- NRF的引腳有 IRQ:中斷引腳 接收到數據或者發射數據完成的時候會被拉低 可以設置成引發中斷
- MOSI :SPI總線的數據發射引腳
- MISO :SPI 總線的數據接收引腳
- CS:低電平有效 SPI的片選引腳
- CE:NRF的發射或者接收選擇引腳
- SCK:SPI總線的時鐘線
- 有硬件SPI功能的MCU 可以忽略這部分
- typedef unsigned char uint8_t;
- uint8_t SPI_SR(uint8_t Data)
- {
- uint8_t i,buff=0;
- SCK_L;
- for(i=0;i<8;i++)
- {
- if(Data&0x80)
- MOSI_H;
- else
- MOSI_L;
- SCK_H;
- Data<<=1;
- buff++;
- if(MISO)
- buff++;
- SCK_L;
- }
- return Status;
- }
- uint8_t NRF_WriteReg(uint8_t reg,uint8_t data)
- {
- uint8_t Status;
- CS_L;
- CE_L;
- Status=SPI_SR(reg);
- SPI_SR(Data);
- CS_H;
- return Status;
- }
- uint8_t NRF_ReadReg(uint8_t reg)
- {
- uint8_t val;
- CS_L;
- CE_L;
- SPI_SR(reg);
- val=SPI_SR(0xff);
- CS_H;
- return val;
- }
- uint8_t NRF_WriteBuff(uint8_t reg,uint8_t *buff,uint8_t Byte)
- {
- uint8_t i,Status;
- CE_L;
- CS_L;
- Status=NRF_SR(reg);
- for(i=0;i<Byte;i++)
- SPI_SR(buff[i]);
- CS_H;
- return Status;
- }
- uint8_t NRF_ReadReg(uint8_t reg,uint8_t buff,uint8_t Byte)
- {
- uint8_t i,Status;
- CE_L;
- CS_L;
- Status=NRF_SR(reg);
- for(i=0;i<Byte,i++)
- buff[i]=SPI_SR(0xff);
- CS_H;
- return Status;
- }
- void NRF_SetMode(uint8_t flag) //1:發射,0接收
- {
- if(flag!=0)
- {
- NRF_CE_L;
- NRF_WriteBuff(NRF_WRITE_REG+RX_ADDR_P0,RX_ADDRESS,RX_ADR_WIDTH);//寫RX節點地址 //寄存器地址 地址 地址寬度
- NRF_WriteReg(NRF_WRITE_REG+EN_AA,0x01); //使能通道0的自動應答
- NRF_WriteReg(NRF_WRITE_REG+EN_RXADDR,0x01);//使能通道0的接收地址
- NRF_WriteReg(NRF_WRITE_REG+RF_CH,CHANAL); //設置RF通信頻率
- NRF_WriteReg(NRF_WRITE_REG+RX_PW_P0,RX_PLOAD_WIDTH);//選擇通道0的有效數據寬度
- NRF_WriteReg(NRF_WRITE_REG+RF_SETUP,0x0f); //設置TX發射參數,0db增益,2Mbps,低噪聲增益開啟
- NRF_WriteReg(NRF_WRITE_REG+CONFIG, 0x0f); //配置基本工作模式的參數;PWR_UP,EN_CRC,16BIT_CRC,接收模式
- /*CE拉高,進入接收模式*/
- NRF_CE_H;
- }
- else
- {
- NRF_CE_L;
- NRF_WriteBuff(NRF_WRITE_REG+TX_ADDR,TX_ADDRESS,TX_ADR_WIDTH); //寫TX節點地址
- NRF_WriteBuff(NRF_WRITE_REG+RX_ADDR_P0,RX_ADDRESS,RX_ADR_WIDTH); //設置TX節點地址,主要為了使能ACK
- NRF_WriteReg(NRF_WRITE_REG+EN_AA,0x01); //使能通道0的自動應答
- NRF_WriteReg(NRF_WRITE_REG+EN_RXADDR,0x01); //使能通道0的接收地址
- NRF_WriteReg(NRF_WRITE_REG+SETUP_RETR,0x1a);//設置自動重發間隔時間:500us + 86us;最大自動重發次數:10次
- NRF_WriteReg(NRF_WRITE_REG+RF_CH,CHANAL); //設置RF通道為CHANAL
- NRF_WriteReg(NRF_WRITE_REG+RF_SETUP,0x0f); //設置TX發射參數,0db增益,2Mbps,低噪聲增益開啟
- NRF_WriteReg(NRF_WRITE_REG+CONFIG,0x0e); //配置基本工作模式的參數;PWR_UP,EN_CRC,16BIT_CRC,發射模式,開啟所有中斷
- /*CE拉高,進入發送模式*/
- NRF_CE_H;
- Delay(0xffff); //CE要拉高一段時間才進入發送模式
- }
- }
復制代碼
- /**
- * @brief 用于向NRF的發送緩沖區中寫入數據
- * @param
- * @arg txBuf:存儲了將要發送的數據的數組,外部定義
- * @retval 發送結果,成功返回TXDS,失敗返回MAXRT或ERROR
- */
- uint8_t NRF_Tx_Data(uint8_t *txbuf)
- {
- uint8_t State;
- /*ce為低,進入待機模式1*/
- NRF_CE_L;
- /*寫數據到TX BUF 最大 32個字節*/
- NRF_WriteBuff(WR_TX_PLOAD,txbuf,TX_PLOAD_WIDTH);
- /*CE為高,txbuf非空,發送數據包 */
- NRF_CE_H;
-
- /*等待發送完成中斷 */
- while(NRF_IRQ!=0);
- /*讀取狀態寄存器的值 */
- State = NRF_ReadReg(STATUS);
- /*清除TX_DS或MAX_RT中斷標志*/
- NRF_WriteReg(NRF_WRITE_REG+STATUS,State);
- NRF_WriteReg(FLUSH_TX,NOP); //清除TX FIFO寄存器
- /*判斷中斷類型*/
- if(State&MAX_RT) //達到最大重發次數
- return MAX_RT;
- else if(State&TX_DS) //發送完成
- return TX_DS;
- else
- return ERROR; //其他原因發送失敗
- }
- /**
- * @brief 用于從NRF的接收緩沖區中讀出數據
- * @param
- * @arg rxBuf :用于接收該數據的數組,外部定義
- * @retval
- * @arg 接收結果
- */
- uint8_t NRF_Rx_Dat(uint8_t *rxbuf)
- {
- uint8_t State;
- NRF_CE_H; //進入接收狀態
- /*等待接收中斷*/
- while(NRF_IRQ!=0);
- NRF_CE_L; //進入待機狀態
- /*讀取status寄存器的值 */
- State=NRF_ReadReg(STATUS);
-
- /* 清除中斷標志*/
- NRF_WriteReg(NRF_WRITE_REG+STATUS,State);
- /*判斷是否接收到數據*/
- if(State&RX_DR) //接收到數據
- {
- NRF_ReadBuff(RD_RX_PLOAD,rxbuf,RX_PLOAD_WIDTH);//讀取數據
- NRF_WriteReg(FLUSH_RX,NOP); //清除RX FIFO寄存器
- return RX_DR;
- }
- else
- return ERROR; //沒收到任何數據
- }
- #define TX_ADR_WIDTH 5 //發射地址寬度
- #define TX_PLOAD_WIDTH 4 //發射數據通道有效數據寬度0~32Byte
- #define RX_ADR_WIDTH 5
- #define RX_PLOAD_WIDTH 4
- #define CHANAL 40 //頻道選擇
- // SPI(nRF24L01) commands , NRF的SPI命令宏定義,詳見NRF功能使用文檔
- #define NRF_READ_REG 0x00 // Define read command to register
- #define NRF_WRITE_REG 0x20 // Define write command to register
- #define RD_RX_PLOAD 0x61 // Define RX payload register address
- #define WR_TX_PLOAD 0xA0 // Define TX payload register address
- #define FLUSH_TX 0xE1 // Define flush TX register command
- #define FLUSH_RX 0xE2 // Define flush RX register command
- #define REUSE_TX_PL 0xE3 // Define reuse TX payload register command
- #define NOP 0xFF // Define No Operation, might be used to read status register
- // SPI(nRF24L01) registers(addresses) ,NRF24L01 相關寄存器地址的宏定義
- #define CONFIG 0x00 // 'Config' register address
- #define EN_AA 0x01 // 'Enable Auto Acknowledgment' register address
- #define EN_RXADDR 0x02 // 'Enabled RX addresses' register address
- #define SETUP_AW 0x03 // 'Setup address width' register address
- #define SETUP_RETR 0x04 // 'Setup Auto. Retrans' register address
- #define RF_CH 0x05 // 'RF channel' register address
- #define RF_SETUP 0x06 // 'RF setup' register address
- #define STATUS 0x07 // 'Status' register address
- #define OBSERVE_TX 0x08 // 'Observe TX' register address
- #define CD 0x09 // 'Carrier Detect' register address
- #define RX_ADDR_P0 0x0A // 'RX address pipe0' register address
- #define RX_ADDR_P1 0x0B // 'RX address pipe1' register address
- #define RX_ADDR_P2 0x0C // 'RX address pipe2' register address
- #define RX_ADDR_P3 0x0D // 'RX address pipe3' register address
- #define RX_ADDR_P4 0x0E // 'RX address pipe4' register address
- #define RX_ADDR_P5 0x0F // 'RX address pipe5' register address
- #define TX_ADDR 0x10 // 'TX address' register address
- #define RX_PW_P0 0x11 // 'RX payload width, pipe0' register address
- #define RX_PW_P1 0x12 // 'RX payload width, pipe1' register address
- #define RX_PW_P2 0x13 // 'RX payload width, pipe2' register address
- #define RX_PW_P3 0x14 // 'RX payload width, pipe3' register address
- #define RX_PW_P4 0x15 // 'RX payload width, pipe4' register address
- #define RX_PW_P5 0x16 // 'RX payload width, pipe5' register address
- #define FIFO_STATUS 0x17 // 'FIFO Status Register' register address
- #define MAX_RT 0x10 //達到最大重發次數中斷標志位
- #define TX_DS 0x20 //發送完成中斷標志位 //
- #define RX_DR 0x40 //接收到數據中斷標志位
復制代碼
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