nrf51822 Flash SPI Test

static uint8_t tx_data[1]; /**< SPI TX buffer. */
static uint8_t rx_data[1]; /**< SPI RX buffer. */
static uint8_t id[3]; /**< SPI RX buffer. */

/**@brief Function for application main entry.
 */
int main(void)
{
	//connect
	spi_base_address = spi_master_init(SFLASH_SPI, SPI_MODE0, (bool)0);

	//send the 'get id' code
	tx_data[0] = 0x9f;
	rx_data[0] = 0x0;
	spi_master_tx_rx(spi_base_address, 1, (const uint8_t *)tx_data, rx_data);

	//read the first byte back
	tx_data[0] = 0xff;
	rx_data[0] = 0x0;
	spi_master_tx_rx(spi_base_address, 1, (const uint8_t *)tx_data, rx_data);
	id[0] = rx_data[0];

	//read the second byte back
	tx_data[0] = 0xff;
	rx_data[0] = 0x0;
	spi_master_tx_rx(spi_base_address, 1, (const uint8_t *)tx_data, rx_data);
	id[1] = rx_data[0];

	//read the third byte back
	tx_data[0] = 0xff;
	rx_data[0] = 0x0;
	spi_master_tx_rx(spi_base_address, 1, (const uint8_t *)tx_data, rx_data);
	id[2] = rx_data[0];
}