alden

We appreciate the feedback. This has definitely been a process, and a lot of work. I like the panels you laid out

We are working on a GUI and would love to collaborate, or just have more than one available if that’s the way you want to go. We are trying to make things as “real” as possible. To that end, we are following Thomas Kramer’s RS274NGC v3 standard for Gcode that can be found here: http://www.isd.mel.nist.gov/documents/kramer/RS274NGC_3.pdf We are also following “CNC Programming Handbook, Third Edition” by Peter Smid. This is as close to a reference manual as exists for CNC control, and is considered the gold standard for CNC machines by many in the field. You can find it on Amazon new and used. The book has the conventions for naming, control layout and behaviors, and other aspects of making realistic controls. Some other info that might be useful may be found on the project wiki under: http://www.synthetos.com/wiki/index.php?title=Projects:TinyG-Developer-Info:

With that in mind, here are some comments (rather lengthy – I’ll try to break it up). These are based on the latest version on the github, version 0.92 (Crocs)

– TinyG handles 6 axes; X, Y, Z, A, B, C. The 0.9x versions allow mapping motors to axes to support common (and uncommon) machine configurations, e.g. XYZA, XYZC, XZC, and dual gantry machines like the lumenlabs (XYYZ). While the board supports 4 motors, the firmware design allows multiple boards to be slaved together for more than 4 axis control. Displays should take these mappings and all 6 axes into account. A common XYZA like you have is a good starting point.

– As of 0.92 the firmware can return a running status report. I typically set it to respond every 50ms when running, and at the end of each gcode block. This is designed to update the display. It returns a line in JSON format like below. Units are in prevailing mode. In the example mm=1, so units are in mm and mm/min. If ABC axes were used it would also return an “abc”: tuple, returning in degrees.

tinyg[mm] ok> g0 x10
tinyg[mm] ok> {“ln”:204, “xyz”:[0.017,0.000,0.000], “vel”:28.88, “mm”:1}
{“ln”:204, “xyz”:[0.136,0.000,0.000], “vel”:121.68, “mm”:1}
{“ln”:204, “xyz”:[0.648,0.000,0.000], “vel”:537.52, “mm”:1}
{“ln”:204, “xyz”:[1.745,0.000,0.000], “vel”:796.72, “mm”:1}
{“ln”:204, “xyz”:[3.200,0.000,0.000], “vel”:991.92, “mm”:1}
{“ln”:204, “xyz”:[4.486,0.000,0.000], “vel”:800.00, “mm”:1}
{“ln”:204, “xyz”:[5.771,0.000,0.000], “vel”:800.00, “mm”:1}
{“ln”:204, “xyz”:[7.056,0.000,0.000], “vel”:798.56, “mm”:1}
{“ln”:204, “xyz”:[8.277,0.000,0.000], “vel”:715.36, “mm”:1}
{“ln”:204, “xyz”:[9.253,0.000,0.000], “vel”:504.16, “mm”:1}
{“ln”:204, “xyz”:[9.801,0.000,0.000], “vel”:219.04, “mm”:1}
{“ln”:204, “xyz”:[9.983,0.000,0.000], “vel”:46.24, “mm”:1}
{“ln”:204, “xyz”:[10.000,0.000,0.000], “vel”: 0.16, “mm”:1}

– Some comments on the buttons, and some naming conventions from Smid:
If “Stop” is a command to pause program execution it’s CNC name is “Feedhold”. Not very intuitive, but accurate.
“Resume” is “Cycle Start”. This starts the program as well as resumes after feedholds. Perhaps this is also the Start Process button
TinyG currently does not do flood. We can add this in if people need it.
Not sure what Set Outputs and Read inputs does
You will want a Zero button to set the current position to 0,0,0

– General items

We are maintaining close contact with the grbl project and want any GUI we do to be able to work with both grbl and TinyG. This involves some compatibility measures that are too lengthy to go into here.

What language / framework are you using or planning and what are you cross-platform goals? We are aiming for full cross-platfom support. many current GUIs suffer from very difficult installations due to this. Serial libs are different, UI is different, etc. This also deserves further discussion.

Thanks for the work on this. Looks great.

– Alden

What .hex are you using? It should be grbl_0_6b_atmega328p_16mhz_9600_with_grblshield_patch.hex or Chamnit’s 0.7d on github.

How did you program grbl onto the arduino hardware? Did you use an AVRdude and atmel programmer?

I am not familiar with minicom so I can’t help you there. Sounds like no transmitted chars are getting through. I’m assuming you have the serial communications for receive set up correctly or you wouldn’t have gotten the response. You might check any special transmit settings.

Have you followed the instruction found here?
http://www.synthetos.com/wiki/index.php?title=Getting_grbl

It directs you to the grbl project page on installing here:
http://dank.bengler.no/-/page/show/5470_grbl?ref=mst

The .hex you want is here. Get the latest 07b version in the Downloads area.
https://github.com/chamnit/grbl

Alternately, you can use our version – but it’s not as advanced:
https://github.com/synthetos/grblShield
unzip this file: grbl_0_6b_atmega328p_16mhz_9600_with_grblshield_patch.hex.zip

You can’t really drive grbl from Termite – at least not any files that are more than a few lines long. We are developing a console program for grbl and TinyG. Until that’s ready you might want to try gctrl that can be found here:
https://github.com/damellis/gctrl

Chris – I found and fixed the issue we encountered yesterday. The drift in non-power mode axes has been eliminated. I will post on github as 0.911. I’m around today to try it out. Ping me if you want to test. – Alden

I’m going home soon and am going to try running your pocket code before I have go go out tonight.

I’ll be around most of the day Saturday. We can do a hangout, or we could set up to connect on gchat and use a video call. I’ll send you my gmail addr off list.

No problem, it’s not a waste of time at all. As these questions are asked they get recorded in the forum. Have fun with your board!

OK. If the grblshield is plugging into the protoshield then you will need to make sure the 5v line is powered with 5v. grblshield requires the 5v for the stepper logic (Stepper motor power is provided separately from the connector on the grblshield). If the RBBB is running 3.3v logic there should still be enough voltage to drive the 5v inputs on the grblshield. The grblshield does not send any output pins to the arduino – or this would blow up the MCU chip.

Schematics for the grblshield can be found here:
https://github.com/synthetos/grblShield

We also recommend using the patched hex found there, or Chamnit’s fork found here:
https://github.com/chamnit/grbl

If you use Chamnit’s be sure to use the edge branch

grbl really wants to run in an atmel atmega328p, not a 168, so that’s also worth checking. It’s possible to run from a 168, but you would have to hack the code yourself to achieve compatibility with the grblshield.