STM32f030与RA-02模块SPI通讯代码实现

以下是STM32f030与RA-02模块SPI通讯的代码实现：

#include "stm32f0xx.h"

#define RA02_NSS_PIN GPIO_Pin_4
#define RA02_NSS_GPIO GPIOA
#define RA02_RESET_PIN GPIO_Pin_3
#define RA02_RESET_GPIO GPIOA
#define RA02_SPI SPI1

void RA02_Init(void)
{
    //初始化SPI1
    SPI_InitTypeDef SPI_InitStruct;
    GPIO_InitTypeDef GPIO_InitStruct;
    
    //使能SPI1和GPIOA时钟
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1 | RCC_APB2Periph_GPIOA, ENABLE);
    
    //配置SPI1引脚
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOA, &GPIO_InitStruct);
    
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_0);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_0);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_0);
    
    //配置NSS引脚和RESET引脚
    GPIO_InitStruct.GPIO_Pin = RA02_NSS_PIN | RA02_RESET_PIN;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(RA02_NSS_GPIO, &GPIO_InitStruct);
    
    //将NSS引脚拉高
    GPIO_SetBits(RA02_NSS_GPIO, RA02_NSS_PIN);
    
    //将RESET引脚拉低
    GPIO_ResetBits(RA02_RESET_GPIO, RA02_RESET_PIN);
    delay_ms(10);
    GPIO_SetBits(RA02_RESET_GPIO, RA02_RESET_PIN);
    delay_ms(100);
    
    //配置SPI1
    SPI_StructInit(&SPI_InitStruct);
    SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
    SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge;
    SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low;
    SPI_InitStruct.SPI_CRCPolynomial = 7;
    SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b;
    SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
    SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;
    SPI_InitStruct.SPI_Mode = SPI_Mode_Master;
    SPI_InitStruct.SPI_NSS = SPI_NSS_Soft;
    SPI_Init(RA02_SPI, &SPI_InitStruct);
    
    SPI_Cmd(RA02_SPI, ENABLE);
}

uint8_t RA02_ReadReg(uint8_t addr)
{
    uint8_t reg_val = 0;
    
    //拉低NSS引脚
    GPIO_ResetBits(RA02_NSS_GPIO, RA02_NSS_PIN);
    
    //发送读寄存器命令
    SPI_SendData8(RA02_SPI, 0x80 | addr);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_TXE) == RESET);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_RXNE) == RESET);
    reg_val = SPI_ReceiveData8(RA02_SPI);
    
    //发送一个字节来读取寄存器值
    SPI_SendData8(RA02_SPI, 0x00);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_TXE) == RESET);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_RXNE) == RESET);
    reg_val = SPI_ReceiveData8(RA02_SPI);
    
    //拉高NSS引脚
    GPIO_SetBits(RA02_NSS_GPIO, RA02_NSS_PIN);
    
    return reg_val;
}

void RA02_WriteReg(uint8_t addr, uint8_t val)
{
    //拉低NSS引脚
    GPIO_ResetBits(RA02_NSS_GPIO, RA02_NSS_PIN);
    
    //发送写寄存器命令
    SPI_SendData8(RA02_SPI, addr);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_TXE) == RESET);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_RXNE) == RESET);
    SPI_ReceiveData8(RA02_SPI);
    
    //发送一个字节来写入寄存器值
    SPI_SendData8(RA02_SPI, val);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_TXE) == RESET);
    while(SPI_I2S_GetFlagStatus(RA02_SPI, SPI_I2S_FLAG_RXNE) == RESET);
    SPI_ReceiveData8(RA02_SPI);
    
    //拉高NSS引脚
    GPIO_SetBits(RA02_NSS_GPIO, RA02_NSS_PIN);
}

这段代码中，我们首先需要定义RA-02模块的NSS引脚和RESET引脚，以及使用的SPI口（这里使用的是SPI1）。然后在`RA02_Init`函数中初始化SPI1和NSS引脚、RESET引脚，并将NSS引脚拉高，RESET引脚拉低一段时间，再拉高。最后，我们可以使用`RA02_ReadReg`和`RA02_WriteReg`函数来读取和写入RA-02模块的寄存器。在这两个函数中，我们需要先拉低NSS引脚，然后发送读/写寄存器命令和寄存器地址，再发送一个字节来读取或写入寄存器值，最后再拉高NSS引脚。