/* Match Patterns from the I-Bus/K-Bus for the MFSW Button Pushes Version 2
*/

/* Licensed for FREE use under Creative Commons Attribution-Noncommercial 3.0 United States License.

/*
 main serial Rx pin switched via NPN transistor, this pin is connected to the base of the transistor
 serial Rx port is effectively blocked until activateSerialPin is set to high
 serial data from IBUS interface will keep Arduino from fully starting up otherwise
*/
#define activateSerialPin 2
#define CTSSerialPin 3

#define ipodKeyPress 50    // hold the ipod control button for this many msec
#define fwdipodPin 10
#define playipodPin 11
#define revipodPin 12

#define radarKeyPress 100
#define radarmutePin 13

// Extra Pin Definitions - not hooked up to hardware but can be assigned as needed
#define freeKeyPress 0
#define freePin4  4
#define freePin5  5
#define freePin6  6
#define freePin7  7
#define freePin8  8
#define freePin9  9

void setup() {
  pinMode(activateSerialPin, OUTPUT);

  pinMode(fwdipodPin, OUTPUT);
  pinMode(playipodPin, OUTPUT);
  pinMode(revipodPin, OUTPUT);

  pinMode(radarmutePin, OUTPUT);

  //start recieving Serial Data
  Serial.begin(9600);
  digitalWrite(activateSerialPin, HIGH);  
}

void loop() {  
 char incomingByte, checkSum;
 
 // Process data only when you have some data in the buffer to work with
 if (Serial.available() > 0) {
   // read the incoming byte:   
   incomingByte = Serial.read();
   
/* Check if the incoming byte fits our desired patterns
 <Source> <Count> <Dest> <D2> <D3> ... <Dcount> <Xor checksum>
*/
   if (incomingByte == 80) {                            // First byte is a match for a Steering Wheel Button Push event
     do { } while (Serial.available() == 0);            // Make sure there is some data in the buffer
     incomingByte = Serial.read();                      // Grab the next byte
     // Looking for a message with 4 or 3 bytes
     if((incomingByte == 4) || (incomingByte == 3)) {
       do { } while (Serial.available() == 0);          // Get more data and calculate our own checSum = <Dest> + <D2> - <D3>
       checkSum = Serial.read();
       do { } while (Serial.available() == 0);
       checkSum += Serial.read();
       do { } while (Serial.available() == 0);
       checkSum -= Serial.read();
            
       switch (checkSum) {
         case 137:
           // Vol Up
           digitalWrite(freePin4, HIGH);
           delay(freeKeyPress);
           digitalWrite(freePin4, LOW);
           break;
           
         case 138:
           // Vol Down
           digitalWrite(freePin5, HIGH);
           delay(freeKeyPress);
           digitalWrite(freePin5, LOW);
           break;

         case 162:
           // Rt Down
           digitalWrite(fwdipodPin, HIGH);
           delay(ipodKeyPress);
           digitalWrite(fwdipodPin, LOW);
           break;
         case 130:
           // Rt Up
           break;
         case 146:
           // Rt Hold           
           digitalWrite(freePin6, HIGH);
           delay(freeKeyPress);
           digitalWrite(freePin6, LOW);
           break;

         case 155:
           // Lt Down
           digitalWrite(revipodPin, HIGH);
           delay(ipodKeyPress);
           digitalWrite(revipodPin, LOW);
           break;
         case 123:
           // Lt Up
           break;
         case 139:
           // Lt Hold
           digitalWrite(freePin7, HIGH);
           delay(freeKeyPress);
           digitalWrite(freePin7, LOW);
           break;

         case 131:
           // Tel Down
           digitalWrite(freePin8, HIGH);
           delay(freeKeyPress);
           digitalWrite(freePin8, LOW);
           break;
         case 99:
           // Tel Up
           digitalWrite(freePin9, HIGH);
           delay(freeKeyPress);
           digitalWrite(freePin9, LOW);
           break;
         case 115:
           // Tel Hold
           digitalWrite(playipodPin, HIGH);
           delay(ipodKeyPress);
           digitalWrite(playipodPin, LOW);
           break;

         case 47:
           // R/T
           digitalWrite(radarmutePin, HIGH);
           delay(radarKeyPress);
           digitalWrite(radarmutePin, LOW);
         break;
       }       
     }
   }
 }
} //end loop