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SPI master problem

Hi,

I am using nrf52833 EVB as an SPI master. The data is sent properly and well-received at the slave, however, I have a problem with the data received.

The problem is that every second transaction I get the wrong data. For example if the slave is sending a growing counter the data received will look like this:

0, 128, 2, 128, 4, 0, 128 .......

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#include "nrf_drv_spi.h"
#include "app_util_platform.h"
#include "nrf_gpio.h"
#include "nrf_delay.h"
#include "boards.h"
#include "app_error.h"
#include <string.h>
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
#include "nrf_gpio.h"
#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[] = {0xFF}; /**< TX buffer. */
static uint8_t m_rx_buf[1]; /**< RX buffer. */
static const uint8_t m_length = sizeof(m_tx_buf); /**< Transfer length. */
int counter = 0;
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Can anyone explain

I don't experience this problem when using RPI as SPI master with the same slave.

Anyone?