nRF51x22 SPI Master Driver

1. 簡單替nRF51822 SPI Driver做個備份.

2. 本範例搭配ST LIS3DH Sensor Board測試使用.

3. 需先include spi_master.c 和 spi_master.h, 路徑在 \app\components\drivers_nrf\spi_master\ 底下.

4. spi_master.c 和 spi_master.h 的下載連結:

    spi_master.c

    spi_master.h

5. code:

spi_example.h

#include "app_util_platform.h"
#include "bsp.h"
#include "spi_master.h"

bool SPI_Write( uint8_t register_address, uint8_t *value, uint8_t number_of_bytes );
bool SPI_Read( uint8_t register_address, uint8_t *destination, uint8_t number_of_bytes );

spi_example.c

#include "spi_example.h"


static void spi_master_init(spi_master_hw_instance_t   spi_master_instance )
{
    uint32_t err_code = NRF_SUCCESS;

    // Configure SPI master.
    spi_master_config_t spi_config = SPI_MASTER_INIT_DEFAULT;
    spi_config.SPI_CONFIG_CPHA=SPI_CONFIG_CPHA_Leading ;
    spi_config.SPI_CONFIG_CPOL=SPI_CONFIG_CPOL_ActiveHigh;
    spi_config.SPI_Pin_SCK  = SPIM0_SCK_PIN;
    spi_config.SPI_Pin_MISO = SPIM0_MISO_PIN;
    spi_config.SPI_Pin_MOSI = SPIM0_MOSI_PIN;
    spi_config.SPI_Pin_SS   = SPIM0_SS_PIN;
    spi_config.SPI_Freq     = SPI_FREQUENCY_FREQUENCY_M4;
    spi_config.SPI_CONFIG_ORDER = SPI_CONFIG_ORDER_MsbFirst;
    spi_config.SPI_PriorityIRQ = APP_IRQ_PRIORITY_LOW;
    spi_config.SPI_DisableAllIRQ = 0;
    err_code = spi_master_open(spi_master_instance, &spi_config);
    APP_ERROR_CHECK(err_code);
}

static void spi_send_recv(const spi_master_hw_instance_t spi_master_hw_instance, uint8_t * const p_tx_data, uint8_t * const p_rx_data, const uint16_t len)
{
    
    // Start transfer.
  spi_master_init(spi_master_hw_instance);
    uint32_t err_code = spi_master_send_recv(spi_master_hw_instance, p_tx_data, len, p_rx_data, len);
    APP_ERROR_CHECK(err_code);
  for (int i = 0 ; i < 1000 ; i++ ) {
   if ( spi_master_get_state(spi_master_hw_instance) != SPI_MASTER_STATE_BUSY )
    break;
  }
  spi_master_close(spi_master_hw_instance);
}

bool SPI_Write( uint8_t register_address, uint8_t *value, uint8_t number_of_bytes )
{
  #define i2c_write_data_len 6
 
  uint8_t w2_data[i2c_write_data_len+1];
  uint8_t r2_data[i2c_write_data_len+1];
  uint8_t i;

  if(number_of_bytes > 0x01)
  {
   register_address |= (uint8_t)MULTIPLEBYTE_CMD;
  }
 
  w2_data[0] = register_address;
  for ( i = 0 ; i < number_of_bytes ; i++ ) {
   w2_data[i+1] = value[i];
  }

  spi_send_recv(SPI_MASTER_0, w2_data, r2_data, number_of_bytes +1);

                return true;
}

bool SPI_Read(uint8_t register_address, uint8_t * destination, uint8_t number_of_bytes)
{
 
  #define i2c_read_data_len 8

  uint8_t w2_data[i2c_write_data_len+1];
  uint8_t r2_data[i2c_write_data_len+1];
  uint8_t i;

  if(number_of_bytes > 0x01)
  {
   register_address |= (uint8_t)(READWRITE_CMD | MULTIPLEBYTE_CMD);
  }
  else
  {
   register_address |= (uint8_t)READWRITE_CMD;
  }
 
  w2_data[0] = register_address;
  spi_send_recv(SPI_MASTER_0, w2_data, r2_data, number_of_bytes+1);
 
  for( i = 0 ; i < number_of_bytes ; i++ ) {
   destination[i] = r2_data[i+1];
  }

                return true;
}

6. example-1:  read WHO_AM_I register(0x0F) from LIS3DH.

#define  LIS3DH_REGISTER_WHO_AM_I             0x0F

void Read_LIS3DH_WHOAMI_Register(void)
{
 uint8_t temp[6];
 
 SPI_Read(LIS3DH_REGISTER_WHO_AM_I, temp, 1);
 if ( temp[0] == 0x33 ) {
   while(1);
 }
}

7. example-2: Enable LIS3DH Sensor.

#define  LIS3DH_CTRL_REG1_DATARATE_100HZ      0x50
#define  LIS3DH_CTRL_REG1_XYZEN               0x07
#define  LIS3DH_REGISTER_CTRL_REG1            0x20

void Enable_LIS3DH_Sensor(void)
{
 uint8_t temp[6];
 
 temp[0] = (LIS3DH_CTRL_REG1_DATARATE_100HZ | LIS3DH_CTRL_REG1_XYZEN);
 SPI_Write( LIS3DH_REGISTER_CTRL_REG1, temp, 1 );
 
}