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OK NODE=1 TAG=41003D948F67

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OK NODE=2 LIGHT=208 MOTION=1 DOOR=0 MAILBOX=0 HUM=53 TEMP=233 BAT=0

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OK NODE=1 TAG=41003D948F67

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#include "NewSoftSerial.h"
#define stx 2
#define etx 3

NewSoftSerial mySerial(6, 7);
int counter;
byte data[14];
byte hexBlock1,hexBlock2,hexBlock3,hexBlock4,hexBlock5;
byte hexCalculatedChecksum,hexChecksum;

void setup() {
  Serial.begin(9600);
  mySerial.begin(9600);
}

void loop() {
  if (mySerial.available() > 0) {
    data[counter] = mySerial.read();
    //Serial.println(data[counter],DEC);
    counter++;
    if(counter > 13) {
      //we read the whole message, so reset counter
      counter = 0;
      //check if start of text and end of text is correct
      if(data[0] == stx && data[13] == etx) {
        Serial.println("Start of text and end of text correctly received.");
        Serial.print("ID: ");
        //show ID
        for(int x = 1; x < 11; x++) {
          Serial.print(data[x], BYTE);
        }
        Serial.println("");
        Serial.print("Checksum: ");
        //show checksum
        Serial.print(data[11], BYTE);
        Serial.println(data[12], BYTE);

        //Hex ID blocks. Two transmitted Bytes form one Hex ID block.
        //Hex ID blocks:      6   2  |  E   3  |  0   8  |  6   C  |  E   D
        //Transmitted Bytes: 36H 32H | 45H 33H | 30H 38H | 36H 43H | 45H 44H
        hexBlock1 = AsciiCharToNum(data[1])*16 + AsciiCharToNum(data[2]);
        hexBlock2 = AsciiCharToNum(data[3])*16 + AsciiCharToNum(data[4]);
        hexBlock3 = AsciiCharToNum(data[5])*16 + AsciiCharToNum(data[6]);
        hexBlock4 = AsciiCharToNum(data[7])*16 + AsciiCharToNum(data[8]);
        hexBlock5 = AsciiCharToNum(data[9])*16 + AsciiCharToNum(data[10]);
        
        //Transmitted checksum.
        hexChecksum = AsciiCharToNum(data[11])*16 + AsciiCharToNum(data[12]);

        //XOR algorithm to calculate checksum of ID blocks.
        hexCalculatedChecksum = hexBlock1 ^ hexBlock2 ^ hexBlock3 ^ hexBlock4 ^ hexBlock5;
        if ( hexCalculatedChecksum == hexChecksum )
        {
          Serial.println("Calculated checksum matched transmitted checksum.");
        } 
        else {
          Serial.println("Calculated checksum didn't match transmitted checksum. Corrupt data!");
        }
      }
    } 
  }
}

uint8_t AsciiCharToNum(byte data) {
  //First substract 48 to convert the char representation
  //of a number to an actual number.
  data -= '0';
  //If it is greater than 9, we have a Hex character A-F.
  //Substract 7 to get the numeral representation.
  if (data > 9) 
    data -= 7;
  return data;
}