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MrSwan

Contributor

Registered: 2019-02-04

Posts: 2

Unknown Em410x cards?

So far I've determined the cards are EM410x 64bit 32 clock cycle. What I cant determine is what kind of data they store. They are door access keys. They all have a 6 digit number printed on the cards.

The first byte is the same on all cards, probably a customer number. The second byte is different on the newer cards(increased by 1), probably a version number. From there I cant tell what is going on. It appears to be a "sebury pattern"(Can anyone explain this?) but that does not hold true when the number printed on the card is 6 digits instead of 4 or 5.
Any ideas on how this 6 digit number is encoded on the card? Any thoughts on what the 3rd byte may be?

Any help would be greatly appreciated.

12FE8105F6  This is the oldest card. Possibly a version # on the 2nd byte?
Printed on card: 067062
0001 0010 1111 1110 1000 0001 0000 0101 1111 0110
                         0001 0000 0101 1111 0110  <-- Printed number in binary

12FF8018DA  
Printed on card: 006362
0001 0010 1111 1111 1000 0000 0001 1000 1101 1010
                         0000 0001 1000 1101 1010 

12FF80F202 
Printed on card: 061954
0001 0010 1111 1111 1000 0000 1111 0010 0000 0010
	 	         0000 1111 0010 0000 0010  


12FF07AB8D
Printed on card: 436063
0001 0010 1111 1111 0000 0111 1010 1011 1000 1101
		         0110 1010 0111 0101 1111   <-- pattern doesn't hold up here


12FF07E361 
Printed on card: 450355
0001 0010 1111 1111 0000 0111 1110 0011 0110 0001
		         0110 1101 1111 0011 0011  <-- pattern doesn't hold up here

-Swan

Last edited by MrSwan (2019-02-05 10:24:57)

marshmellow

Contributor

From: US

Registered: 2013-06-10

Posts: 2,302

Re: Unknown Em410x cards?

This appears to be a casi rusco card.  Which has a 6 digit prefix (kinda like facility code,) and a 6 digit card #.  With some research and/or testing you should be able to find where the bit math happens for the higher numbers.