Reviving Frogger's Retro Audio with a Programmable Sound Generator - Using an AY-3-8910 Chip and a Z80 Emulator on a Raspberry Pi

The Frogger arcade video game is considered one of the best of all time. Chris shares his journey to bring the nostalgic sounds of Frogger back to life using the classic AY-3-8910 sound chip and a modern Raspberry Pi setup with coding insights and a fix to the original game's music glitch.

- Chris Cantrell

I have become that guy—the old man at the office who bores the young engineers with tales of how things used to be. DigiKey? The Internet? Back in my day (the early 1980s), we rode our bikes to RadioShack and browsed racks of electronic components by hand—resistors, capacitors, breadboards, LEDs—you name it. I remember the Forrest Mims engineering notebooks on a shelf as I walked in. These were our definitive guides to electronics, op amps, and logic gates. You can still read them on the Web today. Next to the bookshelf was the wall of chips—analog and digital ICs in cardboard packaging, with transparent plastic bubbles so you could see the parts before you bought them. And don't forget to use your battery-of-the-month-club card to get a free battery when you check out.

It was on that wall of chips that I first met my old friend, the AY-3-8910 programmable sound generator. It's a 40-pin DIP chip, packed with features: three voices, a noise generator, and a complex envelope control. Over the years, it has been with me on many projects, including an LED movie project I wrote about in Circuit Cellar #239, June 2010 [1].

Here I am with another retro project featuring the sound chip. In this article, I'll show you how I used Python to talk to my AY-3-8910 from a Raspberry Pi. That isn't revolutionary; you'll find many hardware and software examples on the Internet. But my project has a cool twist.

I'll show you how I ran the original binary code from the Frogger arcade machine in a Z80 emulator on my Pi. For readers who weren't around in the 1980s, Frogger is an action game, the objective of which is to get several little frogs home safely—by keeping them from drowning in a river, or becoming road kill, or the lunch of a snake or alligator. (You can still buy “refurbished” original Frogger games on Amazon, and can even play it as a board game, on PS1, and online.)