Giles Booth has written up a great educational project that involves using a micro:bit to show you how a CPU/processor works. This is what he said about his intentions:
I decided my micro:bit CPU would be a 5-bit computer, rather than 8-bit as you might expect. This is because I want to show the contents of memory, instructions and so on using the LEDs on the micro:bit’s display, which is made up of 5 rows of 5.
He decided that it would have 4 “instructions” that it could take, as follows:
- Load memory location to A
- Add memory location to A
- Output A
As he acknowledges, this is very limited as an instruction set but it does provide a terrific proof-of-concept for budding computer designers/engineers.