/* ESP32 WiFi Scanning example */
uint8_t A,B = 0;

String resp = "62 48 01 BA 11\r\n";
void setup() {
  Serial.begin(115200);
  delay(500);
  Serial.println(resp);
  getAB(resp);
  Serial.printf("A = %d , B = %d\n",A,B);
  uint16_t  data = (A*256+B)/5/100; //formula 7
  Serial.printf("Formula 7 Data = %d",data);
}

void loop() {
  delay(1);
}

//get A B from response return in global A B variable
void getAB(String elm_rsp) {  //41 05 2A 3C 01>
  if (elm_rsp == "NO DATA\r\r>") {//pid no data
    A = 0;
    B = 0;

  } else {
    //check if pid is 2 or 3 command length.
    uint8_t charcnt = 3;  // 224801
    String strs[8];
    uint8_t StringCount = 0;
    while (elm_rsp.length() > 0) {//keep reading each char
      int index = elm_rsp.indexOf(' ');//check space
      if (index == -1)  // No space found
      { //only data without space is now in strs {41,05,aa,bb}
        strs[StringCount++] = elm_rsp; //last byte
          Serial.println(strs[charcnt].c_str());
          A = strtol(strs[charcnt].c_str(),NULL,16);      //byte 3 save to A
          Serial.println(strs[charcnt+1].c_str());
          B = strtol(strs[charcnt + 1].c_str(),NULL,16);  //byte 4 save to B
        break;
      } else {//found space
        strs[StringCount++] = elm_rsp.substring(0, index);//copy strings from 0 to space to strs
        elm_rsp = elm_rsp.substring(index + 1);//copy the rest behind space to elm_rsp
        
      }
    }  //while
  }    //else
}//getAB