The Hackability of an Arduino With the Retro Swagger of a C64

Some people are excited about single-board computers (SBCs) that fit inside USB ports or whatever. Which is cool and all, but some of us prefer the sturdy beige majesty of a Commodore 64. Powered by eight bits of warm nostalgia and decorated with shiny keycaps that go all the way down, your beloved C64 is now good for more than just binging on Jumpman Junior (assuming you can find the floppies).

Remember that port on the back of your Commodore 64? The one you never used? Well we think it’s about time you plugged something into that port. Specifically, we recommend a Zion adapter connected to one or more Zeus LT expansion boards. Together, these two boards open up a world of possibilities:

• Give your Commodore 64 dominion over your home automation system by connecting it to lights, cameras, sensors, automatic locks, motors, and just about any 220 V appliance. It is highly unlikely to leverage targeted marketing strategies to monetize whatever data it might gather in the process...
• Design, test, and debug Internet-of-Things (IoT) solutions while using a keyboard that doesn't suck.
• Develop innovative retro-gaming hardware and software that brings motion control, sensor networks, computer vision, and other "real world" input and output to the glorious world of 8-bit entertainment.
• Learn or teach basic electronics—and BASIC programming—using a familiar, trusted platform that you can understand fully but that can (still) handle whatever computation might be required.
• Look good doing it.

Zeus LT Board + Single-Port Adapter

This has everything you need to make the Commodore 64 external I/O magic happen:

• One single-port adapter that plugs into your Commodore 64
• One 15-pin D-sub connector cable to connect the adapter to the Zeus LT I/O board
• One Zeus LT board that has:
  • 8 inputs for sensors
  • 4 outputs controlled by relays
  • 4 outputs controlled by TRIACs
  • 4 signaling LEDs connected to the relay outputs
  • A single power-on LED
  • A beeper attached to the first relay output. (Don't worry, you can disable it.)

Zeus LT Output Specifications

Zion F Multi-Port Adapter

While each Zeus LT + Single-Port Adapter comes with an adapter to connect a single Zeus LT board to your Commodore 64, you might want even more I/O expansion. In that case, the Zion F Multi-Port Adapter is for you. With it, you can connect up to four Zeus LT boards to your C64. Features include:

• Exposed male edge connector for C64 expansion port
• Reset button
• Four 15-pin D-sub connectors to connect up to four Zeus LT boards
• Female pass-through cartridge slot (for when Zeus LT is not in use)

They Call it BASIC for a Reason

Even if it doesn’t bring back fond memories of your first, halting steps across the plush living room carpet of computer programming, BASIC is nonetheless intuitive and easy to pick up. If you want to learn more about BASIC programming, we recommend this Two-Bit History post by Sinclair Target. Meanwhile, consider the LED sequence shown in the video above. That was driven by the following six lines of code:

No, You Don’t Have to Save Your Code on a Floppy

It turns out, there are a lot of people who love their C64s, and some of those people make cool stuff. The image below shows an SDIECplug, which is an open source device similar to the SD2IEC. Your Commodore 64 can use either of these devices to read from and write to modern flash memory cards. The smallest and cheapest such card has plenty of room for all of the BASIC programs you’re every going to write.

Of course, you certainly can save your code on a floppy. And if you’re lucky enough to have a 1541 tucked away in a closet somewhere, why wouldn’t you? (Don’t forget, all you need is a hole punch to double the storage capacity of those single-sided floppies!)

While you’re looking through your closets, keep your eyes peeled for other old hardware:

• Any television or monitor that accepts composite input will work as a display for your Commodore 64, though you will need to find, purchase, or make an appropriate A/V cable
• The Zion F has a pass-through slot so you can insert cartridges and other expansion modules, without removing the adapter board, as long as your Zeus LT is idle
• Like the villain in some old movie, you can now use that joystick to control the real world: adjust a thermostat, rotate a security camera, dim the lights, lower the blinds, or route power to your smoke machine.

Support & Documentation

Zeus LT is open hardware, and we will publish all design files. Each Zeus LT board comes with a printed quick-start guide. Full documentation will be available online, as will a repository of sample code that covers various application of Zeus LT. There is also a technical support website and a customer forum. Finally, you can reach us using Crowd Supply’s Ask a technical question form.