Hi everyone,
I am seeing an issue where the SPI (master) ignores the first byte of RX buff and begins storing the received bytes from RxBuff[1] instead of RxBuff[0]. In addition to ignoring the first RX byte, the first clock cycles for RxBuff[0] is missing as well (i.e., instead of having 1 TX + 4 RX clock cycles for the below code example, there are only 1 TX + 3 RX; verified on the oscilloscope). I was not using any SoftDevice and the only peripherals used were app timers, UART, and of course SPI.
Below is the code I used for initialization and transferring bytes via SPI:
nrf_drv_spi_config_t spi_config; //= NRF_DRV_SPI_DEFAULT_CONFIG;
spi_config.ss_pin = SPI_SS_PIN;
spi_config.miso_pin = SPI_MISO_PIN;
spi_config.mosi_pin = SPI_MOSI_PIN;
spi_config.sck_pin = SPI_SCK_PIN;
spi_config.orc = 0xFF;
spi_config.frequency = NRF_DRV_SPI_FREQ_4M;
spi_config.mode = NRF_DRV_SPI_MODE_0;
spi_config.bit_order = NRF_DRV_SPI_BIT_ORDER_MSB_FIRST;
// set our SPI0 configuration
APP_ERROR_CHECK(nrf_drv_spi_init(&SPI0, &spi_config, SpiEventHandler, NULL));
...
void SpiEventHandler(nrf_drv_spi_evt_t const *p_event, void *p_context)
{
// do nothing for now...
return;
}
...
uint8_t TxBuff[5];
uint8_t RxBuff[20];
nrf_drv_spi_transfer(&SPI0, TxBuff, 1, RxBuff, 4);
Thank you for your help!
