i was able to create the Digicomp II onto a normal sized board! (even though it is modified)
Digicomp II was a 1965 marble powered computer that could add, subtract, multiply, divide, and count. but since this is small and had to limit the amount of bits, it can only add and multiply. (but hey, better than nothing right?)
how to add: set a number into the memory registers by changing the direction of the ramps (left for 0, right for 1) and set a number into the accumulator, then run it.
how to multiply: set a number into the multiplier, and set a number into the memory (leave the accumulator empty) the run it.
have a better design? let me know!