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Tag Formats

Technical details on the NFC tag formats supported by SpoolSense.

OpenPrintTag

An open specification for storing filament data on NFC tags using CBOR encoding over NDEF.

  • Spec: openprinttag.org
  • Tag types: ICODE SLIX2 (ISO15693) or NTAG213/215/216 (ISO14443A)
  • Encoding: CBOR in NDEF MIME record (application/vnd.openprinttag)
  • Data: Material type, color, weight, manufacturer, density, diameter, temperatures, brand

SpoolSense implements full read and write support via the openprinttag_lib C library.

TigerTag

A community-driven binary format for NTAG213/215/216 tags.

  • Spec: TigerTag RFID Guide
  • Tag types: NTAG213/215/216 (ISO14443A)
  • Encoding: Fixed 40-byte binary layout starting at page 4
  • Data: Material ID, brand ID, color RGBA, weight, nozzle/bed temps, diameter

Material IDs map to a community-maintained database with ~100 materials.

OpenTag3D

A newer format using CBOR encoding on NTAG tags.

  • Tag types: NTAG215/216 (ISO14443A)
  • Encoding: CBOR
  • Data: Base material, modifiers, manufacturer, color, weight, density, temps

SpoolSense supports full read and write for OpenTag3D via the web UI at /writer/opentag3d.

NFC+

SpoolSense's term for a plain NTAG tag paired with a Spoolman entry. The tag stores only a UID. All spool data (material, color, weight, manufacturer) lives in Spoolman and is linked via the nfc_id extra field.

  • Tag types: NTAG213/215/216 (ISO14443A)
  • Data on tag: None (UID only)
  • Data source: Spoolman database

This is the simplest and cheapest approach. Buy NTAG stickers, register UIDs in Spoolman.

Bambu Lab

MIFARE Classic tags used by Bambu Lab printers. The tag data is encrypted with manufacturer keys.

  • Tag types: MIFARE Classic 1K (ISO14443A)
  • SpoolSense support: UID read only (encrypted data not accessible)
  • SAK: 0x08 (used for auto-detection)