nRF24L01介绍

CE：RX或TX模式选择
CSN：SPI片选信号
SCK：SPI时钟
MOSI：SPI数据输入
MISO：SPI数据输出
IRQ：可屏蔽中断脚

51测试程序
实测可用!

#define TX_ADR_WIDTH    5#define RX_ADR_WIDTH    5#define TX_PLOAD_WIDTH  32#define RX_PLOAD_WIDTH  32#define MAX_TX      0x10    //达到最大发送次数中断#define TX_OK       0x20    //TX发送完成中断#define RX_OK       0x40    //接收到数据中断const uchar TX_ADDRESS[TX_ADR_WIDTH]={0xEE,0xDD,0xCC,0xBB,0xAA};    //发送地址const uchar RX_ADDRESS[RX_ADR_WIDTH]={0xAA,0xBB,0xCC,0xDD,0xEE};sbit CE   = P2^7;sbit CSN  = P2^6;sbit MISO = P2^3;sbit MOSI = P2^4;sbit SCK  = P2^5;sbit IRQ  = P2^2;sbit LED=P1^0;void delay_us(uchar num){    uchar i;     for(i=0;i>num;i++)    _nop_();}void delay(uint t){    uchar k;    while(t--)    for(k=0;k<200;k++);}uchar SPI_RW(uchar byte){    uchar bit_ctr;    for(bit_ctr=0;bit_ctr<8;bit_ctr++) // output 8-bit    {        MOSI = (byte & 0x80); // output 'byte', MSB to MOSI        byte = (byte << 1); // shift next bit into MSB..        SCK = 1; // Set SCK high..        byte |= MISO; // capture current MISO bit        SCK = 0; // ..then set SCK low again    }    return(byte); // return read byte}uchar SPI_Write_Reg(uchar reg, uchar value){    uchar status;    CSN = 0; // CSN low, init SPI transaction    status = SPI_RW(reg); // select register    SPI_RW(value); // ..and write value to it..    CSN = 1; // CSN high again    return(status); // return nRF24L01 status byte}uchar SPI_Write_Buf(uchar reg, uchar *pBuf, uchar bytes){    uchar status,byte_ctr;    CSN = 0; // Set CSN low, init SPI tranaction    status = SPI_RW(reg); // Select register to write to    for(byte_ctr=0; byte_ctr<bytes; byte_ctr++) // then write all        SPI_RW(*pBuf++);    CSN = 1; // Set CSN high again    return(status); // return nRF24L01 status byte}void RX_Mode_Init(void){    CE=0;    SPI_Write_Buf(WRITE_REG + TX_ADDR, TX_ADDRESS, TX_ADR_WIDTH);    SPI_Write_Buf(WRITE_REG + RX_ADDR_P0, RX_ADDRESS, RX_ADR_WIDTH);    SPI_Write_Reg(WRITE_REG + EN_AA, 0x01); // Enable Auto.Ack:Pipe0    SPI_Write_Reg(WRITE_REG + EN_RXADDR, 0x01); // Enable Pipe0    SPI_Write_Reg(WRITE_REG + RF_CH, 0);    SPI_Write_Reg(WRITE_REG + RX_PW_P0, TX_PLOAD_WIDTH);    SPI_Write_Reg(WRITE_REG + RF_SETUP, 0x0f);    SPI_Write_Reg(WRITE_REG + CONFIG, 0x0f); // Set PWR_UP bit, enable    CE = 1; // Set CE pin high to enable RX device}uchar SPI_Read_Reg(uchar reg){    uchar reg_val;    CSN = 0; // CSN low, initialize SPI communication    SPI_RW(reg); // Select register to read from..    reg_val = SPI_RW(0); // ..then read registervalue    CSN = 1; // CSN high, terminate SPI communication    return(reg_val); // return register value}uchar NRF24L01_TxPacket(uchar *txbuf){    uchar state;    CE=0;    SPI_Write_Buf(WR_TX_PLOAD,txbuf,TX_PLOAD_WIDTH); //写数据到TX_BUF    CE=1;    while(IRQ==1); //等待发送完成    LED = ~LED;    state=SPI_Read_Reg(STATUS);      SPI_Write_Reg(WRITE_REG+STATUS,state); //清除中断标志TX_DS或MAX_RT    if(state&MAX_TX) //达到最多重发中断    {        SPI_Write_Reg(FLUSH_TX,0xff); //清除TX FIFO寄存器        return MAX_TX;     }    if(state&TX_OK) //发送完成    {        return TX_OK;    }    return 0xff; //发送失败}void Send_Buf(uchar *buf){    CE=0;    SPI_Write_Reg(WRITE_REG+CONFIG,0x0e);    CE=1;    delay_us(15);    NRF24L01_TxPacket(buf);    CE=0;    SPI_Write_Reg(WRITE_REG+CONFIG, 0x0f);    CE=1;   }int main(){    uchar buf[TX_PLOAD_WIDTH];    RX_Mode_Init();    buf[0]=2; //无线串口模块需要第一位标识长度(忽略)    buf[1]=0xaa;    buf[2]=0x55;    while(1)    {        Send_Buf(buf);        delay(1000);    }}

模块不能自发自收

TX_ADDR和RX_ADDR_P0地址可以相同。但是TX_ADDR是目标板地址，RX_ADDR_P0是本模块地址。只有收发地址配置正确才能收发成功

最主要是RX_Mode_Init中寄存器的配置：
RF_CH，射频通道频率。收发必须一致（F0= 2400 + RF_CH [MHz]）
RF_SETUP，射频寄存器。数据传输速率、发射功率、低噪声放大增益，收发必须一致
CRCO，校验方式。收发必须一致