I am trying to implement an EEPROM driver which uses DMA. So far, I can implement polling and interrupt version. HAL_SPI_Transmit_DMA works OK, but HAL_SPI_Receive_DMA returns HAL_BUSY, so even the first reading process seams OK, it actually doesn't and I cannot read the bytes that I wrote just before the reading operation.
/* Private variables ---------------------------------------------------------*/
SPI_HandleTypeDef hspi2;
DMA_HandleTypeDef hdma_spi2_tx;
DMA_HandleTypeDef hdma_spi2_rx;
int main(void)
{
/* USER CODE BEGIN 1 */
uint8_t data[40];
uint8_t output_data[40];
/* USER CODE END 1 */
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_DMA_Init();
MX_SPI2_Init();
/* USER CODE BEGIN 2 */
fill_data(data, 40);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
for (int var = 0; var < some_byte_number; ++var) {
eeprom_write_func(address, data);
address++;
}
address = 0x0000;
for (int var = 0; var < some_byte_number; ++var) {
eeprom_read_func(address, output_data);
address++;
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
static void MX_SPI2_Init(void)
{
/* USER CODE BEGIN SPI2_Init 0 */
/* USER CODE END SPI2_Init 0 */
/* USER CODE BEGIN SPI2_Init 1 */
/* USER CODE END SPI2_Init 1 */
/* SPI2 parameter configuration*/
hspix.Instance = SPIx;
hspix.Init.Mode = SPI_MODE_MASTER;
hspix.Init.Direction = SPI_DIRECTION_2LINES;
hspix.Init.DataSize = SPI_DATASIZE_8BIT;
hspix.Init.CLKPolarity = SPI_POLARITY_LOW;
hspix.Init.CLKPhase = SPI_PHASE_1EDGE;
hspix.Init.NSS = SPI_NSS_SOFT;
hspix.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_8;
hspix.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspix.Init.TIMode = SPI_TIMODE_DISABLE;
hspix.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspix.Init.CRCPolynomial = 10;
if (HAL_SPI_Init(&hspix) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN SPI2_Init 2 */
/* USER CODE END SPI2_Init 2 */
}
uint8_t eeprom_read_function(uint16_t address, uint8_t *output)
{
uint8_t spi_status;
uint8_t dmarx_status;
uint8_t dmatx_status;
// Some configuration of eeprom
if (HAL_SPI_Receive_DMA(hspix, output, 1) != HAL_OK) // read 1 byte
{
spi_status = HAL_SPI_GetState(&hspix); // -> returns HAL_BUSY
dmarx_status = HAL_DMA_GetStatus((&hspix)->hdmarx)); // -> returns HAL_OK
dmatx_status = HAL_DMA_GetStatus((&hspix)->hdmatx)); // -> returns HAL_OK
}
}
I give some portion of the code. As I mentioned, even my writing function seems OK( the DMA functions don't returns HAL_BUSY or sth equivalent), the read function returns HAL_BUSY in the first iteration. Both my read and write functions are in DMA mode which are being operated in normal mode, data width for both peripheral and memory is word, and memory increment is enabled while peripheral increment is disabled.
