Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Curvy Centerfold

What do you get when you combine a Raspberry Pi 4B, a Kaypro keyboard, and a 9″ Apple ], you get the coolest AVR development workstation I’ve seen in a while.

A Raspberry Pi-based AVR workstation that uses a Kaypro keyboard and 9" monochrome Apple ][c display.
Image by [John Anderson] via Hackaday.IO
As you may have guessed, I really dig the looks of this thing. The paint job on the display is great, but the stripes on the keyboard and badging on are on another level. Be sure to check out the entire gallery on this one.

About that keyboard — [John] started this project with two incomplete keyboards that each had a couple of broken switches. Since the two keyboards were compliments of each other parts-wise, they made a great pair, and [John] only had to swap out three switches to get it up and clacking.

In order to make it work with the Pi, [John] wrote a user-mode serial driver that uses the uinput kernel module to inject key events to the kernel. But he didn’t stop there.

Although the Pi supports composite video out, the OS doesn’t provide any way to turn off the chroma color signal that’s modulated on top of the basic monochrome NTSC signal, which makes the picture look terrible. To fix that, he wrote a command-line app that sets up the video controller to properly display a monochrome NTSC signal. Happy AVRing on your amazing setup, [John]! Continue reading “Keebin’ With Kristina: The One With The Curvy Centerfold”

Upgrade Board Turns Typewriter Into A Teletype

It may come as little surprise to find that Hackaday does not often play host to typewriter projects. While these iconic machines have their own particular charm, they generally don’t allow for much in the way of hardware modification. But then the IBM Wheelwriter 1000 isn’t exactly a traditional typewriter, which made its recent conversion to a fully functional computer terminal possible.

A product of the Computer History Museum’s [IBM 1620 Jr. Team], this modification takes the form of a serial interface board that can be built at home and installed into the Wheelwriter. The board allows the vintage electronic typewriter to speak RS-232 and USB, so it can be connected to whatever vintage (or not so vintage) computer you can imagine. The documentation for the project gives a rough cost of $150, though that does assume you’ve already got a Wheelwriter 1000 kicking around.

The GitHub repository includes everything you need to create your own board, and there’s even a highly detailed installation guide that goes over the case modifications necessary to get the new hardware installed. It also explains that you’ll want to get a new keycap set for your Wheelwriter if you perform this modification, as the original board doesn’t have all of the ASCII characters.

So why adapt an old electric typewriter to function as a teletype? As explained by the [IBM 1620 Jr. Team], there are projects out there looking to recreate authentic 1960s-era computing experiences that need a (relatively) affordable paper terminal. The originals are too rare to use in modern recreations, but with their adapter board, these slightly less archaic input devices can be used in their place.

Once you’ve built your new teletype, or in the somewhat unlikely event you already have one at the ready, we’ve seen a couple of projects that you might be interested in to put it to use.

Vintage IBM Daisywheel Prints Again After Reverse Engineering

Just before the dawn of the PC era, IBM typewriters reached their technical zenith with the Wheelwriter line. A daisy-wheel printer with interchangeable print heads, memory features, and the beginnings of word processing capabilities, the Wheelwriters never got much time to shine before they were eclipsed by PCs. Wheelwriters are available dirt cheap now, and like many IBM products are very hackable, as shown by this simple Arduino interface to make a Wheelwriter into a printer.

[Chris Gregg] likes playing with typewriters – he even got an old Smith Corona to play [Leroy Anderson]’s The Typewriter – and he’s gotten pretty good with these largely obsolete but lovable electromechanical relics. Interfacing a PC to the Wheelwriter could have been as simple as scrounging up an original interface card for the machine, but those are like hen’s teeth, and besides, where’s the sport in that? So [Chris] hooked a logic analyzer to the well-labeled port that would have connected to the interface card and reverse engineered the somewhat odd serial protocol by banging on keys. The interface he came up with for the Wheelwriter is pretty simple – just a Light Blue Bean Plus and a MOSFET to drive the bus high and low for the correct amount of time. The result is what amounts to an alphanumeric printer, but with a little extra code some dot-matrix graphics are possible too.

Having spent a lot of time reverse engineering serial comms, we can appreciate the amount of work this took to accomplish. Looking to do something similar but don’t have the dough for a logic analyzer? Maybe you can free up $22 and get cracking on a similarly impressive hack.

Continue reading “Vintage IBM Daisywheel Prints Again After Reverse Engineering”