An architecture and name change: the T-1 is now the ED-64, and it is no longer a stack machine. The changes were made for several reasons:
- I decided I really wanted to be able to load programs into the memory manually from the operator panel, and the Harvard architecture of the T-1 (and 10 bit program word) wouldn't allow that.
- For an 8-bit word formatted [Opcode][Address], a 2-bit instruction width means a 64-byte address space. Since I am avoiding multi-byte instructions, that means I only need to complete a single 64-byte core matrix (which I already have).
- Only 4 instructions drastically simplifies the control logic and ALU, while still allowing enough complexity to do interesting things.
- I got bored with the 'T-1' name!