Unable to interface nrf51822 with LIS3DH (accelerometer) using SPI being nrf as master

Hi, 

I tried interfacing LIS3Dh using SPI, I used the SPI example to start with, when I didn't get the desired result, I look numerous question on the forum and tried to modify the code but it does not seem to be working.

I am simply trying to read WHO_AM_I register/or any other register, I am getting FF always, 

the sensor is embedded on PCB with following configurations: 

Configurations:

LIS3DH nrf 51822 pin  sdk_config.h 
SCK 9 SPI_SCK_PIN 9
SDI 10 SPI_MOSI_PIN 10
CS 12 SPI_SS_PIN 12
SDO 7 SPI_MISO_PIN 11

Below code is trying to read who_am_i ( 0x0F) 

#define SPI_INSTANCE  0 /**< SPI instance index. */
static const nrf_drv_spi_t spi = NRF_DRV_SPI_INSTANCE(SPI_INSTANCE);  /**< SPI instance. */
static volatile bool spi_xfer_done;  /**< Flag used to indicate that SPI instance completed the transfer. */

#define TEST_STRING "Nordic"
static uint8_t       m_tx_buf[]={0x0F};           /**< TX buffer. */
static uint8_t       m_rx_buf[]={0x00, 0x00,0x00, 0x00,0x00};    /**< RX buffer. */
//static const uint8_t m_length = sizeof(m_rx_buf);        /**< Transfer length. */

/**
 * @brief SPI user event handler.
 * @param event
 */
void spi_event_handler(nrf_drv_spi_evt_t const * p_event)
{
    spi_xfer_done = true;
    SEGGER_RTT_printf(0,"Transfer completed.\r\n");
    if (1 != 0)
    {
        SEGGER_RTT_printf(0," Received: \r\n");
        NRF_LOG_HEXDUMP_INFO(m_rx_buf, strlen((const char *)m_rx_buf));
        SEGGER_RTT_printf(0, "value: %u \r\n", *m_rx_buf);
        bsp_board_led_invert(BSP_BOARD_LED_1);
    }
}

int main(void)
{
    bsp_board_leds_init();

    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));

    SEGGER_RTT_printf(0,"SPI example\r\n");

   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.frequency= NRF_DRV_SPI_FREQ_8M;
	spi_config.mode= NRF_DRV_SPI_MODE_2;
        
	APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, spi_event_handler));
        
       
        uint8_t sizerx = 2;
        spi_xfer_done = false;
        
        APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi, m_tx_buf, 1, m_rx_buf, sizerx));
        while (!spi_xfer_done){
	  __WFE();
        }

        if(sizerx!=0)
        {
            SEGGER_RTT_printf(0,"Received[0]: %x %x %x %x %x \n\r",m_rx_buf[0],m_rx_buf[1],m_rx_buf[2],m_rx_buf[3],m_rx_buf[4]);
        }else{
            SEGGER_RTT_printf(0,"no value return from \r\n");
        }
      
      SEGGER_RTT_printf(0,"miso-> %u \r\n", nrf_gpio_pin_out_read(11));
      SEGGER_RTT_printf(0,"mosi-> %u \r\n", nrf_gpio_pin_out_read(10));
      SEGGER_RTT_printf(0,"ss-> %u \r\n", nrf_gpio_pin_out_read(12));
                     
}

log output ( in every case I am getting FF value in rx_buff ) 

SDK Used: 12.2

using JLink to transfer the via SWO

I have tried with different modes and frequencies also but no luck. 

Please help.

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