125KHz RFID Read Only 64bit code question

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Hi there,

I bought some 125KHz RFID tags based on the EM4100 ic (Read Only, 64 bit code). Each card has a unique code printed on the plastic that exists of 10 decimal characters.

A card that I have almost red has this code printed on the plastic: 0010285420. After reading the same tag's 64 bit code the result is:
0x1FF - 9 start bits (always high)
0x06 - 1st row data with row parity bit
0x17 - 2nd row data with row parity bit
0x00 - 3rd row data with row parity bit
0x00 - 4th row data with row parity bit
0x12 - 5th row data with row parity bit
0x18 - 6th row data with row parity bit
0x1E - 7th row data with row parity bit
0x03 - 8th row data with row parity bit
0x0C - 9th row data with row parity bit
0x18 - 10th row data with row parity bit
0x12 - 4 column parity bit and stop bit (always low)

Does somebody knows the relation between the 10 decimal characters printed code and the 64bits code?

Thank you.

Michael.

User of:
IAR Embedded Workbench C/C++ Compiler
Altium Designer

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Your decimal number has 4 zeroes. If there would be
a simple mapping I would expect 4 zeros in the RFIDs data.
But there are onlyy two zeroes. So probably no simple mapping.

My tags have no mnumber upon them. I once had one tag with a
hex number printed, that was exactly found in the RFIDs ID.

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0010285420 converted to binary is 1001 1100 1111 0001 0110 1100

If taken 4 bits at a time, with the parity bit added those match up with rows 5-10 of your list.

0x12 = 10010
0x18 = 11000
0x1E = 11110
0x03 = 00011
0x0C = 01100
0x18 = 11000

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Seraph,

Yes this must be the key.

ossi,

Where do you buy RFID cards. I am planing to make an order to SES RFID (http://www.sesrfid.com/)there in Germany.

Thank you all guys.

Michael.

User of:
IAR Embedded Workbench C/C++ Compiler
Altium Designer

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I bought 2 of these "tag" kits
http://www.watterott.com/de/5-te...

He also have some nice reader modules
http://www.watterott.com/de/125K...
DS: http://www.seeedstudio.com/depot...

/Bingo

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I got my RFIDs from Reichelt. Seems they have only a
German website.

http://such001.reichelt.de/?SID=...

For larger quantities there are probably Suppliers
with better prices.

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Quote:
I bought 2 of these "tag" kits
http://www.watterott.com/de/5-te... ... ID-Tag-Set

I bought a quantity of 100 keyfobs like them in this link's photo, in blue colour and I didn't used them. Actually I will never use them and I want to sell them.

100 x EM4100 blue keyfobs with printed unique code in one side.

Michael.

User of:
IAR Embedded Workbench C/C++ Compiler
Altium Designer