ace2k-u1

The Snapmaker U1 side of ace2k, the open firmware that makes the Anycubic ACE 2 Pro a native Klipper MCU. With this adapter, the unit works with the U1's own filament flows:

• load and unload;
• the feed at the start of a print, and the unload at the end;
• runout and tangle detection.

Each of the U1's four heads is fed directly by one lane of the unit.

Status: Release Candidate v0.3.0-rc.1. The long-run print test (burn-in) has not been done yet.

The adapter supports exactly one ACE 2 Pro unit. Lane n feeds head n (extruder n-1): one unit for the printer's four heads. Support for several units is not decided yet (ace2k's roadmap). multiACE already does this today, with the units on their factory firmware.

If you need more than one unit (more than four colours), use multiACE instead. It works well, and many users have tested it. Those units do not run ace2k.

How this was built. AI tools were used in developing this adapter. Every feature and every change was verified on real hardware, over many hours of bench testing, before it was accepted. Human review of the source code is still in progress.

A note on the language. English is not the author's native language, so some terms in this documentation may read a little oddly. Corrections are welcome.

Risks. Flashing third-party firmware onto your ACE 2 Pro carries a small but real risk of damaging it. What limits that risk:

• ace2k never writes to the bootloader or to the unit's factory calibration pages; it only reads them.
• If a flash is interrupted, the unit's bootloader stays in recovery mode. It accepts a new image over the same cable (ace2k's docs/flashing.md).
• The heater runs only with both fans on, and it stops if a temperature sensor fails. The unit's own 115 °C thermal cutout stays in place.

The main remaining risk is the dryer, because it switches mains power. See the warning below.

Disclaimer. This software is provided "as is", without warranty of any kind (see LICENSE). You use it at your own risk. The author is not responsible for any damage to your unit, your printer, your filament or anything else that results from installing or running it. Installing it may void your warranty. This project is not affiliated with or endorsed by Anycubic or Snapmaker.

Tested on. One Anycubic ACE 2 Pro unit on a Snapmaker U1 running the paxx extended firmware 1.6.0-paxx12-22, at 127 V / 60 Hz. Nothing else has been tested.

• klippy/extras/ace2k_u1.py: the [ace2k_u1] section. It attaches at run time to the U1's own side-feeder module (filament_feed), so the U1's flows drive the unit. No file of the printer is replaced.
• klippy/extras/ace2k_u1_tags.py: sets each head's filament setting on the U1 from the spool's tag.
• klippy/extras/ace2k_u1_history.py and web/: the web page http://<printer>/ace2k/.
• config/ace2k-u1.cfg: the adapter's section.

The adapter adds two G-code commands, ACE_EJECT and ACE_ADAPTER_STATUS (docs/commands.md). Everything else is ace2k's own.

Spool tags. A spool from Anycubic, Bambu Lab or Snapmaker carries an RFID tag. The unit reads it while it loads the filament. The adapter then sets that head's filament setting on the U1 from the tag: vendor, type, subtype and colour, as the U1's screen shows them. When the spool leaves the bay, the head goes back to unknown, as the U1 does for any spool. To turn this off, set apply_tags: False in [ace2k_u1]. Loading and feeding are not affected. Details: How a spool's tag sets the head's filament.

These are the three brands ace2k decodes today, but they are not a limit. In principle, any brand works if its tag layout is known (and, for a MIFARE tag, its key or how to derive it). A new brand is added on the host as a small decoder, with no firmware change and no reflash (ace2k's README, "Spool tags from almost any brand").

The U1 keeps its own list of vendors and types. If the U1 does not know a vendor, it shows the name from the tag and uses its generic settings for that type (for example, its generic PLA temperatures).

Open http://<printer>/ace2k/ in a browser on the same network as the U1. <printer> is the U1's address, the same one you use for its own web interface. The page shows:

• the unit's four bays, with their spools' colours;
• each lane's state and actions (load, eject, stop, clear, feed and roll back, read the tag, edit the spool);
• the dryer, with its presets;
• a chart of the chamber's temperature and humidity, and of the heater outlets;
• the unit's events.

The page sends the same G-code commands you can type in the console, and it works on a phone too. Setup and details: The web page. Every action is listed in docs/commands.md.

• A Snapmaker U1 with the paxx extended firmware v1.6.0-paxx12-22.
• ace2k v0.12.0-rc.1, on the unit and on the printer (its host side). Its host interface must be at API_VERSION 6 or later. The adapter does not attach to an older version.
• One ACE 2 Pro unit, with its USB cable plugged into the printer.

• docs/install.md: what the adapter does, how to install it (ace2k first, then the adapter), and how to use it (tags, runout and lane errors, eject, the web page, troubleshooting).
• docs/configuration.md: every setting of ace2k-u1.cfg, with its default and range.
• docs/commands.md: ACE_EJECT, ACE_ADAPTER_STATUS, ACE_CLEAR, the macros of config/ace2k-u1.cfg and the web page.
• ace2k: the firmware and its own documentation.

Built on the published work of hakimio (the ACE 2 Pro protocol) and Simon-CR (the reader protocol and spool-rotation concepts), among others. See ace2k's docs/credits.md. The U1 and its firmware are Snapmaker's; the extended firmware is paxx's.

GPL-3.0 (see LICENSE).