nrf24l01与51单片机例子

以下是一个基于 nrf24l01 和 51 单片机的简单示例代码：

#include <reg52.h>
#include "nrf24l01.h"

sbit CE = P1^0;
sbit CSN = P1^1;
sbit SCK = P1^2;
sbit MOSI = P1^3;
sbit MISO = P1^4;

void Delay1ms() {
    unsigned char i, j;
    i = 12;
    j = 169;
    do {
        while (--j);
    } while (--i);
}

void SPI_Init() {
    CE = 0;
    CSN = 1;
    SCK = 0;
    MOSI = 0;
    MISO = 1;
}

void SPI_RW(unsigned char dat) {
    unsigned char i;
    for (i = 0; i < 8; i++) {
        MOSI = (dat & 0x80);
        dat <<= 1;
        SCK = 1;
        dat |= MISO;
        SCK = 0;
    }
}

unsigned char SPI_Read_Reg(unsigned char reg) {
    unsigned char dat;
    CSN = 0;
    SPI_RW(reg);
    dat = SPI_RW(0);
    CSN = 1;
    return dat;
}

void SPI_Write_Reg(unsigned char reg, unsigned char dat) {
    CSN = 0;
    SPI_RW(reg);
    SPI_RW(dat);
    CSN = 1;
}

void NRF24L01_Init() {
    SPI_Init();
    SPI_Write_Reg(WRITE_REG + EN_AA, 0x01);
    SPI_Write_Reg(WRITE_REG + EN_RXADDR, 0x01);
    SPI_Write_Reg(WRITE_REG + SETUP_RETR, 0x1a);
    SPI_Write_Reg(WRITE_REG + RF_CH, 40);
    SPI_Write_Reg(WRITE_REG + RF_SETUP, 0x07);
    SPI_Write_Reg(WRITE_REG + RX_PW_P0, 0x01);
    SPI_Write_Reg(WRITE_REG + CONFIG, 0x0f);
}

void NRF24L01_RX_Mode() {
    CE = 0;
    SPI_Write_Reg(WRITE_REG + CONFIG, 0x0f);
    CE = 1;
    Delay1ms();
}

void NRF24L01_TX_Mode() {
    CE = 0;
    SPI_Write_Reg(WRITE_REG + CONFIG, 0x0e);
    CE = 1;
    Delay1ms();
}

void NRF24L01_Send(unsigned char *buf) {
    unsigned char i;
    CE = 0;
    SPI_Write_Reg(WRITE_REG + STATUS, 0x7e);
    SPI_Write_Buf(WR_TX_PLOAD, buf, TX_PLOAD_WIDTH);
    CE = 1;
    Delay1ms();
    while (IRQ);
    SPI_Write_Reg(WRITE_REG + STATUS, 0x7e);
    SPI_Write_Reg(FLUSH_TX, 0xff);
}

unsigned char NRF24L01_Recv(unsigned char *buf) {
    unsigned char status;
    status = SPI_Read_Reg(STATUS);
    SPI_Write_Reg(WRITE_REG + STATUS, status);
    if (status & RX_DR) {
        SPI_Read_Buf(RD_RX_PLOAD, buf, RX_PLOAD_WIDTH);
        SPI_Write_Reg(FLUSH_RX, 0xff);
        return 0;
    }
    return 1;
}

void main() {
    unsigned char buf[TX_PLOAD_WIDTH];
    unsigned char i;
    for (i = 0; i < TX_PLOAD_WIDTH; i++) {
        buf[i] = i;
    }
    NRF24L01_Init();
    while (1) {
        NRF24L01_TX_Mode();
        NRF24L01_Send(buf);
        Delay1ms();
        NRF24L01_RX_Mode();
        while (NRF24L01_Recv(buf));
        Delay1ms();
    }
}

在这个示例代码中，我们使用了 nrf24l01 的 SPI 接口来与 51 单片机进行通信。我们通过设置各种寄存器来配置 nrf24l01，以使其能够在收发模式下正常工作。在主函数中，我们向 nrf24l01 发送一个数据包并等待接收回复。这个示例仅仅是一个简单的演示，你可以根据自己的需求进行修改和扩展。