Allow NMEA 0183 file input/output

[PaddyB]

I don't suppose you could share your Arduino code? At least I wouldn't have to start from scratch!

Here are the 2 arduino functions which did the work..

String parseNmea(String nmeaBad)
{
  //Serial.print(nmeaBad);
  nmeaGood=nmeaBad.substring(1, nmeaBad.indexOf("*"));     //cut of the leading "$" and the bad checksum

int  CheckSum=(checkSum(nmeaGood));                //create a good checksum
  nmeaGood="$"+nmeaGood+ "*" +  String(CheckSum, HEX) + "\r\n";     // make the good nmea string

//  Serial.println(nmeaGood); 
return nmeaGood;
}


//---create a nmea checksum
char checkSum(String theseChars) {
  char check = 0;
  // iterate over the string, XOR each byte with the total sum:
  for (int c = 0; c < theseChars.length(); c++) {
    check = char(check ^ theseChars.charAt©);
  } 
  // return the result
  return check;

I was actually just having a look at node-red function but couldn't get it to work, javascript makes my head hurt :
Still failing at sending an nmea sentence to kplex from node red as well. Oh well. :