Don't ask why. I can't explain it without violating a Non-Disclosure Agreement.

However, check this out. Search for NMEA Checksum VB.

• http://www.experts-exchange.com/Databases/GIS_GPS/Q_21413235.html
• http://www.codepedia.com/1/Calculating+and+Validating+NMEA+Checksums
• http://www.codepedia.com/1/Taking+Out+the+Garbage:+NMEA+Checksums …

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