Quick guide
To get your Arduino to control a plotter, following steps are needed:
Windows USB driver
Connect your Arduino with your PC, on windows 10 the needed USB driver will be installed automatically, if not: the cheap Arduino clones often uses a CH340 chip. Check here for more information https://www.google.de/search?q=arduino+ch340.
Grbl firmware
Download and unzip GRBL-Plotter. Start the program XLoader.exe. Select the desired firmware, correct device and the correct com port, then upload the firmware. With the shown settings, the upload took 18 seconds.
- grbl_v1.1h.20190825.hex is the latest regular grbl firmware for Arduino uno and nano, from https://github.com/gnea/grbl
- grbl_v1.1f_Servo.hex as above, but with Spindle-PWM adapted to RC-Servo specification (1ms - 2ms), from https://github.com/cprezzi/grbl-servo
- grbl-Mega-5X-v1.1l.20190605.hex 5 axis version for Arduino Mega2560 only, from https://github.com/fra589/grbl-Mega-5X
After successful upload, close XLoader and reset the controller.
1st connection
Install GRBL-Plotter by starting 'setup.exe' from the unzipped folder. Start GRBL-Plotter and select the correct COM-port for the controller. After successful connection, grbl sends a start-up message "Grbl 1.1h ['$' for help]".
Now the buttons inside the GUI are enabled and the stepper motors can be controlled.
Configuration of grbl
After pressing "$$", grbl lists the stepper motor settings, which must be adapted for each machine. Check the grbl-Wiki for more information. The screenshoot shows the initial settings after the installation of grbl.
The main settings are $3, $10x, $11x (x=0,1 or 2 depending on axis) to get the stepper motors running in the correct direction. The correct direction means:
- +X = to the right
- +Y = to the back
- +Z = upwards
Note: a too large number for $10x (steps/mm) and $11x (max. speed) will cause problems.
The product of $10x and $11x must stay below 1800000 to avoid pin frequencies above 30 kHz.
E.g. $100=250, $110 = 7200 is at the edge.
More information here: quick-guide-to-setting-up-your-machine-for-the-first-time