commands.txt

Write HEX via AVR ISP (arduino)
sudo avrdude -c avrisp -P /dev/ttyACM0 -p usb646 -U flash:w:filename.hex:i -b 19200

Read HEX via AVR ISP (ardino
sudo avrdude -c avrisp -P /dev/ttyACM0 -p usb646 -U flash:r:filename.hex:i -b 19200

flash firmware via DFU
sudo dfu-programmer at90usb646 erase --force
sudo dfu-programmer at90usb646 flash XO87_rgb.hex

fix fuses (danger!)
may need to inject clock signal on XTAL2 or XTAL1 (pins 23 or 24) from pin3 on arduino
sudo avrdude -e -c avrisp -P /dev/ttyACM0 -p usb646 -U lfuse:w:0xDE:m -U hfuse:w:0xD3:m -U efuse:w:0xFB:m -b 19200

ISP interface connector on board
Top to bottom

1 - pin 3 - UVcc
2 - pin 11 - PCINT1/SCLK
3 - pin 12 - PCINT2/MOSI
4 - pin 13 - PCINT3/MISO
5 - pin 20 - RESET
6 - no connection
7 - pin 6 - UGnd


Arduino UNO

1 - 5V
2 - pin 13
3 - pin 11
4 - pin 12
5 - pin 10
6 - not used
7 - GND
* - pin 3 for injecting clock signal if needed (only if fuses are wrong)