A custom minimal version of Duet 1LC?

zapta

This questions is for @dc42 and @T3P3Tony but feedback from others will also be appreciated.

I am considering creating a stripped down version of 1LC that contains only the accelerometer and nothing else. Before I get into more detailed questions, is this approach feasible? Is it compatible/encouraged by Duet3d's open source policy?

Things I hope to achieve:

Full compatibility with Duet's tool-board binaries (I don't want to create my own firmwares)
Full compatibility with duet's main boards (e.g. Mini5+).
Small footprint.
Can be used as an open source base line for other custom boards (e.g. a Voron specific tool board).

https://github.com/Duet3D/Duet3-Toolboard-1LC/blob/master/ToolBoard_1LC_v1.1/Duet3_TB_1LC_Schematic_v1.1.pdf

o_lampe

@zapta Some people had problems with wiring their accelerometer boards. Especially long range is problematic. With that in mind, a SammyC21 based accelerometer would be nice to have.
But is it worth it? We might need it only for a short afternoon, dialing in the Input shaper frequence and then it ends in the might be useful later- drawer.

T3P3Tony

@zapta if you use the same pin assignments but leave the unused pins disconnected, then the firmware should be compatible.

dc42

@o_lampe said in A custom minimal version of Duet 1LC?:

@zapta Some people had problems with wiring their accelerometer boards. Especially long range is problematic. With that in mind, a SammyC21 based accelerometer would be nice to have.
But is it worth it? We might need it only for a short afternoon, dialing in the Input shaper frequence and then it ends in the might be useful later- drawer.

You might find another use for the SAMMYC21 later on.

I test SPI accelerometer support using a 1m long accelerometer ribbon cable. I have not tried longer.

o_lampe

@dc42 said in A custom minimal version of Duet 1LC?:

You might find another use for the SAMMYC21 later on.

The SammyC21 was my proposal, the TS wants to strip down the 1LC board which would have only the accelerometer and C21 onboard.

zapta

@dc42 said in A custom minimal version of Duet 1LC?:

You might find another use for the SAMMYC21 later on.

@dc42, would you suggest to use the SAMMYC21 as a starting point for the design rather than the 1LC?

My preference was to start with the 1LC because it's a Duet3d product and thus more likely to have long term support (e.g. firmware versions).

BTW, have you considered to publish guidelines for 3rd party tool boards developers? Tool boards are more form-factor and functionality constrained than main board and custom tool boards will help developing the Duet/RRF eco systems.

T3P3Tony

@zapta it was rather the suggestion to use a Sammcy21 with an accelerometer. rahter than making a custom board.

zapta

@t3p3tony said in A custom minimal version of Duet 1LC?:

@zapta it was rather the suggestion to use a Sammcy21 with an accelerometer. rahter than making a custom board.

Thanks @T3P3Tony. I managed to take accelerometer measurements using SPI and 1.5m of loose wires and my printer have input shaping enabled now

I would like to explore the possibility of open source duet/RRF compatible niche custom tool boards, not just for accelerometers.

o_lampe

@zapta said in A custom minimal version of Duet 1LC?:

BTW, have you considered to publish guidelines for 3rd party tool boards developers?

There's a hardware dev sub forum. I'm sure you get answers to specific questions there.
Writing a guideline, which covers all questions about all available boards in Duet3D universe, is nearly a fulltime job.

It's probably easy to strip down an existing Duet-schematic and reduce features, but adding new features will always require adapting firmware. That's a lot of work for a few? potential users...