPR_SMP_12P5, 240,  // 60K
-    6,  ADC_SMPR_SMP_12P5, 180,  // 80K
-    5,  ADC_SMPR_SMP_12P5, 150,  // 96K
-    2,  ADC_SMPR_SMP_47P5, 144,  // 100K
-    4,  ADC_SMPR_SMP_12P5, 120,  // 120K
-    3,  ADC_SMPR_SMP_12P5, 90,   // 160K
-    1,  ADC_SMPR_SMP_47P5, 72,   // 200K
-    2,  ADC_SMPR_SMP_12P5, 60,   // 240K
-    0,  ADC_SMPR_SMP_47P5, 36,   // 400K
-    1,  ADC_SMPR_SMP_12P5, 30,   // 480K
-    1,  ADC_SMPR_SMP_2P5,  18,   // 800K
-    0,  ADC_SMPR_SMP_12P5, 15,   // 960K
-    0,  ADC_SMPR_SMP_2P5,  9     // 1M6
+    // Rate    PLLSAI2N  ADC_PRESC            ADC_SMPR           GPT_DIV
+    /* 16k  */ 8,        ADC_CCR_PRESC_DIV10, ADC_SMPR_SMP_12P5, 2250,
+    /* 48k  */ 24,       ADC_CCR_PRESC_DIV10, ADC_SMPR_SMP_12P5, 750,
+    /* 96k  */ 48,       ADC_CCR_PRESC_DIV10, ADC_SMPR_SMP_12P5, 375,
+    /* 100k */ 40,       ADC_CCR_PRESC_DIV8,  ADC_SMPR_SMP_12P5, 360,
+    /* 400k */ 40,       ADC_CCR_PRESC_DIV2,  ADC_SMPR_SMP_12P5, 90,
+    /* 1M   */ 38,       ADC_CCR_PRESC_DIV1,  ADC_SMPR_SMP_6P5,  36,
+    /* 2M   */ 76,       ADC_CCR_PRESC_DIV1,  ADC_SMPR_SMP_6P5,  18
 };
 
 static bool adc_is_read_finished = false;
@@ -92,17 +79,35 @@ namespace adc
     void set_rate(rate new_rate)
     {
         auto index = static_cast<unsigned int>(new_rate);
-        auto presc = adc_sample_rate_settings[index * 3] << 18;
-        auto smp = adc_sample_rate_settings[index * 3 + 1];
-        adc_gpt_divisor = adc_sample_rate_settings[index * 3 + 2];
+        auto plln = adc_sample_rate_settings[index * 4] << RCC_PLLSAI2CFGR_PLLSAI2N_Pos;
+        auto presc = adc_sample_rate_settings[index * 4 + 1] << ADC_CCR_PRESC_Pos;
+        auto smp = adc_sample_rate_settings[index * 4 + 2];
+        adc_gpt_divisor = adc_sample_rate_settings[index * 4 + 3];
     
         adcStop(adcd);
+
+        // Adjust PLLSAI2
+        RCC->CR &= ~(RCC_CR_PLLSAI2ON);
+        while ((RCC->CR & RCC_CR_PLLSAI2RDY) == RCC_CR_PLLSAI2RDY);
+        RCC->PLLSAI2CFGR = (RCC->PLLSAI2CFGR & ~(RCC_PLLSAI2CFGR_PLLSAI2N_Msk)) | plln;
+        RCC->CR |= RCC_CR_PLLSAI2ON;
+
         // Set ADC prescaler
-        adcd->adcc->CCR = (adcd->adcc->CCR & ~(0xF << 18)) | presc;
+        adcd->adcc->CCR = (adcd->adcc->CCR & ~(ADC_CCR_PRESC_Msk)) | presc;
         // Set sampling time
         adc_group_config.smpr[0] = ADC_SMPR1_SMP_AN5(smp);
         adcStart(adcd, &adc_config);
     }
+    
+    unsigned int get_rate()
+    {
+        for (unsigned int i = 0; i < ADC_SAMPLE_RATE_SETTINGS_COUNT; i++) {
+            if (adc_gpt_divisor == adc_sample_rate_settings[i * 3 + 3])
+                return i;
+        }
+
+        return 0xFF;
+    }
 
     unsigned int get_gpt_divisor()
     {
diff --git a/source/adc.hpp b/source/adc.hpp
index 5f41117..1431aa1 100644
--- a/source/adc.hpp
+++ b/source/adc.hpp
@@ -19,33 +19,18 @@ namespace adc
     using operation_t = void (*)(adcsample_t *buffer, size_t count);
 
     enum class rate : unsigned int {
-        R3125 = 0,
-        R3750,
-        R6250,
-        R7500,
-        R12K5,
-        R15K,
-        R25K,
-        R30K,
-        R40K,
-        R50K,
-        R60K,
-        R80K,
+        R16K = 0,
+        R48K,
         R96K,
         R100K,
-        R120K,
-        R160K,
-        R200K,
-        R240K,
         R400K,
-        R480K,
-        R800K,
-        R960K,
-        R1M6
+        R1M,
+        R2M
     };
     
     void init();
     void set_rate(rate new_rate);
+    unsigned int get_rate();
     unsigned int get_gpt_divisor();
     adcsample_t *read(adcsample_t *buffer, size_t count);
     void read_start(operation_t operation_func, adcsample_t *buffer, size_t count);
diff --git a/source/dac.cpp b/source/dac.cpp
index 1a7254a..ed4dce1 100644
--- a/source/dac.cpp
+++ b/source/dac.cpp
@@ -30,7 +30,7 @@ constexpr static const DACConversionGroup dac_group_config = {
 };
 
 constexpr static const GPTConfig gpt_config = {
-  .frequency = 14400000,
+  .frequency = 36000000,
   .callback = nullptr,
   .cr2 = TIM_CR2_MMS_1, /* TRGO */
   .dier = 0
diff --git a/source/main.cpp b/source/main.cpp
index 17b0adb..8948b8e 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -250,10 +250,16 @@ void main_loop()
                     break;
 
                 case 'r':
-                    if (usbserial::read(&cmd[1], 1) == 1)
-                        adc::set_rate(static_cast<adc::rate>(cmd[1]));
-                    else
+                    if (usbserial::read(&cmd[1], 1) == 1) {
+                        if (cmd[1] == 0xFF) {
+                            unsigned char r = static_cast<unsigned char>(adc::get_rate());
+                            usbserial::write(&r, 1);
+                        } else {
+                            adc::set_rate(static_cast<adc::rate>(cmd[1]));
+                        }
+                    } else {
                         error_queue_add(Error::BadParamSize);
+                    }
                     break;
 
                 // 'S' - Stops the continuous sampling/conversion.
@@ -267,6 +273,10 @@ void main_loop()
 
                 case 's':
                     if (dac_samples_new != nullptr) {
+                        auto samps = reinterpret_cast<const uint8_t *>(
+                            const_cast<const dacsample_t *>(dac_samples_new));
+                        dac_samples_new = nullptr;
+
                         unsigned char buf[2] = {
                             static_cast<unsigned char>(dac_sample_count / 2 & 0xFF),
                             static_cast<unsigned char>(((dac_sample_count / 2) >> 8) & 0xFF)
@@ -275,8 +285,6 @@ void main_loop()
                         unsigned int total = dac_sample_count / 2 * sizeof(dacsample_t);
                         unsigned int offset = 0;
                         unsigned char unused;
-                        auto samps = reinterpret_cast<const uint8_t *>(
-                            const_cast<const dacsample_t *>(dac_samples_new));
                         while (total > 512) {
                             usbserial::write(samps + offset, 512);
                             while (usbserial::read(&unused, 1) == 0);
@@ -285,7 +293,6 @@ void main_loop()
                         }
                         usbserial::write(samps + offset, total);
                         while (usbserial::read(&unused, 1) == 0);
-                        dac_samples_new = nullptr;
                     } else {
                         usbserial::write("\0\0", 2);
                     }