Below are the old instructions for grbl running on Mega 2560. It is kept here for reference. Newer and improved versions exist. Check out the Mega 2560 page.
\Downloads\arduino-1.0.5\hardware\tools\avr\bin\avrdude.exe -C \Downloads\arduino-1.0.5\hardware\tools\avr\etc\avrdude.conf -c wiring -p atmega2560 -P\\.\COM6 -b115200 -D -Uflash:w:grbl.hex
This is the same command with much more debugging and verification turned off:
\Downloads\arduino-1.0.5\hardware\tools\avr\bin\avrdude.exe -C \Downloads\arduino-1
.0.5\hardware\tools\avr\etc\avrdude.conf -v -v -v -v -c wiring -p atmega2560 -P\\.\COM6 -b115200 -F -V -D -Uflash:w:grbl.hex
A few things I had to do:
- I needed to load the most recent Arduino drivers from 1.0.5 for my Windows 7 64 bit system to see the Mega2560.
- I changed to the directory that contained the hex file
- The ‘wiring’ programmer type was needed
- None of that worked until I opened up the Arduino IDE and sent down a sketch. This somehow enabled COM6 and now I could run the command line avrdude command.
You can probably turn off some of the above options, like the verbose mode.
Some useful links:
http://false.ekta.is/2011/05/avrdude-5-10-arduino-mega-2560-command-line-uploading/
http://stackoverflow.com/questions/10521813/eclipse-avr-programming-atmega2560
Also, this appears to be the only two four-axis grbl fork currently up on github which add’s M7 coolant mist support by LETARTARE:
https://github.com/LETARTARE/Mega2560-grbl-0.81
This is the hex file I built from the above source code using WinAVR.
— This file is buggy! Try using the older version that ends with 38400.hex —
https://zapmaker.org/downloads/grbl-081-letartare-arduino-mega2560-16u2-57600.hex
Here is an older version closer to the original 4-axis (pre-LETARTARE’s changes):
https://zapmaker.org/downloads/grbl-081-arduino-mega2560-16u2-38400.hex
This is the original four axis fork that is no longer present:
https://github.com/EliteEng/grbl
After running and installing and figuring out the proper baud rate, I get a nice new Grbl response, with four axis control (screenshot is for original hex file, not LETARTARE’s, which works at 57600 baud instead):
