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#1 2017-04-19 18:46:11

Registered: 2017-04-19
Posts: 2

36 bit Wiegand cards

I am trying to figure out the format structure of these cards I tested. I have the internal bits from the card and the printed card number.

Printed: 14315652
Internal: 111011001001101101001110000100001000

Printed: 14315653
internal: 011011001101101101001110000100001010

Printed: 12924846
internal: 011011001011100010100110111101011100

I can see the printed number (24 bits) within the internal and they all have the same 8 bits (11011001) which I figure is the Facility code (217).
The low bit (I consider the low bit to be the right-most bit) is always 0 and the high bit flips like parity. There are also 2 bits that
flip in the middle.
EX: 0 11011001 01 110001010011011110101110 0

Has anybody seen a bit structure like this and how are those 3 flipping bits calculated?

Thanks in advance,


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