
YACC – Yet Another Custom CPU
Finally time to try building a custom CPU from basic TTL and other “simple” ICs — Thanks for taking a look.
The One Page Computer Project, provides the tools and resources to learn computer science starting from the basics of digital logic through to a fully working custom CPU with a user defined instruction set, assembler and one day an operating system with standard tools.
The project is currently under development as a personal project. The basic idea has kicking around inside my head for years (45 years to be exact), but until recently never made it to the top of my list. Now I am exploring if this project might be interesting to others, perhaps as an educational tool or maybe just a fun project.
I am interested in speaking with:
High school computer science educators
Freshman and sophomore college computer science educators
Electronics enthusiasts
YACC1-2020 (This time for sure)
ALU
Soldered Up Bus Board
The boards bus are here
BUS BOARD (Motherboard)
Bus Connector

Yacc1 will be a multi-board system requiring a motherboard, really more of a basic bus-board, for cards to plug into. For my previous 1802 projects single row breakaway headers with a simple bus-board made of either Veroboard or a simple PCB had all the pins, a grand total of 3X, required. This […]
Opcodes for YACC1
Yacc1 in Logisim
This is a working but not fully tested working model of YACC1 in Logisim Files are available here https://github.com/ksr/YACC1
New block diagram for YACC1
Added 1) stack pointer to support call/return and interrupts 2) branch register for conditional branching