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A project log for JACA 1 & 2 Homebrew Computer

JACA - Just Another CPU Again Homebrew CPU, starting by a simple POC 4-bit CPU on circuit simulator soft. (done), then 8-bit (in progress)

Andre BaptistaAndre Baptista 06/05/2019 at 16:420 Comments

According to the plan I made on December 2018, I'm already more than one month late.

Let's see what we have currently:

- Registers board built. Registers A and E working. Loading literals (e.g. LD A, 5). The other 6 registers are just a matter of insert on DIP sockets and reprogram the EEPROM to write code to test them. Lacks testing the copy from one register to another.

-ALU connected and working (at least the ADD instruction). Saving result to register fine.

-The Program Counter and Memory, which is the only module still on breadboard is being redone on a universal PCB. That's a more demanding work as it seems. Some 8 hours of soldering estimated. At my self imposed pace of 1 hour per day, it's very slow to see progress. After that I will need to put circuit to manage the conditional and unconditional jumps.

Write down these logs help me keep motivated as it's easier to see progress looking behind.

Thanks for reading.

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