a while back I did one of the free MOOC courses on computer architecture. The course took us through building a 32 bit RISC CPU from first principles. I learned a LOT on this course.
Perhaps we could do something similar, say partially implement an AVR processor? 8 bits is ‘modest’ enough to fit most low end devices. Components like the ALU provide great opportunities to learn about combinational circuits. AVR architecture is RISC and pretty ‘clean’, shouldn’t be difficult to get something going.
Boardwise you’d need:
on board oscillator
slide switches - for global settings like run/single step, display value selection
push buttons - to single step
a display of some sort - 4 digits min
breakout connectors - (future projects)
on board programmer (desirable)
vga/hdmi (nice to have)
To save money, board manufacturers cut back on the number of switches, displays, connectors etc. A cheaper board will generally mean adding external circuitry.
There is no hard requirement for Xilinx, it just happens to be the toolset I am familiar with. There seems to be a bunch of cheap boards based on Altera Cyclone IV on eBay. I’ve ported VHDL from Altera to Xlinix before, found it straight forward.
What do people think?