Example

IoT Thinkspeak

01 Mar 2021

系統方塊圖

humidity

temperature

code

#include #include "DHT.h"

#define DHTPIN 19 // NodeMCU pin D6 connected to DHT11 pin Data DHT dht(DHTPIN, DHT11, 15);

const char* ssid = “x”; const char* password = “000000005”;

const char* host = “api.thingspeak.com”; const char* thingspeak_key = “7Z2GSN3HKGY0M6BB”;

void turnOff(int pin) { pinMode(pin, OUTPUT); digitalWrite(pin, 1); }

void setup() { Serial.begin(115200);

// disable all output to save power turnOff(0); turnOff(2); turnOff(4); turnOff(5); turnOff(12); turnOff(13); turnOff(14); turnOff(15);

dht.begin(); delay(10);

// We start by connecting to a WiFi network

Serial.println(); Serial.println(); Serial.print(“Connecting to “); Serial.println(ssid);

WiFi.begin(ssid, password);

while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print(“.”); }

Serial.println(“”); Serial.println(“WiFi connected”);
Serial.println(“IP address: “); Serial.println(WiFi.localIP()); }

int value = 0;

void loop() { delay(5000); ++value;

Serial.print(“connecting to “); Serial.println(host);

// Use WiFiClient class to create TCP connections WiFiClient client; const int httpPort = 80; if (!client.connect(host, httpPort)) { Serial.println(“connection failed”); return; }

String temp = String(dht.readTemperature()); String humidity = String(dht.readHumidity()); //String voltage = String(system_get_free_heap_size()); String url = “/update?key=”; url += thingspeak_key; url += “&field1=”; url += temp; url += “&field2=”; url += humidity;

Serial.print(“Requesting URL: “); Serial.println(url);

// This will send the request to the server client.print(String(“GET “) + url + “ HTTP/1.1\r\n” + “Host: “ + host + “\r\n” + “Connection: close\r\n\r\n”); delay(10);

// Read all the lines of the reply from server and print them to Serial while(client.available()){ String line = client.readStringUntil(‘\r’); Serial.print(line); }

Serial.println(); Serial.println(“closing connection. going to sleep…”); delay(1000); // go to deepsleep for 1 minutes //system_deep_sleep_set_option(0); //system_deep_sleep(1 * 60 * 1000000); delay(1601000); }

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