diff options
Diffstat (limited to 'Core/Src/main.c')
| -rw-r--r-- | Core/Src/main.c | 78 |
1 files changed, 61 insertions, 17 deletions
diff --git a/Core/Src/main.c b/Core/Src/main.c index 45d16a6..ed49703 100644 --- a/Core/Src/main.c +++ b/Core/Src/main.c @@ -32,7 +32,7 @@ typedef uint32_t sample_t; /* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
-#define SAMPLE_COUNT (256) // (Stereo!) Sample count per half-transfer
+#define SAMPLE_COUNT (1024) // (Stereo!) Sample count per half-transfer
#define SAMPLES_PER_REPORT (48000) // Report every second given our 48 kHz rate
#define MIC_OFFSET_DB ( 0.f) // Linear offset
#define MIC_SENSITIVITY (-26.f) // dBFS value expected at MIC_REF_DB
@@ -79,7 +79,9 @@ static HAL_StatusTypeDef HAL_SPI_TransmitReceive_DMA_Mixed( uint8_t *pRxData,
uint16_t TxSize,
uint16_t RxSize);
+__RAM_FUNC
static void SPI_DMATransmitReceiveCplt(DMA_HandleTypeDef *hdma);
+__RAM_FUNC
static void SPI_DMAHalfTransmitReceiveCplt(DMA_HandleTypeDef *hdma);
/* USER CODE END PFP */
@@ -91,6 +93,14 @@ int __io_putchar(int ch) HAL_UART_Transmit(&huart2, &buf, sizeof(buf), HAL_TIMEOUT);
return buf;
}
+
+__RAM_FUNC
+void fvar_init(void)
+{
+ ln10 = qfp_fln(10.f);
+ MIC_REF_AMPL = qfp_fmul(qfp_int2float((1u << (MIC_BITS - 2)) - 1),
+ qfp_fpow(10.f, MIC_SENSITIVITY / 20.f));
+}
/* USER CODE END 0 */
/**
@@ -101,9 +111,7 @@ int main(void) {
/* USER CODE BEGIN 1 */
- ln10 = qfp_fln(10.f);
- MIC_REF_AMPL = qfp_fmul(qfp_int2float((1u << (MIC_BITS - 1)) - 1),
- qfp_fpow(10.f, MIC_SENSITIVITY / 20.f));
+ fvar_init();
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
@@ -160,7 +168,7 @@ void SystemClock_Config(void) /** Configure the main internal regulator output voltage
*/
- HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE2);
+ HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
@@ -180,10 +188,10 @@ void SystemClock_Config(void) RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
- RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV2;
- RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
+ RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+ RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
- if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
+ if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
Error_Handler();
}
@@ -323,7 +331,7 @@ static void MX_GPIO_Init(void) HAL_GPIO_WritePin(LED_RED_GPIO_Port, LED_RED_Pin, GPIO_PIN_RESET);
/*Configure GPIO pin Output Level */
- HAL_GPIO_WritePin(IDLE_GPIO_Port, IDLE_Pin, GPIO_PIN_RESET);
+ HAL_GPIO_WritePin(IDLE_GPIO_Port, IDLE_Pin, GPIO_PIN_SET);
/*Configure GPIO pin : LED_GREEN_Pin */
GPIO_InitStruct.Pin = LED_GREEN_Pin;
@@ -443,6 +451,43 @@ error : #define BITO (10)
+__RAM_FUNC
+__attribute__((naked))
+int64_t lmul(int64_t a, int64_t b)
+{
+ asm(
+" push {r4, lr}\n"
+" mul r1, r2\n"
+" mul r3, r0\n"
+" add r1, r3\n"
+
+" lsr r3, r0, #16\n"
+" lsr r4, r2, #16\n"
+" mul r3, r4\n"
+" add r1, r3\n"
+
+" lsr r3, r0, #16\n"
+" uxth r0, r0\n"
+" uxth r2, r2\n"
+" mul r3, r2\n"
+" mul r4, r0\n"
+" mul r0, r2\n"
+
+" mov r2, #0\n"
+" add r3, r4\n"
+" adc r2, r2\n"
+" lsl r2, #16\n"
+" add r1, r2\n"
+
+" lsl r2, r3, #16\n"
+" lsr r3, #16\n"
+" add r0, r2\n"
+" adc r1, r3\n"
+" pop {r4, pc}\n"
+ );
+}
+
+__RAM_FUNC
static inline void process(int64_t in_div4)
{
static int64_t z[4] = {0, 0, 0, 0};
@@ -458,25 +503,24 @@ static inline void process(int64_t in_div4) int64_t out3 = (out2 + z[3]);
z[3] = ((out3 * 0x3f1 /*0.985f*/) >> BITO) - out2;
- DB_Sum_Squares += (out3 * out3) >> BITO;
+ DB_Sum_Squares += lmul(out3, out3) >> BITO;
}
+__RAM_FUNC
static void processSampleBlock(sample_t *sample)
{
- HAL_GPIO_WritePin(IDLE_GPIO_Port, IDLE_Pin, GPIO_PIN_RESET);
-
-#define STRIDE 2
+ IDLE_GPIO_Port->ODR ^= IDLE_Pin;
- for (int i = 0; i < SAMPLE_COUNT; i += 2 * STRIDE) {
+ for (int i = 0; i < SAMPLE_COUNT; i += 2) {
// 18-bit sample comes in as big-endian with right padding.
// Use REVSH to extract 18-bit reading divided by four for process().
int samp;
asm("revsh %0, %1" : "=l" (samp) : "l" (sample[i]));
process(samp);
}
- DB_Count += SAMPLE_COUNT / (2 * STRIDE);
+ DB_Count += SAMPLE_COUNT / 2;
- if (DB_Count >= SAMPLES_PER_REPORT / STRIDE) {
+ if (DB_Count >= SAMPLES_PER_REPORT) {
float rms = qfp_fsqrt(qfp_int2float((DB_Sum_Squares >> BITO) / DB_Count));
float db = qfp_fadd(qfp_fmul(qfp_flog10(qfp_fdiv(rms, MIC_REF_AMPL)), 20.f),
MIC_OFFSET_DB + MIC_REF_DB);
@@ -486,7 +530,7 @@ static void processSampleBlock(sample_t *sample) printf("%d dB\r\n", qfp_float2int(db));
}
- HAL_GPIO_WritePin(IDLE_GPIO_Port, IDLE_Pin, GPIO_PIN_SET);
+ IDLE_GPIO_Port->ODR ^= IDLE_Pin;
}
void SPI_DMATransmitReceiveCplt(DMA_HandleTypeDef *hdma)
|