#include <SoftwareSerial.h>
SoftwareSerial mySerial(12, 13); //Uno Rx Tx (12 13) = SoftwareSerial
const char* Poll_mode = "M 01\r\n";
const char* O2_Read = "%\r\n";
String str;
void setup() {
  Serial.begin(9600); //시리얼 통신 초기화
  mySerial.begin(9600);
  Serial.println("SST GAS Sensor");
  delay(1000);
  mySerial.print(Poll_mode);
}                              
void loop() 
{
  /* Response 
  ex) O XXX T XXX P XXX % XXX e xxx
      O XXX: PPO2
      T XXX: temperature
      P XXX: barometric pressurec
      % XXX: O2
      e XXX: Sensor Status
  */
  mySerial.print(O2_Read);
  delay(1000);
   if(mySerial.available()>0) 
   { 
    str = "";
    str = mySerial.readStringUntil('\n'); 
    Serial.println(str);
   }
}