Sprout24 CPU

Sprout24 is a "know-your-roots" computer processor — designed and built from the ground up as a teaching tool to help introduce the basics of computer science and demystify how computers work.

March 8, 2023 — Placed order for all remaining CPU boards, including the Southeast and East Bridge boards. Now we wait.
March 3, 2023 — My bank flagged the PCB order as suspicious, so I had to call them to confirm it was legit. In the meantime I noticed an omission in the Register File board, so I put the order on hold and made a revision B for the Register File and West Bridge boards. At this point, I'm close enough on the layout of the Southeast board that I'm going to wait to try the order again until I can include the Southeast and East Bridge boards too.
February 28, 2023 — The Register File, Register 01, Northwest, and West Bridge board designs are now finished, and I just placed an order for those plus the Control Unit and ALU Core boards. There will be a lot of things to test once this order shows up.
February 1, 2023 — The Control Unit and ALU Core boards are ready to order, though I'm going to wait until I have a couple others ready to save on shipping costs.

Next to design are the "Northwest" board that includes components related to the program counter and stack pointer, and the "Southeast" board that relates to the instruction and status registers.

And I now have a tentative physical layout for how the individual boards will fit together into a complete CPU. Two additional helper boards with no components will sit below the rest of the boards for physical support and for routing busses between the boards above.
December 22, 2022 — The CPU's Control Unit is working and tested in the emulator, and now it's time to turn it into hardware. More details and a demo in this video.

We've heard that computers work entirely in ones and zeroes... but what does that even mean? How is that really enough to let modern computers, phones, and devices do all the amazing things that they can?

Let's take a look together at how that all works, using the design of the Sprout24 along the way to illustrate how simple pieces working together like an orchestra can make beautiful things possible.

Development is currently underway, with a launch expected in 2023. I'm looking forward to sharing it with you.

~ Autumn

register complete
register01 ordered revA
registerfile ordered revB
alu-core ordered revB
alu-adder complete
alu-logic complete
alu-shifter complete
controlunit ordered revA
northwest ordered revA
southeast ordered revA
westbridge ordered revB
eastbridge ordered revA
extra-cpu boards
mainboard to do after full cpu tested w/sbc
ram proof-of-concept w/sram good
isabridge rough design sketch
shiftbus-read complete
shiftbus-write complete
instruction set complete
emulator working
assembler working