I just got myself a Smoothieboard for my CNC and was wanting to use

I just got myself a Smoothieboard for my CNC and was wanting to use it with Chilipeppr. I managed to get the json server to connect to it but I can’t seem to get Chilipepper to connect to the server. I tried the grbl workspace w/the grbl buffer but it kept disconnecting the Smoothieboard.

Anyone got any hints on what workspace, etc. I should be using?

Not compatible. LaserWeb.

My understanding is Smoothie does have a Grbl mimic mode. You could try that in the Grbl workspace. Not sure if it mimics old Grbl or v1.1, but if 1.1 then try /jpadie workspace.

If it doesn’t work, would you be up for creating a workspace that forks the TinyG workspace, but is modified to take into account the nuances of Smoothie?

@jlauer yeah, I’d be willing to fork it. I probably won’t know what I’m doing(still getting used to the Smoothie) but I’ll be willing to test it for sure.

Cool. I know the Smoothie guys would love to see a ChiliPeppr workspace happen. My gut tells me that you would have to still put your Smoothie in Grbl buffer flow mode so Serial Port JSON Server handles buffer flow correctly.

I already have “grbl_mode true”. Do I need to set anything else?

I don’t really know. I’ve never used a Smoothie. Best to just experiment. Feel free to post lots of screenshots to ask questions on.

@ehrichweiss ​ if you can connect the smoothie board in CNC mode to a serial terminal and capture the outputs of the following I could probably find time to add initial support for smoothiboard grbl mode this weekend.


@Justin_Adie , ok. I’ll try to get everything later tonight.

Ok, the results are below. I’ll list the command and on the next line the response. I’m retaining the format it was output in just in case the spaces, etc. are necessary.

error:Unsupported command - $

? (this one gives me the first line before I hit return, then I get the second line when I hit return)

error:Invalid statement

[G0 G54 G17 G21 G90 G94 M0 M5 M9 T0 F2000.0000 S0.8000]


error:Invalid statement

eek. so smoothis doesn’t really support all the standard grbl dialect. and the dialect is partially supported is the out-of-date 0.9x branch.

that’s annoying.

@ehrichweiss can you post the result of sending the following command via the serial port, please:


Also, it seems that in fact smoothieboard uses grbl 0.8 and not 0.9. So it will not report probe contact in the same way as a more recent grbl board. if you need probing and auto levelling you will need to fork the auto levelling widget and make the needed fixes.

out of interest, if you run the following commands, it might be useful to see what the board reports.

G21 (set to mm)
G38.2 Z-2 F5 (probe at slow feedrate until triggered or reach -2mm)

whilst it is running, artificially trigger a probe response and let us know the board’s response

I’ve no idea whether probing will work - but I sincerely doubt it. i’d need a smoothieboard to test properly.
but I have rewritten parts of the grbl widget to cater for the limited smoothieboard support of the very old grbl interface.

if it is the case that you can instruct smoothieboard more generally over serial, without being limited to the gcode command set (e.g. the console commands work), then we might be able to extend support to get and set config items, support probing, load to sd card etc. but really, without the smoothieboard there is little point in me doing this work - someone with a board and the desire should take it on.

the experimental workspace is at http://chilipeppr.com/smoothieboard

I haven’t had time to play with the Fiddle for my Smoothie yet but here’s something that might be of value… GRBL 1.1 firmware… I haven’t tried compiling it yet but it may help someone…