Re: How to calculate the checksum?

Christian Havel wrote:
thanks for your help. I have the following informations:

<Sync_1 = 0x81> 8 DATA-BITS No Parity
<Sync_2 = 0x82> 8 DATA-BITS No Parity
<Cksum> = Telegramm<[pos_Sync_1]> XOR . XOR . XOR ... [<pos_Sync_2-2>]
<Cmd> = Command to modem

|<--- CheckSum : --------------- XOR ------------------->|
<Sync_1>, <DEV_ADR>, <Cmd>, <OPTION>, [<DATA>], <Chksum>, <Sync_2>

Hope this helps.

That is not sample data and sample checksum.

It looks more as simple XOR than CRC.

But without more specific information everything will just
be guesswork.

Arne
.

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