Creating Checksum in PBP

[Tom Gonser]

What I am most interested in is (even if I did a big loop to read all the data into an array) How would I create the checksum?

Seems I'd have to read the data character by character - compute the checksum of the character, then add it to the total until I am done?

sum = var byte ' my checksum handler
NMEA_sum = var byte ' my final checksum
myarray = byte(34)

If I have several variables, why not just read them each in turn:

For i = 1 to (number of characters in myarray)
sum=myarray(i)
- do the checksum routine, which I can't seem to translate to PBP
*** In VB: it looks like this
sum = sum Xor Asc(Mid$(sSentence, i, 1))
Next i

*** My attempt at PBP: looks like this
NMEA_sum = (sum ^(character(i))
Next i

*** then the VB:

NMEA_Checksum = Right$("0" & Hex$(sum), 2)

*** my attempd in PBP: No idea --

NMEA_sum=$sum (?????)

THEN:

NMEA_sum is the answer - a summed up value from all the characters in myarray(i)

Of course this does not work..

Help!