Creating Checksum in PBP

[NavMicroSystems]

Tom,

I have dealt with NMEA a few times in the past.

The checksum is optional, and you do not really need it
(as long as your wires aren't too long and the environment isn't too "noisy")

What the example does is pretty simple:

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Num_To_ASCII:
Dec_lat1 = 119
C[7] = Dec_lat1 DIG 2+"0" ' element c[7] = ASCII 1
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DIG2 of Dec_lat1 in this example is decimal 1 (or $01)
the ASCII value for the character "1" is 31, so you need to add 30
(which equals the the decimal value of the ASCII character "0")
to get the ASCII value for this character

You could also use this:
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C[7] = Dec_lat1 DIG 2+30 ' element c[7] = ASCII 1
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(hope it is not too confusing)