Custom Snapmaker U1 Firmware

RFID Filament Tag Support

The Snapmaker U1 automatically detects filament properties by reading RFID tags on spools.

Firmware Support:

• Original: Mifare Classic 1K with Snapmaker proprietary format
• Extended: Adds NTAG215/216 support with OpenSpool format

Supported Formats

🏆 = Recommended for U1 (NTAG215 is the sweet spot for capacity and compatibility)

How It Works

Tags are automatically read when filament is loaded into the feeder. Tag data clears when filament is removed.

Manual Commands:

• Read tag: FILAMENT_DT_UPDATE CHANNEL=<n>
• Clear tag data: FILAMENT_DT_CLEAR CHANNEL=<n>
• Check current tag: FILAMENT_DT_QUERY CHANNEL=<n>

Programming Filament Tags

OpenSpool (Recommended for Extended Firmware)

Quick Setup:

1. Get NTAG215 or NTAG216 tags
2. Open Chrome on Android phone
3. Visit printtag-web.pages.dev
4. Enter filament information
5. Tap tag to phone to write

Alternative: Use any NFC app that supports NDEF with JSON (MIME type: application/json)

Example payload:

{
  "protocol": "openspool",
  "version": "1.0",
  "brand": "Generic",
  "type": "PLA",
  "color_hex": "#FF0000",
  "min_temp": 190,
  "max_temp": 220,
  "bed_min_temp": 50,
  "bed_max_temp": 60
}

Using the non-standard OpenSpool subtype field it is possible to specify a material subtype:

{
  "protocol": "openspool",
  "version": "1.0",
  "type": "PETG",
  "subtype": "Rapid",
  "color_hex": "AFAFAF",
  "additional_color_hexes": ["EEFFEE","FF00FF"],
  "alpha": "FF",
  "brand": "Elegoo",
  "min_temp": "230",
  "max_temp": "260"
}

OpenSpool Field Reference

Required Fields:

• protocol - Must be “openspool”
• version - Specification version (e.g., “1.0”)
• type - Material type (PLA, PETG, ABS, TPU, etc.)
• color_hex - Color in hex format (#RRGGBB)

Optional Standard Fields:

• brand - Manufacturer name
• min_temp / max_temp - Nozzle temperature range in °C

Optional Extended Fields (U1-specific):

• bed_min_temp / bed_max_temp - Bed temperature range in °C
• subtype - Material variant (Basic, Rapid, HF, Silk, etc.)
• alpha - Color transparency (00-FF hex, default: FF)
• additional_color_hexes - Additional colors for multicolor spools (up to 4)
• weight - Spool weight in grams
• diameter - Filament diameter in mm (e.g., 1.75)

Snapmaker Orca Naming Convention

Snapmaker Orca requires filaments to follow this naming pattern: <brand> <type> <subtype>

Examples: Generic PLA Basic, Elegoo PETG Rapid

Reading Existing Tags

Use the NFC Tools app (iOS/Android) to inspect tags:

1. Download NFC Tools from App Store or Google Play
2. Tap “Read” and hold tag to phone
3. Check tag type and NDEF records

Compatible tag types: NTAG213/215/216, Mifare Classic 1K Note: ISO15693 tags (OpenPrintTag) are not supported

Alternative Detection Systems

The OpenRFID detection system is an alternative to Snapmaker’s built-in filament tag detection, based on the OpenRFID project. It adds support for tagged spools from multiple manufacturers.

To enable it, navigate to the firmware-config web interface, go to Snapmaker Components > RFID Detection System, and select OpenRFID or OpenRFID (force generic vendor).

• OpenRFID - Filament is identified by brand and type. Spools unrecognized by Snapmaker Orca are hidden in Snapmaker Orca.
• OpenRFID (force generic vendor) - Same as OpenRFID, but spools are labeled as Generic so they always appear in Snapmaker Orca.
• External - Disables the built-in readers entirely, useful for external readers such as wasikuss/snapmaker-u1-remote-rfid-reader.

Supported Tags

Bambu / Creality Spool Configuration

Bambu and Creality tagged spools require authentication keys. Edit the user configuration file to enable them:

/oem/printer_data/config/extended/openrfid_user.cfg

For Bambu spools:

[bambu_lab_tag_processor]
key = <your 32 hex character key>

For Creality spools:

[creality_tag_processor]
key = <your 32 hex character key>
encryption_key = <your 32 hex character key>

After editing, restart the printer.

Troubleshooting

Tag not detected:

• Ensure tag is NTAG213/215/216 or Mifare Classic 1K
• Position tag within 1-3cm of reader antenna
• Ensure you place on tag on the side next to the U1 housing, which will depend on which side of the printer you load the spool
• If a vendor tag is present, for example Bambu Lab filament tags, this will usually interfere with reading a user-provided tag (you can cover up the vendor tag with foil tape)
• Manually read tag: FILAMENT_DT_UPDATE CHANNEL=<n> then FILAMENT_DT_QUERY CHANNEL=<n>
• Check klippy.log for detection messages

OpenPrintTag tags don’t work:

• Expected - OpenPrintTag uses ISO15693 which is not supported by U1 hardware
• Use NTAG tags with OpenSpool format instead

NTAG tags only work on extended firmware:

• Original firmware only supports Mifare Classic 1K with Snapmaker proprietary format
• Extended firmware adds NTAG215/216 support