Emulate a vintage ROM or EPROM with a Raspberry Pi Pico and CircuitPython #CircuitPython #PiDay #RaspberryPiPico @E14Community @baldengineer

The Apple IIe uses a custom microcontroller and ROM chip to put ASCII values from the keyboard into the computer’s memory. How can this function be emulated?

How hard could it be to replace that dual-chip setup with a microcontroller to emulate another kind of keyboard? Bald Engineer tries using an Arduino Mega 2560, Teensy 4.0, and a Pi Pico to replace a vintage ROM chip. See what works AND what does not!

Spoiler alert – of all the candidates, even the Teensy 4.0, the $4 Raspberry Pi Pico did it! With PIO, it’s fast enough to perform the needed timing!

And the amazing thing is that CircuitPython is used to program the PIO and direct the data, even being an interpreted language!

See the video and more on Element14.


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CircuitPython – The easiest way to program microcontrollers – CircuitPython.org


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1 Comment

  1. i would be waiting for the day when we would be able to emulate chips like 440bx and all motherboard functions with a pentium processor, inside a tiny chip!! and lmay those old games!!

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