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grich
- 23rd April 2008, 09:24
Does any one have guide routine in PICBasic to calculate CRC16bit MODBUS ?

Thank,
Grich

Kamikaze47
- 26th April 2008, 06:30
A quick forum search found this:

http://www.picbasic.co.uk/forum/showthread.php?t=7646

grich
- 7th May 2008, 09:51
Thanks, and I found list below/
Is this routine right ?


Calcul_CRC16:

CRC16=$FFFF
For i=0 to (DataAmount -3)
CRC16=CRC16^DATACRC[i]
For j=1 to 8
IF CRC16.Bit0=1 Then
CRC16=$A001^(CRC16>>1)
Else
CRC16=CRC16>>1
EndIF
Next j
Next i
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