[plug] OT: Data check digits

[Shayne O'Neill]

My take too.... (No idea what the data represents here. What *IS* the
context of these comms)

> Assuming this, 0>1: \x06 seems to be an ack. of sorts
> 0>1: \x05
>     (start download)

Or some sort of handshake "Ready to send" or something.

> 1>0: \x06
>     (ack)
> 0>1: \x01BHTQTYS.DAT 00003051304080808\x035

Ok. Your first byte here seems to be the key part here.
01 = file name or header packet
05 = start of comms
02 = line of data
04 = end of data.
Wonder what 03 is?

is that a space or a null after the file name?

Also is that terminator 035 or 03 then 05.

The 03 then 05 would match the data lines (\02)


>     (data)
> 1>0: \x06
>     (ack)
> 0>1: \x020000193117420003800005                        \x03\x07
>     (data)

after the \02 and before the \03 is this

00 00 19 31 17 42 00 03 80 00 05

Have I got the base right. Is this one big number or a string or what?

it seems its only the final byte thats the mystery here.

Hmm added together 197 .. thats not it.
added in hex 12b ..not it either
Its not octal, cos theres 8's and nines
single bytes 44 (2c hex) .. no.
bytes in decimal xor-ed = 97. no
bytes in hex xor-ed = FB. no

Dude. That final byte has me stumped

Can we get a data dump in straight hex dump format

00 b4 2e 00 0a  etc
broken up by packet like you have here.....

Is it possible at all that that final byte is either a pointer or a status
byte?

I used to reverse engineer serial stuff for a living... enjoy the
chalange.


> 1>0: \x06
>     (ack)
> 0>1: \x0200002742709112010 0003                        \x03\x1e
>     (data)
> 1>0: \x06
>     (ack)
> 0>1: \x0200003637407193402 0015                        \x03\x18
>     (data)
> 1>0: \x06
>     (ack)
> 0>1: \x04
>     (End of Data)
> 1>0: \x06
>     (ack).
>
>   But then again, I could be WAY off.
>
> cheers
>
> Paul
>
>
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