EXPS/2 Keyboard Adapter Translates PS/2 And USB To MSX

Say what you will about suitcase computers, but at least most of them still have their keyboards with them. [danjovic] has this vintage Brazilian computer from the 1980s called a Gradiente Expert. These were MSX machines with Z80 chips that ran BASIC, DOS, and CP/M, and they looked like state-of-the-art dual-deck stereo systems. You can still find them pretty easily, but sadly, most of them have lost their rad mechanical keyboard with its giant arrow keys and proprietary connector.

If you now want to get one of these awesome pieces of computing history and would like to be able to talk to it, [danjovic] has you covered with the open-source EXPS/2 keyboard adapter. It will allow you to connect either a PS/2 keyboard or a USB keyboard in fallback mode to the Expert using an ATMega328P and a bespoke DIN-13 to DB-13 cable. As it turns out, there’s a wealth of information on MSX keyboard matrices out there.

How much do you know about the USB keyboard interface? If you want a warehouse of information delivered to your brain in the most pleasant way possible, go watch [Ben Eater] break it down with pen and paper.

AlphaSmart Neo Teardown: This Is The Way To Write Without Distractions

History will always have its in-between technologies — that stuff that tides us over while the Next Big and Lasting Thing is getting the kinks worked out of it. These kinds of devices often do one thing and do it pretty well. Remember zip drives? Yeah you do. Still have mine.

The halcyon days of the AlphaSmart NEO sit in between the time where people were chained to heavy typewriters and word processors and the dawn of on-the-go computing. Early laptops couldn’t be trusted not to die suddenly, but the NEO will run for 700 hours on three AAs.

The NEO stands for the freedom to get your thoughts down wherever, whenever, without the need for a desk, paper, ink, ribbons, power cords, and the other trappings that chain people indoors to flat surfaces. And that’s exactly what was so tantalizing to me about it. Inspiration can truly strike anywhere at any time, so why not be prepared? This thing goes from off to blinking cursor in about a second and a half. There’s even a two-button ‘on’ option so you don’t run the battery down or accidentally erase files while it’s in your bag.

These might be the world’s greatest scissor switches.
L-R: DC power, IR, USB-B, and USB-A for connecting to a printer.

I bought this funny little word processor a few years ago when I wanted to attempt NaNoWriMo — that’s National Novel Writing Month, where you write 50,000 words towards a novel, non-fiction book, or short story collection in any genre you want. It averages out to 1,667 words a day for 30 days. Some days it was easy, some days it was not. But every non-Hackaday word I typed that month was on this, my Mean Green Words Machine.

Continue reading “AlphaSmart Neo Teardown: This Is The Way To Write Without Distractions”

Repurposing A Palm Portable Keyboard

Typing comfortably on a Smart Phone is best done using an external keyboard, especially if you spend a lot of time on IRC or use other chat apps. Obviously, the keyboard needs to be portable too. [cy384] felt the current crop of portable keyboards left a lot to be desired in terms of build quality and feel. That’s when the Palm Portable Keyboard (PPK) caught his eye. It’s small enough to fold up and fit in a pocket, yet unfolds to a size big enough to feel comfortable while typing. Unfortunately, the version he preferred to use did not have either a Bluetooth or a USB interface, so he built up this Palm keyboard adapter.

The portable keyboards have a serial interface and custom connectors depending on the Palm model they were designed to connect to. [cy384]’s goal was to adapt the PPK as a generic USB HID keyboard using an Arduino Pro Mini clone, with a 3D printed adapter for both of the keyboard types that he had. The keyboards  use inverted TTL logic at 9600 baud with no parity and one stop bit. Some handshaking needs to be taken care of and there’s a low power mode that needs to be managed via the Arduino code. He was lucky to get his hands on a reference document that provided the hardware and software details to help him crack all of this. His Github repository has the code and 3D printable files for the adapters.