h1. LCGCi – An embedded g-code interpreter and motion-controller for AVR microcontrollers, based on GRBL 0.7b developed for CNC lasers (specifically for www.buildlog.net 2.X lasers)

LCGCi (Laser Controller, G-Code interpreter) is on open source code meant to run on one (or two) AVR microcontroller(s) The software is based on the GRBL software v0.7b. The basic g-code interpreter and stepper controller will are used as the basic workings of the LCGCi. However, several features will be added that make the code specific for laser cutters and will be extended to work as a headless controller (with two AVR’s running together). The slave controller will host the modified GRBL software and its sole purpose is to interpret streamed g-code from the master controller. The master will read g-code from an SD card and pass it via serial to the slave. The master will also monitor variables and pass data through USB to a computer. During a any run, the control comes from the master and will in no way depend on the computer. The computer will be used to set up files and display information.

Development Pathway:

GRBL changes/additions:
1) Add setting options for configuring enable pins as normally high or low as well as sleep state: DONE, Tested
2) Add support for M80 and M81 commands that will enable and disable steppers: DONE, Tested
3) Add support for G28 xyz homing so that one can select which axes to home from command line: DONE, Tested
4) Move limit switch pins from digital to analog to free up digital IO: Not Started
5) Add settings options for homing: Started, tested what is there
6) Add relative positioning from given point: Not Started
7) Add out of bounds check and pin flag: Not Started
8) Add serial communication data flow pin for talking to second Arduino: Started
9) Change motor start to laser on and motor direction to pwm laser power: not started