Cannot get SPI communication with SD Card to work (but works on arduino) Hi everyone,I'm trying to interface an SD card over SPI with an STM32F411. However, I cannot even initialize it. My current sequence is:Wait 20 ms after power-on.Send 10 clock cycles with CS high.Pull CS low and send CMD0 and wait for a reponse.Instead, I only ever receive 0xFF instead of 0x01.My SPI configuration looks like this:Here is the relevant code: MY_DEBUG_PRINTLN("Hello World");
uint8_t txBuf[6];
uint8_t resp = 0x00;
uint8_t dummy = 0xFF;
HAL_Delay(20);
MY_DEBUG_PRINT("Raw SD SPI test:\n");
// send 80 clocks with CS high
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_SET);
for (int i = 0; i < 10; i++) {
HAL_SPI_Transmit(&hspi2, &dummy, 1, HAL_MAX_DELAY);
}
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_RESET);
// CMD0 frame
txBuf[0] = 0x40;
txBuf[1] = 0x00;
txBuf[2] = 0x00;
txBuf[3] = 0x00;
txBuf[4] = 0x00;
txBuf[5] = 0x95;
// send command
HAL_SPI_Transmit(&hspi2, txBuf, 6, HAL_MAX_DELAY);
// wait for response
for (int i = 0; i < 3
