so I got a hold of some blank t5577 key fob. They were from Amazon :
YARONGTECH-10 PCS Writable 125kHz RFID Key Fob Proximity ID Card Token Tag Rewritable T5577 Universal
It states the following on amazon page for the FOBs:
Original T5577 Chip,it doesn’t have pre-programmed id number,so need to write the id on it before you read
it’s rewritable chip,and it can write in 125khz id format and H ID WG 125khz format
Please note it can’t be read before you program the chip
Ok… so these are reading just like the other FOB’s I was having issues with. The exact same type of data and the exact same type of issue. So let’s get noobish! WTF does it mean write the ID. Does that mean you have to make the FOB into for instance a em 410x ID? If so, then I should be able to make the FOB into an Prox HID ID yes? Then I could clone my work card. Hmm, well guess what I tried and still it won’t friggin clone! Starting to think something up with the antenna? Not have it tuned properly… I don’t get why these don’t work just a regular T5577 card it should be the same! Frustrated now!
Proxmark3 sitting on my computer desk… nothing around it other than monitor and keyboard. Table is a thick wood table the kind used in college classes in lab’s and that sort of thing.
results of “hw tune”
[usb] pm3 → hw tune
[=] ---------- Reminder ------------------------
[=] hw tune doesn’t actively tune your antennas,
[=] it’s only informative.
[=] Measuring antenna characteristics, please wait…
[-] 9
[=] ---------- LF Antenna ----------
[+] LF antenna: 65.78 V - 125.00 kHz
[+] LF antenna: 33.93 V - 134.83 kHz
[+] LF optimal: 65.78 V - 125.00 kHz
[+] Approx. Q factor (): 10.9 by frequency bandwidth measurement
[+] Approx. Q factor (): 19.1 by peak voltage measurement
[!] Contradicting measures seem to indicate you’re running a PM3_GENERIC firmware on a RDV4
[!] False positives is possible but please check your setup
[+] LF antenna is OK
[=] ---------- HF Antenna ----------
[+] HF antenna: 36.28 V - 13.56 MHz
[+] Approx. Q factor (*): 10.5 by peak voltage measurement
[+] HF antenna is OK
(*) Q factor must be measured without tag on the antenna
[+] Displaying LF tuning graph. Divisor 88 (blue) is 134.83 kHz, 95 (red) is 125.00 kHz.
first i found out my antenna was not set on the back to the correct voltage. I also found out that some of the FOBs were password protected (which was my fault) I had used these as test subjects trying to learn. Did not realize I put password on them I was able to remove password and get them working. I however do still have a few FOB’s that I did not password them and for the life of me cannot get the lf t55xx detect command to work. They just refuse to show me their chipset. Anyways… for now i got accomplished what I needed… soo going to give it a rest for a day or two… then I will resume to find out why these few FOB’s just refuse to respond.
Sorry, I didn’t realise that you are using a a Proxmark3 RDV4.
In that case you also have a firmware mismatch (you can change the platform in Makefile.platform to PM3RDV4).
As for the cards that don’t show up, I discovered that a blank T55XX does not respond to lf t5 info so you might want to write a tag to them first and try again.
I did this once b4 … and when i finished installing and flashing… the loaded it told me I had a hardware firmware mismatch. When i install and flash with pm4generic i don’t get that error and I know I have a proxmark3RDV4 because i bought from https://hackerwarehouse.com/
sorry not they are not High Frequency fobs… but to answer your questions I have done lf search and they respond as if they are emulating a em410x however I cannot actually access the FOB because I need to be able to lf t55xx detect to them first in order to send commands. At least this is my understanding
No, you can send commands anyway. But if they are currently claiming to be an em401x and are not responding to lf t5 info then they might well be an em401x.
You could also try just writing a new id and seeing if that takes.
depending on your firmware version, something like ( co firm syntax with your proxmark)
By the way, if you really want to make sure you never forget your pass you might want to consider a Flex Em or a XEm both of which are implantable T5577 chips, the difference is in the packaging. The XEm would be easier to install, but the FlexEm should have better connectivity.