|
- #include <reg51.h>
- #define uchar unsigned char
- #define uint unsigned int
- sbit CE = P1^0; // Chip Enable pin signal (output)
- sbit CSN = P1^1; // Slave Select pin, (output to CSN, nRF24L01)
- sbit IRQ = P1^5; // Interrupt signal, from nRF24L01 (input)
- sbit MISO = P1^4; // Master In, Slave Out pin (input)
- sbit MOSI = P1^3; // Serial Clock pin, (output)
- sbit SCK = P1^2; // Master Out, Slave In pin (output)
- // SPI(nRF24L01) commands
- #define READ_REG 0x00 // Define read command to register
- #define 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)
- #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 TX_ADR_WIDTH 5 // 5字節(jié)寬度的發(fā)送/接收地址
- #define TX_PLOAD_WIDTH 4 // 數(shù)據(jù)通道有效數(shù)據(jù)寬度
- uchar code TX_ADDRESS[TX_ADR_WIDTH] = {0x34,0x43,0x10,0x10,0x01}; // 定義一個(gè)靜態(tài)發(fā)送地址
- uchar RX_BUF[TX_PLOAD_WIDTH];
- uchar TX_BUF[TX_PLOAD_WIDTH];
- uchar flag;
- uchar DATA = 0x01;
- uchar bdata sta;
- sbit RX_DR = sta^6;
- sbit TX_DS = sta^5;
- sbit MAX_RT = sta^4;
- void init_io(void)
- {
- CE = 0; // 待機(jī)
- CSN = 1; // SPI禁止
- SCK = 0; // SPI時(shí)鐘置低
- IRQ = 1; // 中斷復(fù)位
- }
- void delay_ms(uchar x)
- {
- uchar i, j;
- i = 0;
- for(i=0; i<x; i++)
- {
- j = 250;
- while(--j);
- j = 250;
- while(--j);
- }
- }
- uchar SPI_RW(uchar byte)
- {
- uchar i;
- for(i=0; i<8; i++) // 循環(huán)8次
- {
- MOSI = (byte & 0x80); // byte最高位輸出到MOSI
- byte <<= 1; // 低一位移位到最高位
- SCK = 1; // 拉高SCK,nRF24L01從MOSI讀入1位數(shù)據(jù),同時(shí)從MISO輸出1位數(shù)據(jù)
- byte |= MISO; // 讀MISO到byte最低位
- SCK = 0; // SCK置低
- }
- return(byte); // 返回讀出的一字節(jié)
- }
- uchar SPI_RW_Reg(uchar reg, uchar value)
- {
- uchar status;
- CSN = 0; // CSN置低,開始傳輸數(shù)據(jù)
- status = SPI_RW(reg); // 選擇寄存器,同時(shí)返回狀態(tài)字
- SPI_RW(value); // 然后寫數(shù)據(jù)到該寄存器
- CSN = 1; // CSN拉高,結(jié)束數(shù)據(jù)傳輸
- return(status); // 返回狀態(tài)寄存器
- }
- uchar SPI_Read(uchar reg)
- {
- uchar reg_val;
- CSN = 0; // CSN置低,開始傳輸數(shù)據(jù)
- SPI_RW(reg); // 選擇寄存器
- reg_val = SPI_RW(0); // 然后從該寄存器讀數(shù)據(jù)
- CSN = 1; // CSN拉高,結(jié)束數(shù)據(jù)傳輸
- return(reg_val); // 返回寄存器數(shù)據(jù)
- }
- uchar SPI_Read_Buf(uchar reg, uchar * pBuf, uchar bytes)
- {
- uchar status, i;
- CSN = 0; // CSN置低,開始傳輸數(shù)據(jù)
- status = SPI_RW(reg); // 選擇寄存器,同時(shí)返回狀態(tài)字
- for(i=0; i<bytes; i++)
- pBuf[i] = SPI_RW(0); // 逐個(gè)字節(jié)從nRF24L01讀出
- CSN = 1; // CSN拉高,結(jié)束數(shù)據(jù)傳輸
- return(status); // 返回狀態(tài)寄存器
- }
- uchar SPI_Write_Buf(uchar reg, uchar * pBuf, uchar bytes)
- {
- uchar status, i;
- CSN = 0; // CSN置低,開始傳輸數(shù)據(jù)
- status = SPI_RW(reg); // 選擇寄存器,同時(shí)返回狀態(tài)字
- for(i=0; i<bytes; i++)
- SPI_RW(pBuf[i]); // 逐個(gè)字節(jié)寫入nRF24L01
- CSN = 1; // CSN拉高,結(jié)束數(shù)據(jù)傳輸
- return(status); // 返回狀態(tài)寄存器
- }
- void RX_Mode(void)
- {
- CE = 0;
- SPI_Write_Buf(WRITE_REG + RX_ADDR_P0, TX_ADDRESS, TX_ADR_WIDTH); // 接收設(shè)備接收通道0使用和發(fā)送設(shè)備相同的發(fā)送地址
- SPI_RW_Reg(WRITE_REG + EN_AA, 0x01); // 使能接收通道0自動(dòng)應(yīng)答
- SPI_RW_Reg(WRITE_REG + EN_RXADDR, 0x01); // 使能接收通道0
- SPI_RW_Reg(WRITE_REG + RF_CH, 40); // 選擇射頻通道0x40
- SPI_RW_Reg(WRITE_REG + RX_PW_P0, TX_PLOAD_WIDTH); // 接收通道0選擇和發(fā)送通道相同有效數(shù)據(jù)寬度
- SPI_RW_Reg(WRITE_REG + RF_SETUP, 0x07); // 數(shù)據(jù)傳輸率1Mbps,發(fā)射功率0dBm,低噪聲放大器增益
- SPI_RW_Reg(WRITE_REG + CONFIG, 0x0f); // CRC使能,16位CRC校驗(yàn),上電,接收模式
- CE = 1; // 拉高CE啟動(dòng)接收設(shè)備
- }
- void TX_Mode(uchar * BUF)
- {
- CE = 0;
- SPI_Write_Buf(WRITE_REG + TX_ADDR, TX_ADDRESS, TX_ADR_WIDTH); // 寫入發(fā)送地址
- SPI_Write_Buf(WRITE_REG + RX_ADDR_P0, TX_ADDRESS, TX_ADR_WIDTH); // 為了應(yīng)答接收設(shè)備,接收通道0地址和發(fā)送地址相同
- SPI_Write_Buf(WR_TX_PLOAD, BUF, TX_PLOAD_WIDTH); // 寫數(shù)據(jù)包到TX FIFO
- SPI_RW_Reg(WRITE_REG + EN_AA, 0x01); // 使能接收通道0自動(dòng)應(yīng)答
- SPI_RW_Reg(WRITE_REG + EN_RXADDR, 0x01); // 使能接收通道0
- SPI_RW_Reg(WRITE_REG + SETUP_RETR, 0x0a); // 自動(dòng)重發(fā)延時(shí)等待250us+86us,自動(dòng)重發(fā)10次
- SPI_RW_Reg(WRITE_REG + RF_CH, 40); // 選擇射頻通道0x40
- SPI_RW_Reg(WRITE_REG + RF_SETUP, 0x07); // 數(shù)據(jù)傳輸率1Mbps,發(fā)射功率0dBm,低噪聲放大器增益
- SPI_RW_Reg(WRITE_REG + CONFIG, 0x0e); // CRC使能,16位CRC校驗(yàn),上電
- CE = 1;
- }
- uchar Check_ACK(bit clear)
- {
- while(IRQ);
- sta = SPI_RW(NOP); // 返回狀態(tài)寄存器
- if(MAX_RT)
- if(clear) // 是否清除TX FIFO,沒有清除在復(fù)位MAX_RT中斷標(biāo)志后重發(fā)
- SPI_RW(FLUSH_TX);
- SPI_RW_Reg(WRITE_REG + STATUS, sta); // 清除TX_DS或MAX_RT中斷標(biāo)志
- IRQ = 1;
- if(TX_DS)
- return(0x00);
- else
- return(0xff);
- }
- unsigned char nRF24L01_RxPacket(unsigned char* RX_BUF)
- {
- unsigned char revale=0;
- //SetRX_Mode();
- sta=SPI_Read(STATUS); // read register STATUS's value
- if(RX_DR) // if receive data ready (RX_DR) interrupt
- {
- CE = 0;
- SPI_Read_Buf(RD_RX_PLOAD,RX_BUF,TX_PLOAD_WIDTH);// read receive payload from RX_FIFO buffer
- revale =1;//we have receive data
- }
- SPI_RW_Reg(WRITE_REG+STATUS,sta);// clear RX_DR or TX_DS or MAX_RT interrupt flag
-
- return revale;
- }
- void main(void)
- {
- uchar a[5]={0xfe,0xfd,0xfc,0xf0,0x1d};
- uchar i;
- init_io(); // 初始化IO
- // RX_Mode(); // 設(shè)置為接收模式
- while(1)
- {
- for(i=0;i<5;i++)
- {
- TX_BUF[i] = a[i]; // 數(shù)據(jù)送到緩存
- TX_Mode(TX_BUF); // 把nRF24L01設(shè)置為發(fā)送模式并發(fā)送數(shù)據(jù)
- Check_ACK(1); // 等待發(fā)送完畢,清除TX FIFO
- delay_ms(250);
- delay_ms(250);
- // RX_Mode();
- }
- }
- }
復(fù)制代碼 |
|