RfidResearchGroup / ChameleonUltra

The new generation chameleon based on NRF52840 makes the performance of card emulation more stable. And gave the chameleon the ability to read, write, and decrypt cards.

https://chameleonultra.com

GNU General Public License v3.0

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fix-LF-emulation #221

Open Dmytro02 opened 3 months ago

Dmytro02 commented 3 months ago

The original EM4100 tag continuously sends its ID. The root problem, in my point of view, was that CU started to "feel" the field too far to be able to modulate it deep enough, and 3 times (LF_125KHZ_BROADCAST_MAX) of repeating takes only about 100ms, CU is still not close enough to the reader. That is why the emulation worked only if the CU moved past the reader quickly (fly by).

github-actions[bot] commented 3 months ago

You are welcome to add an entry to the CHANGELOG.md as well

github-actions[bot] commented 3 months ago

Built artifacts for commit 6145f5c99bc8b986376d10b93a7b4f5e4fb2fe84

Firmware

Client

alexbilevskiy commented 3 months ago

Havent tested it on a real reader yet, but it definitely works with flipper0! So this is a progress, many thanks!

Dmytro02 commented 3 months ago

Havent tested it on a real reader yet, but it definitely works with flipper0! So this is a progress, many thanks!

@alexbilevskiy Thanks a lot, hope it would be useful. Did you have any related problems before?

alexbilevskiy commented 3 months ago

Did you have any related problems before?

LF emulation didn't work at all on my CU

xianglin1998 commented 3 months ago

Has anyone tested and provided more feedback on the test results?

GameTec-live commented 3 months ago

@Dmytro02 in discord REALLY stressed the point that this needs to be reworked in his opinion, so maybe merging as is isnt the best idea?

Dmytro02 commented 3 months ago

It is not. It is just proof of concept. Maybe, if possible, we can rework this part with @doegox (Philippe Teuwen), as I can see he is the main author of this functionality. And together, I believe, we will properly fix the issue.

mitmarcus commented 3 months ago

Did you have any related problems before?

LF emulation didn't work at all on my CU

worked on the bootleg ones

Dmytro02 commented 3 months ago

Did you have any related problems before?

LF emulation didn't work at all on my CU

worked on the bootleg ones

Hello @mitmarcus , could you please add some more details?

mitmarcus commented 3 months ago

By bootleg I meant a chamele0n

Sadly when I purchased, I got this one instead of the original. However, EM4100X worked countless times without problems on at least 3 separate types of readers ¯⁠\⁠⁠(⁠ツ⁠)⁠⁠/⁠¯