Pin Constraints
I think I’ve found answers for all the big questions about Tiny CPU’s design, and I’m ready to start creating the final schematic and board layout, save for one issue: pin constraints. I need to constrain which signals are assigned…
Month June 2010
Tiny Device
Tiny CPU just barely squeezes into a 128-macrocell CPLD, and so I’ve designed a companion chip called Tiny Device to handle other interface functions. It utilizes a second CPLD, and was originally envisioned as a simple address decoder, but its…
Bank Switching
The Tiny CPU design has a 10-bit address bus — that’s all I could fit in the constrained space of the CPLD. 10 bits means 1K of addressable memory, which is practically nothing. I had planned to improve on this…
2D Graphics Thingy?
Maybe 3D Graphics Thingy isn’t dead after all. One of my goals for the creation of Tiny CPU was to get more comfortable with programmable logic design, and custom circuit board development, and I’ve certainly done that. Once Tiny CPU…
Power Research
I’d like Tiny CPU to be flexible with its power requirements. The Tiny Test Board that I made uses an external, 5V regulated power supply, and so doesn’t have any on-board voltage regulation. That works fine, but I’d like the…
CPU Angst
I’m starting to fear that Tiny CPU is a short-sighted design. It occupies a strange spot between ultra-simple soft-CPUs like MCPU, and much more capable soft-CPUs like PicoBlaze. The hardware is nearly as complex as PicoBlaze, but the functionality is…