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I maae a dump of a Mifare Classic, NXP, tag.

I can read some information without a problem, but if I write data in a block, I need to terminate the block with a checksum (CRC?, one byte).

I tried with this:

https://hub.zhovner.com/tools/nfc/

http://www.sunshine2k.de/coding/javascript/crc/crc_js.html

But it didn't work.

This are block samples:

000000000000000000000000000000F5

F5000000000000000000000000000000

30000000000000000000000000000096

01E1CCE7090000000000000000000062

So, how determine the last byte (in bold)

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    Given this information, I can only guess that it's likely to be a linear combination of the bits/bytes. I can't see a way to objectively answer the question however. // Try reverse engineer the code used to compute the checksum, if possible. – user202729 Aug 17 '18 at 3:47

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