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emsec / ChameleonMini

The ChameleonMini is a versatile contactless smartcard emulator compliant to NFC. The ChameleonMini was developed by https://kasper-oswald.de. The device is available at https://shop.kasper.it. For further information see the Getting Started Page https://rawgit.com/emsec/ChameleonMini/master/Doc/Doxygen/html/_page__getting_started.html or the Wiki tab above.
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Mifare Classic Authentication fails with some readers (RevE) [was: A strange problem] #13

Closed dxls168 closed 8 years ago

dxls168 commented 8 years ago

Hi guys: I made a ChameleonMini recently.When I use a card reader like ACR122 or RC522 to read, it performed well. but when I use a card reader like Mobile phone or access control,it could not pass the second auth. I Found that When I send NT, it did not respond.I think it was I missed the response time.But the first auth with no problem. Looking forward to your reply. dxls

david-oswald commented 8 years ago

This could be a problem with transmission errors due to smaller antennas / "weaker" readers. In RevE, first consider fully removing the "passive power" section ie. the bridge rectifier diodes directly at the antenna.

If you think this is a timing problem, did you compare to an original MFClassic using a scope?

dxls168 commented 8 years ago

hello david: Very grateful for your reply! I tried to get rid of D2 and D4 and R5 but the problem remains the same, I'm finally ready to try XMEA128A4, hoping to improve.Look forward to your new open source products！ dxls

david-oswald commented 8 years ago

This problem should be solved with RevG. If not, please open a new issue.

feifeilanniao commented 8 years ago

My chameleonmini rev_G have the same problem.When i use a Mobile phone to read,Authentication fails

dxls168 commented 8 years ago

I think the problem may have originated from the program. @feifeilanniao

feifeilanniao commented 8 years ago

may be.