New topic: Checksum calculation for NMEA sentence output from GPS
<http://forums.realsoftware.com/viewtopic.php?t=37876> Page 1 of 1 [ 1 post ] Previous topic | Next topic Author Message Talisker Post subject: Checksum calculation for NMEA sentence output from GPSPosted: Sun Feb 27, 2011 9:26 am Joined: Tue Jul 27, 2010 4:27 am Posts: 8 Converted from VB for use with Real Studio. If anyone has a better idea of how to return the two character string, I'd like to hear it! Code:Function Checksum(mySum As String) As String Dim Char(-1) As String, Checksum As Integer, n As Integer, Result As String ReDim Char(Len(mySum)) For n = 0 to Len(mySum) -1 Char(n) = Mid(mySum,n + 1,1) next n for n = 0 to UBound(Char) if Char(n) = "$" then continue if Char(n) = "*" then exit If Checksum = 0 then ' Yes. Set the checksum to the value Checksum = Asc(Char(n)) Else ' No. XOR the checksum with this character's value Checksum = Checksum XOR Asc(Char(n)) End If next n 'add preceding zero if Len(Str(Hex(Checksum))) < 2 then Result = "0" + Str(Hex(Checksum)) else Result = Str(Hex(Checksum)) end if Return Result End Function Steve Top Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending Page 1 of 1 [ 1 post ] -- Over 1500 classes with 29000 functions in one REALbasic plug-in collection. The Monkeybread Software Realbasic Plugin v9.3. http://www.monkeybreadsoftware.de/realbasic/plugins.shtml rbforumnotifier@monkeybreadsoftware.de
