PM3 Io Prox Simulation

Came across a T5577 card today, with an IO Prox ID on it, I figured I’d give it a go trying to copy and simulate it with the PM3, but quickly got out of my depth, any help would be appreciated:

I got a T5577 dump of the tag, but I don’t have any idea what the io sim command is asking for, can anyone clarify these:
–vn 8bit version
–fc 8bit facility code
–cn 16bit card number

How might I go about figuring these things out? Can I pull this information from the dump?


do lf search it will show you the layout of ioprox cards

edit; let’s live debug this :slight_smile:

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A little more info:


  "Created": "proxmark3",
  "FileType": "t55x7",
  "Card": {
    "ConfigBlock": "80000000"
  "blocks": {
    "0": "80000000",
    "1": "80000000",
    "2": "80000000",
    "3": "80000000",
    "4": "80000000",
    "5": "80000000",
    "6": "80000000",
    "7": "80000000",
    "8": "80000000",
    "9": "80000000",
    "10": "80000000",
    "11": "80000000"

Unfortunately I don’t have the tag with me anymore, I was at an event today doing a bit of a PM3 demonstration for some friends. Now I’m just curious

ok that dump is wrong.

did you do lf t55 detect prior? if no it wouldn’t dump correctly. anyways. commands incoming

lf io sim —vn 01 —fc 186 —cn 26199

vn - version number is just the generation of ioprox chip being used

fc - facility code. all creds in the system share this it tells the system it belongs there. yours is ba so i converted that to decimal so it can be parsed correctly.

cn - unique card number. what identifies you as an individual in the system.

edit: each - is 2 -‘s the formatting is ugly and joins them

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I sure didn’t, I’ve only really played with HF before

I’ll keep that in mind for next time :slight_smile:

I see, I believe I understand how to “decode” that information now, I’ll have to do some playing around

Thank you so much for your help

happy to help. feel free to ping me if you need any more pm3 help or questions. i’m also around on discord @ Equip#1515 i’m in the dangerous things server :slight_smile:

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