working visualisation that just shows the current waveform

Src/stm32f1xx_it.c

@@ -31,6 +31,7 @@
   ******************************************************************************
   */
 /* Includes ------------------------------------------------------------------*/
+#include <utils.h>
 #include "stm32f1xx_hal.h"
 #include "stm32f1xx.h"
 #include "stm32f1xx_it.h"
@@ -65,6 +66,7 @@ void NMI_Handler(void)
 void HardFault_Handler(void)
 {
   /* USER CODE BEGIN HardFault_IRQn 0 */
+	uart_print("Hard fault.\n");
 
   /* USER CODE END HardFault_IRQn 0 */
   while (1)
@@ -81,6 +83,7 @@ void HardFault_Handler(void)
 void MemManage_Handler(void)
 {
   /* USER CODE BEGIN MemoryManagement_IRQn 0 */
+	uart_print("MemManage fault.\n");
 
   /* USER CODE END MemoryManagement_IRQn 0 */
   while (1)
@@ -97,6 +100,7 @@ void MemManage_Handler(void)
 void BusFault_Handler(void)
 {
   /* USER CODE BEGIN BusFault_IRQn 0 */
+	uart_print("Bus fault.\n");
 
   /* USER CODE END BusFault_IRQn 0 */
   while (1)
@@ -113,6 +117,7 @@ void BusFault_Handler(void)
 void UsageFault_Handler(void)
 {
   /* USER CODE BEGIN UsageFault_IRQn 0 */
+	uart_print("Usage fault.\n");
 
   /* USER CODE END UsageFault_IRQn 0 */
   while (1)

Src/tim.c

@@ -50,7 +50,7 @@ void MX_TIM3_Init(void)
   htim3.Instance = TIM3;
   htim3.Init.Prescaler = 0;
   htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
-  htim3.Init.Period = 1800;
+  htim3.Init.Period = 6000;//1800
   htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
   if (HAL_TIM_OC_Init(&htim3) != HAL_OK)
   {

Src/user_main.c

@@ -4,6 +4,7 @@
 
 #include <inttypes.h>
 #include <stm32f1xx_hal_gpio.h>
+#include <dotmatrix.h>
 #include "mxconstants.h"
 #include "stm32f1xx_hal.h"
 #include "utils.h"
@@ -13,23 +14,37 @@
 
 static uint32_t audio_samples[256];
 
-void start_DMA() {
-	uart_print("- Starting ADC DMA\n");
+static DotMatrix_Cfg *disp;
 
-	HAL_ADC_Start_DMA(&hadc1, audio_samples, 256);
+void start_DMA() {
+	//uart_print("- Starting ADC DMA\n");
+
+	HAL_ADC_Start_DMA(&hadc1, audio_samples, 32);
 	HAL_TIM_Base_Start(&htim3);
 }
 
 /** This callback is called by HAL after the transfer is complete */
 void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef *hadc) {
-	uart_print("- DMA complete.\n");
+//	uart_print("- DMA complete.\n");
 
-	char x[100];
-	sprintf(x, "%"PRIu32"\n", audio_samples[0]);
-	uart_print(x);
+//	char x[100];
+//
+//	for (int i = 0; i < 256; i++) {
+//		sprintf(x, "%"PRIu32" ", audio_samples[i]);
+//		uart_print(x);
+//	}
+//	uart_print("\n");
+
+	dmtx_clear(disp);
+	for (int i = 0; i < 32; i++) {
+		dmtx_set(disp, i, ((audio_samples[i])>>6)-24, 1);
+	}
+	dmtx_show(disp);
 }
 
 void user_main() {
+	uart_print("== USER CODE STARTING ==\n");
+
 	// Leds OFF
 	HAL_GPIO_WritePin(LED1_GPIO_Port, LED1_Pin, 1);
 	HAL_GPIO_WritePin(LED2_GPIO_Port, LED2_Pin, 1);
@@ -39,13 +54,29 @@ void user_main() {
 	// Enable audio input
 	HAL_GPIO_WritePin(AUDIO_NSTBY_GPIO_Port, AUDIO_NSTBY_Pin, 1);
 
+	DotMatrix_Init disp_init;
+	disp_init.cols = 4;
+	disp_init.rows = 2;
+	disp_init.CS_GPIOx = SPI1_CS_GPIO_Port;
+	disp_init.CS_PINx = SPI1_CS_Pin;
+	disp_init.SPIx = SPI1;
+	disp = dmtx_init(&disp_init);
+
+	dmtx_intensity(disp, 2);
+
+	dmtx_clear(disp);
+	dmtx_show(disp);
+
 	while (1) {
 		// Blink
 		HAL_GPIO_TogglePin(LED1_GPIO_Port, LED1_Pin);
-		HAL_Delay(500);
+		HAL_Delay(50);
 
-		uart_print("Main loop\n");
+		//uart_print("Main loop\n");
 		start_DMA();
+
+		//dmtx_toggle(disp, 31, 15);
+		//dmtx_show(disp);
 	}
 }
 
@@ -64,7 +95,12 @@ void user_Error_Handler() {
    * @retval None
    */
 void user_assert_failed(uint8_t *file, uint32_t line) {
-	uart_print("Assert failed in file ");
+	user_error_file_line("Assert failed", (const char *) file, line);
+}
+
+void user_error_file_line(const char *message, const char *file, uint32_t line) {
+	uart_print(message);
+	uart_print(" in file ");
 	uart_print((char *) file);
 	uart_print(" on line ");