Using the SPI example to communicate with a CR95HF

[PaulP]

Good evening all, I'm trying to get my DK52 communicating with a CR95HF (this is a NFC controller with serial and SPI control interfaces), I'm using a breakout board - BM019
The CR95 requires a setup sequence to select the SPI interface

So far I'm using the SPI example from SDK 14, I have modified it to toggle the IRQ_IN pin I'm using pin30) on initialization, I then attempt to send 0x55 to the CR95 (this is a Echo command - I'm expecting 0x55 back). However I seem to get back 0x06 (the first two loops) then nothing for any additional requests)

I have tried removing my initialization toggle, when I do this I don't get anything back on any of the loops)

Here's my modified code.

#define SPI_INSTANCE  0
static const nrf_drv_spi_t spi = NRF_DRV_SPI_INSTANCE(SPI_INSTANCE);  
static volatile bool spi_xfer_done; 

//#define TEST_STRING "Nordic"
//static uint8_t       m_tx_buf[] = TEST_STRING;      
static uint8_t       m_rx_buf[2];  //sizeof(TEST_STRING) + 1];   
static const uint8_t m_length = 1; //sizeof(m_tx_buf);        

void spi_event_handler(nrf_drv_spi_evt_t const * p_event,
                       void *                    p_context)
{
    spi_xfer_done = true;
    NRF_LOG_INFO("Transfer completed.");
    if (m_rx_buf[0] != 0)
    {
        NRF_LOG_INFO(" Received:");
        NRF_LOG_HEXDUMP_INFO(m_rx_buf, strlen((const char *)m_rx_buf));
    }
}

uint8_t hexdata = 0x55;

int main(void)
{
    bsp_board_leds_init();

    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
    NRF_LOG_DEFAULT_BACKENDS_INIT();
    nrf_gpio_cfg_output(30);
    nrf_gpio_cfg_output(29);
    nrf_gpio_pin_set(30);
    nrf_delay_ms(3000);
    NRF_LOG_INFO("SPI example.");

    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;
    
   nrf_gpio_pin_clear(30);
    nrf_delay_us(100) ;        // BM019 into SPI
    nrf_gpio_pin_set(30);
    nrf_delay_ms(10) ;
    APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, spi_event_handler, NULL));
    nrf_delay_ms(1000);
    
    while (1)
    {
        // Reset rx buffer and transfer done flag
        memset(m_rx_buf, 0, m_length);
        spi_xfer_done = false;
        APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi, &hexdata, m_length, m_rx_buf, m_length));
        while (!spi_xfer_done)
        {
            __WFE();
        }

        NRF_LOG_FLUSH();

        bsp_board_led_invert(BSP_BOARD_LED_0);
        nrf_delay_ms(1000);
    }
}

and my output.

<info> app: SPI example.
<info> app: Transfer completed.
<info> app:  Received:
<info> app:  06                     |.       
<info> app: Transfer completed.
<info> app:  Received:
<info> app:  06                     |.       
<info> app: Transfer completed.
<info> app: Transfer completed.
<info> app: Transfer completed.
<info> app: Transfer completed.

I have tried so many thing I'm starting to lose my mind on what I've done! (2 days now!!!) I think i'm initializing it but not 100% sure. I get that this might be a bit out of scope on the Nordic site but I'm thinking this is more a SDK issue!