This evening I dared to hit the “upload” button after compiling Geeetech’s firmware. I was immediately faced with a huge number of timeouts and other errors that all looked quite horrible, but somewhat reminiscent of a baud rate mismatch.
Enabling verbose mode for the upload showed avrdude being given a speed of 115,200 for uploading the firmware image. A bit of a hunt on the Internet suggested that the actual speed for uploading to my printer should be 57,600, but there’s no obvious place to set the comms rate for the serial device (/dev/ttyUSB0 in my case).
Further hunting revealed that the speed is set in the support files for the Sanguino board I’ve posted about downloading already. In my case I needed to edit $HOME/.arduino15/packages/Sanguino/hardware/avr/1.0.2/boards.txt and change the line that reads
sanguino.menu.cpu.atmega1284p.upload.speed=115200
to
sanguino.menu.cpu.atmega1284p.upload.speed=57600
Restarting the IDE and hitting upload once again resulted in a clean compile and upload to the printer which subsequently restarted itself quite happily.
Now time to do some calibration, I think.