20 RFID
RFID mode targets 13.56 MHz NFC/RFID tags using the PN532 reader (I²C). It supports common tag families such as MIFARE Classic (1K/4K/Mini), NTAG/Ultralight, and basic FeliCa operations.
| Command | Description |
|---|---|
read |
Polls for a tag and prints UID / ATQA / SAK / Type every ~300 ms (press ENTER to stop) |
write |
Two flows: UID (magic card) or Block/Page data write (prompts for family, index, and hex data) |
clone |
UID clone: read a source tag, then write its UID to a target (requires magic MIFARE card) |
erase |
Wipes user data on the tag (Classic or NTAG/Ultralight) once the tag is detected |
config |
Interactive setup of I²C pins (SDA/SCL) and PN532 initialization |
- Frequency: PN532 operates at 13.56 MHz (NFC).
-
Tag families (ISO14443A unless noted):
- MIFARE Classic (Mini/1K/4K): 16‑byte blocks with sector trailers; read/write requires authentication (Key A/B).
- NTAG/Ultralight: 4‑byte pages; simple read/write but can be lock‑protected.
- FeliCa (ISO18092): basic polling and block read/write paths exist but are limited in this tooling.
- Write UID and Clone require a “magic” Classic card (block‑0 rewritable using the special backdoor). Normal Classic cards cannot change UID.
- Erase on Classic performs per‑block authentication. If keys are not default, you’ll get authentication failed and the erase will stop.
- Original code from Rennan Cockles (https://github.com/rennancockles), adapted for the ESP32 Bus Pirate.
Configure the PN532 (I2C):
- SDA pin
- SCL pin
- After configuration, the PN532 should be detected and initialized.
- If detection fails, check wiring and pins selection on SDA/SCL.
- The PN532 must be in I2C MODE.
config # Configure I²C pins (SDA/SCL) and initialize PN532
read # Show UID/ATQA/SAK/Type every ~300 ms (ENTER to stop)
write # Choose between "UID (magic card)" or "Block/Page data"
clone # Read source → write UID to target (magic Classic only)
erase # Erase user data (auth required on Classic)
