PJ5 TTL CPU Project
Here you’ll find details and updates about our home built TTL based CPU
Latest from the Blog
This program counter has turned into a bit of a saga, but the PCB layout is finally complete. Firstly the 8 DIL chips with digits on are actually going to be some TIL311’s that I got as new old stock from eBay, I just couldn’t find a model so I made one up from aContinue reading “Program Counter, the revenge”
Finally, after about 2 weeks of pain, the program counter schematic has been completed. It’s also been simulated and seems to be working a treat. Why so long? well, some daft person (that would be myself, Paula) decided she wanted interrupts, which meant the program counter became extremely complex very quickly. It took about threeContinue reading “Who’s daft idea was that?”
A few people have asked what the Architecture of the PJ5 CPU is, and we’ve kept things kind of quiet whilst we were developing it, now that the instruction decode is under way we’re fixing the instruction set. First of all here’s a drawing of the CPU; The ALU is split into 4 parts; TheContinue reading “Architecture & Instructions”
Get new content delivered directly to your inbox.