Duet 3 firmware configuration limitations
RepRapFirmware (as at version 3.3.1) for Duet 3 currently has the following limitations when tool boards or expansion boards are used.
Permanent limitations
We do not intend to remove these in future firmware versions.
- After upgrading firmware on an expansion or tool board, its configuration settings are lost. You must restart the main board, or at least re-run config.g. Duet Web Control usually restarts the main board automatically after auto-installing firmware on an expansion or tool board..
- A heater on an expansion or tool board can only be controlled by a temperature sensor on the same expansion board. This is a safety precaution.
- Filament monitors must be connected to the same board as the corresponding extruder motor.
Semi-permanent limitations
We have no plans to remove the following limitations, although removing them would be technically possible.
- A thermostatically-controlled fan on an expansion board can only be controlled by a temperature sensor on the same expansion board.
- Z probes connected to expansion or tool boards are limited to types 8 and 9.
- DHT temperature/humidity sensors connected to expansion boards are not supported
Temporary limitations
We plan to remove these in future firmware releases.
- Filament monitors for extruders driven by expansion boards and tool boards are not yet supported. Support is planned in release 3.2.0.
- Heater tuning is not yet supported on expansion or tool boards (M303). Support is planned in release 3.3.0. For now, use the manual turning procedure instead.
- Endstop switches and Z probes connected to the main board cannot control motors on an expansion board. This is planned to be fixed in release 3.3.0.
- If you use a Z probe then the Z motors must be connected to the main board. This is planned to be fixed in release 3.3.0.
- Stalls of expansion board motors are not yet reported and cannot be used for homing
- Overheat warnings from stepper drivers on expansion boards are not proactively reported (but can be queried using M122)
- Software reset data is not available for expansion boards. This is planned for release 3.2.0.
6 Comments
Raspberry Pi has great support for DHT. There may be, at most, 500ms delay vs. Duet-driven control, but that would not functionally matter. Simply use what the RPi has, and send the relevant commands. Let me know if this doesn’t make sense; super simple script.
The Beach Today - Reply
There are a couple of additional things related to expansion boards that I’m aware of. As of today (31st October) M581 on expansion boards is not yet implemented, and neither is M303 heater tuning . Also, thermostatic fans on expansion boards will randomly “blip”. Not a big issue but I suggest users keep fingers clear of such fans until this gets fixed.
Ian Pegg - Reply
looking for help connecting and configuring a vfd to the duet3
jason lipavsky - Reply
if you have a Duet 3 rev 1.0 main board, there is an output marked LASER/VFD. Use it to provide the input to a PWM to 0-10V converter.
David Crocker -
how do i define it to that output?
jason lipavsky - Reply