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#1 2013-07-06 06:06:21
- app_o1
- Contributor
- Registered: 2013-06-22
- Posts: 247
What are those extra bits ?
I am "manchester demodulating" some simple tags with some HEX code written on it.
First one "0302584" gives :
0011 0000 0010 0101 0101 1000 0100
= 302584+
Second one "000191" :
0000 0000 0001 1001 0100 1001 0001
= 000191+
What are those 4 more "characters" ? And is there any way to calculate them ?
I don't any other examples so it is a bit hard to understand...
Let's say I have another tag "0782D2", what will be result ?
I am guessing something like "782D2"...
Last edited by app_o1 (2015-06-06 10:14:26)
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#2 2013-07-07 06:16:09
- app_o1
- Contributor
- Registered: 2013-06-22
- Posts: 247
Re: What are those extra bits ?
Looks like this script is to determine the last byte value... So this is not what I need (?)
Last edited by app_o1 (2015-06-06 10:14:43)
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#3 2013-07-07 07:35:28
- app_o1
- Contributor
- Registered: 2013-06-22
- Posts: 247
Re: What are those extra bits ?
Well, that looks much better :
Thanks to henryk !
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#4 2013-07-07 07:39:40
- app_o1
- Contributor
- Registered: 2013-06-22
- Posts: 247
Re: What are those extra bits ?
You then get 32 bits of ID followed by some kind of checksum or parity as a stop sentinel
So what is it exactly ? Checksum, parity, ... ?
Last edited by app_o1 (2015-06-06 10:15:08)
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#5 2013-07-07 12:56:53
- asper
- Contributor
- Registered: 2008-08-24
- Posts: 1,409
Re: What are those extra bits ?
What is "transit.exe" ? Anyway it doesn't seems to be a parity check, it is probably a CRC but I don't know of which type (CRC-8 with specific polynomial value?).
Last edited by asper (2013-07-07 14:15:14)
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