Problems with GRBL V1.1

Discussion about the arduino based g-code interpreter, grbl
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Problems with GRBL V1.1

Post by Quinten » Tue Feb 14, 2017 4:27 pm

Hello all

I got a CNC router from a friend which had a broken controller.
I have rebuild the complete controller with CW230 drivers and a Arduino uno with GRBL V1.1 and on the PC iv'e got GRBL controller.
I chose for GRBL because I taught it would be a good choice for a beginner.
Now I have a few problems with the machine, I can move it with the arrows but only if I move the Z Axis first.
And sometimes I get the errors 22, 20 and 9 and i can't find anywhere what the mean.
At first I thought it was because of the Chinese Arduino I used with a CH340 serial chip.
So I ordered a Real Arduino uno and the problems became less that way but they are not gone.
Does anybody know how to fix this?
I appreciate the help.


(sorry for my english)

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Re: Problems with GRBL V1.1

Post by WillAdams » Tue Feb 14, 2017 5:55 pm

Your English is fine! (far better than my 1 year and 1 week of high school French).

I suspect we're going to need a bit more information in order to be able to help --- all the specifics of your setup, a compleat wiring diagram, and if possible, photos would go a long way to helping this. Also, your Grbl configuration --- what have you done to adapt the defaults to the specifics of your machine?
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets

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Re: Problems with GRBL V1.1

Post by Picengraver » Wed Feb 15, 2017 1:41 pm

GRBL 1.1_ Error List

Error No. Error Message Description
1 Expected command letter G-code words consist of a letter and a value. Letter was not found.
2 Bad number format Missing the expected G-code word value or numeric value format is not valid.
3 Invalid statement Grbl '$' system command was not recognized or supported.
4 Value < 0 Negative value received for an expected positive value.
5 Setting disabled Homing cycle failure. Homing is not enabled via settings.
6 Value < 3 usec Minimum step pulse time must be greater than 3usec.
7 EEPROM read fail. Using defaults An EEPROM read failed. Auto-restoring affected EEPROM to default values.
8 Not idle Grbl '$' command cannot be used unless Grbl is IDLE.
Ensures smooth operation during a job.
9 G-code lock G-code commands are locked out during alarm or jog state.
10 Homing not enabled Soft limits cannot be enabled without homing also enabled.
11 Line overflow Max characters per line exceeded. Received command line was not executed.
12 Step rate > 30kHz Grbl '$' setting value cause the step rate to exceed the maximum supported.
13 Check Door Safety door detected as opened and door state initiated.
14 Line length exceeded Build info or startup line exceeded EEPROM line length limit. Line not stored.
15 Travel exceeded Jog target exceeds machine travel. Jog command has been ignored.
16 Invalid jog command Jog command has no '=' or contains prohibited g-code.
20 Unsupported command Unsupported or invalid g-code command found in block.
21 Modal group violation More than one g-code command from same modal group found in block.
22 Undefined feed rate Feed rate has not yet been set or is undefined.
23 Invalid gcode ID:23 G-code command in block requires an integer value.
24 Invalid gcode ID:24 More than one g-code command that requires axis words found in block.
25 Invalid gcode ID:25 Repeated g-code word found in block.
26 Invalid gcode ID:26 No axis words found in block for g-code command
or current modal state which requires them.
27 Invalid gcode ID:27 Line number value is invalid.
28 Invalid gcode ID:28 G-code command is missing a required value word.
29 Invalid gcode ID:29 G59.x work coordinate systems are not supported.
30 Invalid gcode ID:30 G53 only allowed with G0 and G1 motion modes.
31 Invalid gcode ID:31 Axis words found in block when no command or current modal state uses them.
32 Invalid gcode ID:32 G2 and G3 arcs require at least one in-plane axis word.
33 Invalid gcode ID:33 Motion command target is invalid.
34 Invalid gcode ID:34 Arc radius value is invalid.
35 Invalid gcode ID:35 G2 and G3 arcs require at least one in-plane offset word.
36 Invalid gcode ID:36 Unused value words found in block.
37 Invalid gcode ID:37 G43.1 dynamic tool length offset is not assigned to configured tool length axis

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Re: Problems with GRBL V1.1

Post by ammoody » Fri Feb 24, 2017 12:45 pm

I would venture a guess that you have electrical interference problems that are affecting the serial transmissions.
Try installing a shielded USB cable with ferrite chokes (like a Tripp-Lite U023-006) and eliminate any USB extensions or USB hubs from the connection.
Also, you may need to flash your Arduino to correct a known issue with the Atmel serial communications:

And on an unrelated note, I also recommend using CNCJS as a GRBL GCode sender:

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