What kind of button is this?

iButton 1-Wire
#1

Hi there,

I have this key that I try to read with my flipper, it says CRC error (08 B9 C4…), I have no clue what it is and I cannot find any datasheet.
image

When I try to emulate the key on the device
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It is complaining about an unreadable key.
Clearly security through obscurity, so if anyone can point me what to look for, I would be very grateful.

Thank you very much!

#2

My best guess is a timing issue makes it unreadable. That would explain the CRC check fail. CRC verifies you read a valid key. I’m no I-button guru though.

This has a lot of technical info assuming I got the correct manual.

#3

Thanks for your answer. However, it is not the correct device, it has nothing to do with the microprocessor :/.
Bad CRC can also be if they do not comply with the 1-wire protocol.

#4

My guess it’s simply that flipper doesn’t know about the type of key that you have … Flipper only know about Dallas that start by 01 not other formats. We need READ RAW for 1-wire so that we can capture non-supported keys to request implementation for those unknown formats.

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#5

Would be great indeed. In the meantime, I will try to get a hand over a logic analyzer, GPIO pin 17 is linked to the 1-wire.
Did someone already open one of these keys? Mine has no number on it, nothing to identify the constructor.

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