I’ve been asked about how I programmed the bootloader so I’m putting the doco here. For all my AVR work I use a bus pirate v3 with the stk500 firmware. I have a cable I made that adapts the bus pirate to the 6 pin AVR ICSP connector.

For MakeyMakey I made an adapter cable to convert the 6 pin AVR ICSP connector to the MakeyMakey header. I prototyped the cable using individual 0.1″ socket to pin cables and then moved them to single 2×3/1×6 housings to make the cable permanent.

The MakeyMakey schematic decodes the header in two parts
Image

Image

A random ICSP image from google images.
Image

The pin mapping is

Code:
orange  MISO   6x1-6   2x3-1
yellow  MOSI   6x1-5   2x3-4
green   VCC    6x1-4   2x3-2
blue    GND    6x1-3   2x3-6
purple  RESET  6x1-2   2x3-5
grey    SCK    6x1-1   2x3-3

Image