wind.cpp

struct { // WindDirection 監測風向 
    /* 由 23456789 腳, 其中第2腳為正北方
     *  換成角度的話
     *  2 = 0度
     *  3 = 45度
     *  4 = 90度
     *  5 = 135度
     *  6 = 180度
     *  7 = 225度
     *  8 = 270度
     *  9 = 315度
     *  兩者同時亮則為在兩個之間的角度
     */

    const int p[8] = {2,3,4,5,6,7,8,9}; // 測試風向的腳位
    int time_stamp = 0;
    int wind[60]; // 最近一分鐘的紀錄
    int cnt[16]; // cnt[i]: 方向 i 出現的次數
    unsigned long last; // 最後一次更新的時間 

    float wind_dir;

    void init() {
        for (int i = 0; i < 8; i++) {
            pinMode( p[i], INPUT);
        }
        for (int i = 0; i < 8; i++) {
            digitalWrite( p[i], LOW);
        }
    }
    int get_direction() {
        // 回傳 0, ..., 15
        // 回傳 i 表示風向角度為 i * 22.5
        int ret = 0;

        for (int i = 0; i < 8; i++) {
            if (digitalRead( p[i] ) == HIGH) {
                ret = 2 * i;
            }
        }

        for (int i = 0; i < 8; i++) {
            if (digitalRead( p[i] ) == HIGH &&
                digitalRead( p[ (i + 1) % 8 ] ) == HIGH) {
                ret = 2 * i + 1;
            }
        }

        return ret;
    }
    void update_dir() {
        int t = time_stamp % 60;

        if (time_stamp >= 60) cnt[wind[t]]--;
        wind[t] = get_direction();
        cnt[wind[t]]++;

        time_stamp++;
    }
    void most_frequent_dir() {
        int dir = 0;
        for (int i = 0; i < 16; i++) {
            if (cnt[dir] < cnt[i]) {
                dir = i;
            }
        }
        wind_dir = dir * 22.5;
    }
    void do_loop() {
        if ( millis() - last < 1000 ) return; // 每一秒做一次 
        last = millis(); 
        update_dir();
        most_frequent_dir();
    }
} WindDirection;

const int RD_PER_CYCLE = 3; // 幾次算一圈 
struct { // WindSpeed 監測風速
    const unsigned long time_EPS = 100; // 訊號間隔大於 time_EPS ms

    int counter = RD_PER_CYCLE-1;
    unsigned long rot_stamp[RD_PER_CYCLE];
    unsigned long last;

    float rpm;
    float wind_speed;

    void init() {
        pinMode( 10, INPUT);
        digitalWrite( 10, LOW);
    }
    void update_speed() {
        unsigned long t = millis();

        if (digitalRead(10) != HIGH){
            // 如果 10 秒都沒接收到 pin 10 = HIGH 就將 rpm 設成 0
            if ( millis() - last >= 10000 ) rpm = 0.0;
            return;
        }

        if (t - rot_stamp[(counter - 1) % RD_PER_CYCLE] <= time_EPS){
            return;
        }

        unsigned long delta = t - rot_stamp[counter % RD_PER_CYCLE];
        rot_stamp[counter % RD_PER_CYCLE] = t;
        counter++;
        last = t;

        float r = 60.0 * 1000.0 / delta;
        rpm = rpm * 0.9 + r * 0.1;
        wind_speed = 1.0 * rpm;
    }
    void do_loop() {
        update_speed();
    }
} WindSpeed;

#include <SoftwareSerial.h>
SoftwareSerial esp8266(10,11); 
String apiKey = "8QUX6P6Z0CBAI81N";     // ""內輸入ThingSpeak的Write API Key
String ssid = "science1";       // ""內輸入wifi基地台的名稱
String password = "astronomy";   // ""內輸入wifi基地台的密碼
boolean DEBUG = true;
void showResponse(int waitTime){
    long t=millis();
    char c;
    while (t+waitTime>millis()){
      if (esp8266.available()){
        c=esp8266.read();
        if (DEBUG) Serial.print(c);
      }
    }        
}
boolean thingSpeakWrite(float value1, float value2){   //自己增加或減少要上傳的數據項目
  String cmd = "AT+CIPSTART=\"TCP\",\"";
  cmd += "184.106.153.149";
  cmd += "\",80";
  esp8266.println(cmd);
  if (DEBUG) Serial.println(cmd);
  if(esp8266.find("Error")){
    if (DEBUG) Serial.println("AT+CIPSTART error");
    return false;
  }

  String getStr = "GET /update?api_key=";
  getStr += apiKey;

  getStr +="&field1=";
  getStr += String(value1);
  getStr +="&field2=";
  getStr += String(value2);
  // getStr +="&field3=";                             //自己增加或減少要上傳的數據項目
  // getStr += String(value3);
  // ...
  getStr += "\r\n\r\n";

  cmd = "AT+CIPSEND=";
  cmd += String(getStr.length());
  esp8266.println(cmd);
  if (DEBUG)  Serial.println(cmd);
  delay(100);
  esp8266.print(getStr);
  if (DEBUG)  Serial.print(getStr);
  else{
    esp8266.println("AT+CIPCLOSE");
    if (DEBUG)   Serial.println("AT+CIPCLOSE");
    return false;
    }
  return true;
}

void setup() {
    WindDirection.init();
    WindSpeed.init();

    Serial.begin(9600);
    while (!Serial);
    Serial.println("Arduino...OK");

    esp8266.begin(115200);
    esp8266.write("AT+UART_DEF=9600,8,1,0,0\r\n");
    delay(1500);
    esp8266.begin(9600);
    Serial.println("ESP8266...OK");
    esp8266.println("AT+CWMODE=1");   // set esp8266 as client
    showResponse(1000);  
    esp8266.println("AT+CWJAP=\""+ssid+"\",\""+password+"\"");
    showResponse(10000);  //顯示並等待wifi完成連線
}

float& wind_dir = WindDirection.wind_dir;
float& rpm = WindSpeed.rpm;
float& wind_speed = WindSpeed.wind_speed;


void loop() {
    WindDirection.do_loop();
    WindSpeed.do_loop();

    unsigned long time_ms = millis(); //紀錄時間

    Serial.print("Time = ");
    Serial.println(time_ms);
    Serial.print("Direction = ");
    Serial.println(wind_dir, DEC);
    Serial.print("rpm = ");
    Serial.println(rpm, DEC);
    Serial.print("wind_speed = ");
    Serial.println(wind_speed, DEC);

    static unsigned long last_upload_time = 0;
    if ( last_upload_time - millis() >= 20000 ) { // 秒才做一次 
        last_upload_time = millis();
        thingSpeakWrite(wind_dir, rpm);     //自己增加或減少要上傳的數據項目
    }
}