I worked with Mitch on "bringup" of the OLPC 1.5 hardware and got to see him doing amazing things. The best was when he needed to initialize the memory controller to make RAM available and so he flashed a small Forth system that could run strictly within cache and then connected to that with a serial port and poked the memory controller registers until he had the RAM working. Made an impression on me :-).
Relevant blog entry: http://lukego.github.io/blog/2012/10/28/firmware-vs-software...
I worked with Mitch on "bringup" of the OLPC 1.5 hardware and got to see him doing amazing things. The best was when he needed to initialize the memory controller to make RAM available and so he flashed a small Forth system that could run strictly within cache and then connected to that with a serial port and poked the memory controller registers until he had the RAM working. Made an impression on me :-).