nitrologic.github.io/index.md
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Should the Commodore Plus/4 project be parked to make room for some vintage CBM PET?

We begin with document preparation and liking the correct vintage.

The VIC20 machine is quickly catching up to the AppleII with usable keyboard matrix and other IO improvements incoming.

Learn how computers work by building and programming a computer with the classic 6502 microprocessor.
Hurrah, the machine project now has it’s own assembler - burn more ROM


an alternative method of manual program entry / pasting is the cassette
the load command reads from cassette
back in the day the cassette came from the shop, or your mates
and FM radio stations popped up blasting 80’s synth pop, yeesh…

tape counter gets to 1407? umm ok

Processor diagnostics with precursor, action and status columns.


The 1541 disk drive has it’s own 6502 CPU and is running virtual in my terminal.

We single step throught the first instructions, let it run for a bit,
25B4A7 cycles later…
and it returns!
Blinking lights incoming.

Winter 2026 and current appleII emulation development ticks all the boxes in nostalgia section.

I have the terminal mouse mapped to appleII paddle timer, initial findings, woz’s brickout is difficult.

Sabotage is in the I cannot wait to see the little guys come raining down. Early days…

Educational value of this technique worth a case study.

Only 4 new opcodes added to get this far, too cool for school.