Back to the Scratchpad board

i4004 CPU Block Diagram

As I mentioned in the previous post, I've started working on the Scratchpad board again. This is the board that implements the 16 x 4-bit array of internal registers.

Internally, as depicted at the far right side of the i4004 CPU block diagram, this is actually an 8 x 8-bit DRAM array. It's quite similar to the 4 x 12-bit array used in the Instruction Pointer, which I successfully implemented some years ago.