simple-nfc-tag

Read and write data to NFC tags — MIFARE Classic, Ultralight and NTAG21x — through PC/SC readers such as the ACR122U, without hand-writing APDUs.

Status: placeholder. 0.0.1 reserves the name and contains no functionality. The design is settled and implementation is underway. Do not depend on this yet.

Why

pyscard gives you raw APDU plumbing. nfcpy drives PN53x chipsets over libusb and fights the PC/SC driver on Windows. ndeflib parses records but never touches hardware. Nothing covers "give me the bytes off this tag, and don't make me care whether it's a Classic or an NTAG."

Planned API

import simple_nfc_tag as snt

with snt.connect() as reader:
    tag = reader.wait_for_tag(timeout=5)
    print(tag.uid.hex(), tag.product, tag.user_size)

    tag.write(["ABC123", 42])   # compact TLV, auto-typed
    print(tag.read())           # -> ["ABC123", 42]

Three access patterns: reader.current_tag() (non-blocking poll), reader.wait_for_tag() (blocking), and Monitor(reader, on_tag=...) (background thread with callbacks).

Planned scope

• Readers — generic PC/SC, ACR122U (buzzer, LED, PN532 passthrough), in-memory fake for tests
• Tags — MIFARE Classic 1K/4K, Ultralight, NTAG213/215/216, identified automatically
• Formats — compact TLV and raw bytes; NDEF planned as a later codec
• Sector-trailer skipping, page-granularity writes and authentication handled for you

License

MIT