esp8266 AT명령어로 GET으로 request하는 예제

#include <SoftwareSerial.h> #define ssid "ssid" #define password "password" SoftwareSerial espSerial(10, 11); int cmdSize = 0; long previousMillis = 0; void setup(void) {   Serial.begin(9600);   espSerial.begin(9600);   connectWifi(); }   void loop(void) {   long currentMillis = millis();   if(currentMillis - previousMillis >= 7000)   {     previousMillis = currentMillis;     requestBusInfo();   }   if(espSerial.available())   {     Serial.write(espSerial.read());   } } void connectWifi() {   espSerial.println("AT+CWMODE=1");   while(espSerial.available()){     Serial.write(espSerial.read());   }   delay(500);   espSerial.println("AT+CIPMUX=0");   while(espSerial.available()){     Serial.write(espSerial.read());   }   delay(500);   espSerial.print("AT+CWJAP=\"");   espSerial.print(ssid);   espSerial.print("\",\"");   espSerial.print(password);   espSerial.println("\"");   while(espSerial.available()){     Serial.write(espSerial.read());   } } void requestBusInfo(){   cmdSize = strlen("GET /ws/rest/busarrivalservice?serviceKey=1234567890&routeId=207000004&stationId=207000125 HTTP/1.1")               + strlen("Host:openapi.gbis.go.kr\r\n\r\n") + 2;   espSerial.println("AT+CIPSTART=\"TCP\",\"openapi.gbis.go.kr\",80");   delay(500);   espSerial.print("AT+CIPSEND=");   delay(100);   espSerial.println(cmdSize);   delay(100);   espSerial.println("GET /ws/rest/busarrivalservice?serviceKey=1234567890&routeId=207000004&stationId=207000125 HTTP/1.1");   espSerial.println("Host:openapi.gbis.go.kr\r\n\r\n"); }