cd changer =ELM327+arduino

[vaircom]

Hi all!
I have written simple code that send commands to stereo (jeep) to be able to activate CD changers inputs.

the connection is stereo to ELM327 (pin 2 (J1850)) to Arduino ( pin 7 and8)
its works only if I change if ((strtol(&rxData[0],0,16)==141) to if ((strtol(&rxData[0],0,16)>0)

The plan was: after receiving 8D OF 20 90 replay ATSH8D9301 to stereo/
but seems that I need to polish my code to be able receive 8D 0F 20 90 and then replay 8D 93 01

Code: Select all

#include <SoftwareSerial.h>
SoftwareSerial BTSerial(7, 8); // TX | RX
//char character;
//char DATAFROMMAFON=0;
char rxData[20];
char rxIndex=0;
int led = 13;


void setup()
{
Serial.begin(38400);
BTSerial.begin(38400);

if (BTSerial.available())
Serial.write(BTSerial.read());
if (Serial.available())
//BTSerial.flush();
BTSerial.write(Serial.read());

BTSerial.write("ATL1");
BTSerial.println();
delay (500);
BTSerial.write("ATH1");
BTSerial.println();
delay (500);
BTSerial.write("ATS1");
BTSerial.println();
delay (500);
BTSerial.write("ATAL");
BTSerial.println();
delay (500);
BTSerial.write("ATE0");
BTSerial.println();
delay (500);
Serial.println("ATMA"); //J1850
BTSerial.println();
delay (500);

 if (BTSerial.available() > 0) {
    BTSerial.println("ATSH8D9301");// Hi Im CD changer!
    BTSerial.println();
   delay(50);
    BTSerial.println("0000"); 
    BTSerial.println();
    delay(200);\
    


 }
}


 void loop() {// run over and over
  
  
  BTSerial.flush();

    getResponse();
getResponse();// 


       if ((strtol(&rxData[0],0,16)==141) and (strtol(&rxData[3],0,16)==15)) { 
    digitalWrite(13, HIGH);
    
    BTSerial.println("ATSH8D9301");// 
    BTSerial.println();
   delay(20);
    BTSerial.println("0000"); //п
    BTSerial.println();
    delay(150);


 }
  }
  
  
  
 
   
void getResponse(void){

  char inChar=0;
  {  
    while(inChar != '\r'){
      if(BTSerial.available() > 0){
        if(BTSerial.peek() == '\r'){
          inChar=BTSerial.read();
          rxData[rxIndex]='\0';
          rxIndex=0;
        }
        else {
          inChar = BTSerial.read();
          rxData[rxIndex++]=inChar;
        }
      }
    }
  
  }
  }