Marcel van KervinckToday I realised that no homebrew CPU project can claim completeness without a blinking light. Lacking free output pins (all 8 are used for video), I hooked up an LED to the unused address pin 15, and use that as alternative.
I'm getting into some serious problems with breadboard fatigue in the EEPROM area. One of the ROM's just keeps popping out. The next phase is therefore to document the circuit in KiCad and convert it into a PCB.
[ Spoiler: the display is an older selfie, as witnessed by the incomplete wiring and background. The on-screen LED is just a 3x2 pixel area turning red at the same time as the breadboard LED. The scrolling is smooth in real life, but due to mismatch with my phone, it may appear jumpy. ]
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That's fun! And I am impressed by the small component count for such a result!
If you don't want to use breadboard, and if you still want to experiment, change something, you should also consider using the wrapping technique.
But if you already have your final design, of course, a PCB is of course faster and better technique.
Finaly, I have one question : what kind of programs/applications do you plan to code for this machine?
Are you sure? yes | no
Thanks. I learnt about wire wrapping only after I was already over 80% of the breadboard build. I plan on stuff like Space Invaders, Pac Man... Scrollers should be possible, as well as fake-3D road games.
Are you sure? yes | no