3.溶氧感測器 序列埠監控視窗-MQTT.pdf
#define DO_PIN 36
#define VREF 5000 //VREF (mv)
#define ADC_RES 4096 //ADC Resolution
//Single-point calibration Mode=0
//Two-point calibration Mode=1
#define TWO_POINT_CALIBRATION 0
#define READ_TEMP (25) //Current water temperature ℃, Or temperature sensor function
//Single point calibration needs to be filled CAL1_V and CAL1_T
#define CAL1_V (1600) //mv
#define CAL1_T (25) //℃
//Two-point calibration needs to be filled CAL2_V and CAL2_T
//CAL1 High temperature point, CAL2 Low temperature point
#define CAL2_V (1300) //mv
#define CAL2_T (15) //℃
const uint16_t DO_Table[41] = {
14460, 14220, 13820, 13440, 13090, 12740, 12420, 12110, 11810, 11530,
11260, 11010, 10770, 10530, 10300, 10080, 9860, 9660, 9460, 9270,
9080, 8900, 8730, 8570, 8410, 8250, 8110, 7960, 7820, 7690,
7560, 7430, 7300, 7180, 7070, 6950, 6840, 6730, 6630, 6530, 6410};
uint8_t Temperaturet;
uint16_t ADC_Raw;
uint16_t ADC_Voltage;
uint16_t DO;
int16_t readDO(uint32_t voltage_mv, uint8_t temperature_c)
{
#if TWO_POINT_CALIBRATION == 0
uint16_t V_saturation = (uint32_t)CAL1_V + (uint32_t)35 * temperature_c - (uint32_t)CAL1_T * 35;
return (voltage_mv * DO_Table[temperature_c] / V_saturation);
#else
uint16_t V_saturation = (int16_t)((int8_t)temperature_c - CAL2_T) * ((uint16_t)CAL1_V - CAL2_V) / ((uint8_t)CAL1_T - CAL2_T) + CAL2_V;
return (voltage_mv * DO_Table[temperature_c] / V_saturation);
#endif
}
double DOSensor;
// ---------
#include <WiFi.h>
#include <PubSubClient.h> //請先安裝PubSubClient程式庫
// ------ 以下修改成你自己的WiFi帳號密碼 ------
char* ssid = "YourSSID";
char* password = "YourPassword";
// ------ 以下修改成你MQTT設定 ------
char* MQTTServer = "broker.mqttgo.io";//免註冊MQTT伺服器
int MQTTPort = 1883;//MQTT Port
char* MQTTUser = "";//不須帳密
char* MQTTPassword = "";//不須帳密
//推播主題1:推播溶氧量(記得改Topic)
char* MQTTPubTopic1 = "YourTopic/class402/WaterDO";
long MQTTLastPublishTime;//此變數用來記錄推播時間
long MQTTPublishInterval = 10000;//每10秒推撥一次
WiFiClient WifiClient;
PubSubClient MQTTClient(WifiClient);
void setup() {
Serial.begin(115200);
//開始WiFi連線
WifiConnecte();
//開始MQTT連線
MQTTConnecte();
}
void loop() {
//如果WiFi連線中斷,則重啟WiFi連線
if (WiFi.status() != WL_CONNECTED) { WifiConnecte(); }
//如果MQTT連線中斷,則重啟MQTT連線
if (!MQTTClient.connected()) { MQTTConnecte(); }
//如果距離上次傳輸已經超過10秒,則Publish溶氧量
if ((millis() - MQTTLastPublishTime) >= MQTTPublishInterval ) {
//讀取溫濕度
Temperaturet = (uint8_t)READ_TEMP;
ADC_Raw = analogRead(DO_PIN);
ADC_Voltage = uint32_t(VREF) * ADC_Raw / ADC_RES;
DOSensor = ((double)(readDO(ADC_Voltage, Temperaturet))/1000);
Serial.print("Temperature:\t" + String(Temperaturet) + "\t");
Serial.print("ADC RAW:\t" + String(ADC_Raw) + "\t");
Serial.print("ADC Voltage:\t" + String(ADC_Voltage) + "\t");
Serial.println("DO:\t" + String(readDO(ADC_Voltage, Temperaturet)) + "\t");
Serial.print("目前溶氧:");
Serial.println( String(DOSensor) + " mg/L");
// ------ 將溶氧量送到MQTT主題 ------
MQTTClient.publish(MQTTPubTopic1, String(DOSensor).c_str());
Serial.println("溶氧量已推播到MQTT Broker");
MQTTLastPublishTime = millis(); //更新最後傳輸時間
}
MQTTClient.loop();//更新訂閱狀態
delay(50);
}
//開始WiFi連線
void WifiConnecte() {
//開始WiFi連線
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("WiFi連線成功");
Serial.print("IP Address:");
Serial.println(WiFi.localIP());
}
//開始MQTT連線
void MQTTConnecte() {
MQTTClient.setServer(MQTTServer, MQTTPort);
while (!MQTTClient.connected()) {
//以亂數為ClietID
String MQTTClientid = "esp32-" + String(random(1000000, 9999999));
if (MQTTClient.connect(MQTTClientid.c_str(), MQTTUser, MQTTPassword)) {
//連結成功,顯示「已連線」。
Serial.println("MQTT已連線");
} else {
//若連線不成功,則顯示錯誤訊息,並重新連線
Serial.print("MQTT連線失敗,狀態碼=");
Serial.println(MQTTClient.state());
Serial.println("五秒後重新連線");
delay(5000);
}
}
}