GPS time parsing

baysidecontrols

Using GPS_IO_mini.spin, I am looking for a method to parse the hours,minutes and seconds from the GPGGA sentence. I can get the time but can not figure out a modification that will allow me to parse out the hours, minutes and seconds separately.

JonnyMac

It's pretty easy to create a routine that extracts a decimal value from a string -- here's one idea:

pub str2dec(pntr, digits) | c

'' extracts decimal value from string

  result := 0                                                   ' clear result

  repeat digits
    c := byte[pntr++]                                           ' get chracter
    if (c => "0") and (c =< "9")
      result *= 10                                              ' prep for digit
      result += (c - "0")                                       ' convert from ASCII
    else
      quit                                                      ' exit if not digit

Just pass the starting address of the section you want and the number of digits. For example, in that program to get hours you should be able to do this:

hrs := str2dec(gps.time, 2)

It appears that the .time() method returns a pointer so you just have to modify that. For minutes you'd do this:

mns := str2dec(gps.time+2, 2)

I've tested the str2dec() method so I know it works, you'll just have to experiment with using it and the GPS object.

baysidecontrols

I knew it would be easy for someone. It worked perfectly the first time. Thanks for the help.

Roger Hummel
Bayside Controls, Inc.