nrl24l01 每次只能发送 4 个字节, 前面说到, 第一个字节用于源节点, 第二个字节用于目的节点因此只剩下两个字节用于温度和湿度, 一个字节只有八位, 需要表示温湿度的正负数, 因此每个字节的第一位表示正负符号, 后七位表示数据, 最大能表示 +-127
如下:
- #include < cstdlib > #include < iostream > #include < sstream > #include < string > #include < unistd.h > #include < RF24 / RF24.h > using namespace std;
- // RPi generic:
- RF24 radio(22, 0, BCM2835_SPI_SPEED_8MHZ);
- /********** User Config *********/
- // Assign a unique identifier for this node, 0 or 1
- bool radioNumber = 1;
- bool role = 0; //receive mode
- unsigned long start_time = millis();
- unsigned long count = 0;
- /********************************/
- // Radio pipe addresses for the 2 nodes to communicate.
- const uint64_t pipes = 0xE8E8F0F0E1LL;
- unsigned long receData;
- unsigned long respData = 0x01;
- unsigned long srchead = 0x00000000;
- int main(int argc, char * *argv) {
- // cout << "RF24/examples/GettingStarted/\n";
- // Setup and configure rf radio
- radio.begin();
- // optionally, increase the delay between retries & # of retries
- radio.setRetries(15, 15);
- // Dump the configuration of the rf unit for debugging
- //radio.printDetails();
- radio.openReadingPipe(1, pipes);
- /***********************************/
- // This simple sketch opens two pipes for these two nodes to communicate
- // back and forth.
- radio.startListening();
- //cout << "Listening .... \n";
- int node = atoi(argv[1]);
- //cout << "Listening Node is :" <<node<<"\n";
- while (1) {
- unsigned long end_time = millis();
- if (radio.available()) {
- radio.read( & receData, sizeof(unsigned long));
- //cout<<"receData is:"<<receData<<"\n";
- unsigned int check = (unsigned int) receData >> 24;
- unsigned long data = receData & 0x0000ffff;
- //cout<<"check is"<<check<<"\n";
- if (check == node && (receData & 0x00ff0000) == srchead) {
- //cout<<"Get Node oriData:"<<receData<<",data:"<<data<<",Time consume"<<(end_time-start_time)<<"ms \n";
- int temperature = (data & 0x00007f00) >> 8;
- int humidity = data & 0x0000007f;
- if ((0x00008000 & data) == 0) {
- temperature = -temperature;
- }
- if ((0x00000080 & data) == 0) {
- humidity = -humidity;
- }
- cout << temperature << "-" << humidity << "\n"; // 温度 - 湿度
- break;
- }
- }
- //cout<<"time out is"<<(end_time-start_time)<<"\n";
- if ((end_time - start_time) >= 5000) {
- cout << "Wait Data from Node" << node << "time out \n";
- break;
- }
- }
- return 0;
- }
Arduino Leonardo 代码
如下:
- #include < SPI.h > #include "RF24.h"#include < SPI.h > #include "RF24.h"#include < printf.h > #include < dht.h > dht DHT;#define DHT22_PIN 7
- /****************** User Config ***************************/
- /*** Set this radio as radio number 0 or 1 ***/
- bool radioNumber = 0;
- /* Hardware configuration: Set up nRF24L01 radio on SPI bus plus pins 7 & 8 */
- RF24 radio(9, 10);
- /**********************************************************/
- byte addresses[][6] = {
- "1Node",
- "2Node"
- };
- // Used to control whether this node is sending or receiving
- bool role = 1; //1 表示发送模式, 0 表示接收模式
- unsigned long start_time = millis();
- // 这个是我们即将建立的传输渠道编码
- //!! 要和另一个模块的一致
- const uint64_t pipes = 0xE8E8F0F0E1LL;
- // 这个变量会保持我们接受到的信息
- // 变量类型一定要和传过来的一样
- // 要传输的数据
- unsigned long sendData = 15;
- unsigned long srchead = 0x01; // 高 16 位为头标志, 前 8 位为源节点, 后 8 位为目的节点根据标志不同区分不同发送源, 00 为中心主节点
- unsigned long deshead = 0x00; // 高 16 位为头标志, 前 8 位为源节点, 后 8 位为目的节点根据标志不同区分不同发送源, 00 为中心主节点
- unsigned long receData;
- void setup() {
- pinMode(13, OUTPUT); // 指示灯
- Serial.begin(57600);
- printf_begin();
- Serial.println(F("RF24/examples/GettingStarted"));
- radio.begin();
- radio.setPALevel(RF24_PA_MAX);
- radio.openWritingPipe(pipes);
- }
- void loop() {
- // Serial.print("role:");
- // Serial.println(role);
- if (role) {
- int chk = DHT.read22(DHT22_PIN); // 读取数据
- if (chk == DHTLIB_OK) {
- int humidity = (int)(DHT.humidity + 0.5);
- int temperature = (int)(DHT.temperature + 0.5);
- Serial.print("data:temperature=");
- Serial.print(temperature);
- Serial.print(",humidity=");
- Serial.println(humidity);
- // 第三个字节存放温度, 第四个字节存放湿度, 目前只能表示
- unsigned long data = (temperature << 8) + (humidity) + (srchead << 24) + (deshead << 16);
- if (temperature > 0) {
- data = data + 0x00008000;
- }
- if (humidity > 0) {
- data = data + 0x00000080;
- }
- Serial.print("Sending:");
- Serial.println(data);
- digitalWrite(13, HIGH);
- bool ok = radio.write( & data, sizeof(unsigned long));
- role = 0;
- radio.openReadingPipe(1, pipes);
- radio.startListening();
- start_time = millis();
- }
- }
- if (!role) {
- digitalWrite(13, LOW);
- if (radio.available()) {
- radio.read( & receData, sizeof(unsigned long));
- // 根据目标节点, 判断是否是发给自己的, 如果是, 执行相关操作
- unsigned long check = (receData & 0x00ff0000) >> 16;
- if (check == srchead) {
- // 接收到来自主机的数据, 执行相关操作
- Serial.print("Response:");
- Serial.println(receData & 0x0000ffff);
- Serial.println("=======================");
- sendData++;
- }
- role = 1;
- radio.stopListening();
- } else {
- unsigned long end_time = millis();
- if ((end_time - start_time) >= 100) {
- role = 1;
- radio.stopListening();
- radio.openWritingPipe(pipes);
- }
- }
- }
- } // Loop
来源: http://www.bubuko.com/infodetail-2495754.html