keyboard

443 Articles

Breaking Down The USB Keyboard Interface With Old-Fashioned Pen And Paper

June 24, 2021 by 37 Comments

What is better for gaming, old PS/2 style keyboards, or modern USB devices? [Ben Eater] sets out to answer this question, but along the way he ends up breaking down the entire USB keyboard interface.

It turns out that PS/2 and USB are very, very different. A PS/2 keyboard sends your keystroke every time you press a key, as long as it has power. A USB keyboard is more polite, it won’t send your keystrokes to the PC until it asks for them.

To help us make sense of USB’s more complicated transactions, [Ben] prints out the oscilloscope trace of a USB exchange between a PC and keyboard and deciphers it using just a pen and the USB specification. We were surprised to see that USB D+ and D- lines are not just a differential pair but also have more complicated signaling behavior. To investigate how USB handles multi-key rollover, [Ben] even borrowed a fancy oscilloscope that automatically decodes the USB data packets.

It turns out that newer isn’t always better—the cheap low-speed USB keyboard [Ben] tested is much slower than his trusty PS/2 model, and even a much nicer keyboard that uses the faster full-speed USB protocol is still only just about as fast as PS/2.

If you’d like to delve deeper into keyboard protocols, check out [Ben]’s guide to the PS/2 keyboard interface, complete with a breadboarded hardware decoder. If these keyboards have too many keys for your taste, you might consider this USB Morse code keyboard. Thanks to Peter Martin for the Tip!

A Tidy Octave Mod For The Casio SK-1

June 17, 2021 by 5 Comments

1985 saw the release of the Casio SK-1, a compact sampling keyboard that brought the technology to a lower price point than ever before. However, one drawback of this was that it comes stock with only a 2.5 octave keyboard. [Jonas Karlsson] wanted a little more range out of the instrument, so set about hacking in his own octave mod.

The build consists of fiddling with the SK-1’s microprocessor clock to change the pitch of the notes generated by the instrument. The original clock is generated by a simple LC circuit, which in this mod is fed to an inverter, and then a pair of flip-flops to divide the clock by four. The original clock and the divided version are then both sent to a mux chip. With the flick of the switch, either the original or downshifted clock can be sent to the microprocessor.

With the slower clock feeding the microprocessor, all the notes are downshifted an octave. The resulting sound, which you can listen to on Soundcloud, is similar to what you get when chopping down sample rates. It bears noting, however, that as this mod changes the master clock, other features such as rhythms are also effected.

It’s a great mod which gives the instrument a gloomier, grittier sound on demand. The Casio SK-1 has long been prized for its hackability; we’ve seen them completely worked over in previous mods. If you’ve got your own twisted audio experiments cooking up in the workshop, be sure to drop us a line.

The Ridiculous GameCube Keyboard Controller Gets Modded

June 17, 2021 by 4 Comments

Believe it or not, there was a keyboard peripheral sold for the original GameCube, and it was built into the middle of a controller. Designed for the Phantasy Star Online games, it allowed players to easily communicate with others via chat. [peachewire] got their hands on one, and set about modifying it in the way only a true keyboard fanatic could.

The result is a gloriously colorful keyboard and controller set up to work with a PC. The stock membrane keyboard was removed entirely, which is possible without interfering with the gamepad hardware inside the controller shell. It was replaced with a Preonic keyboard PCB, fitted with Lubed Glorious Panda switches and those wonderful pastel DSA Vilebloom keycaps. The keyboard also features a Durock screw-in stabilizer to make sure the  space key has a nice smooth action. The controller itself received a set of colored buttons to match the theme, setting off the aesthetic. It’s still fully functional, and can be used with an adapter to play games on the attached PC.

Overall, it’s a tidy controller casemod and one hell of a conversation starter when the crew are scoping out your battlestation. The added weight might make it a little straining for long gaming sessions in controller mode, but it looks so pretty we’re sure we wouldn’t notice.

We’ve seen keyboards and Nintendo mashed up before; this Smash Bros. controller makes excellent use of high quality keyswitches. Video after the break.

Continue reading “The Ridiculous GameCube Keyboard Controller Gets Modded” →

Tiny Mechanical Keyboard, Powered By Pi Pico

June 9, 2021 by 18 Comments

For some applications, smaller is better and that is precisely the thinking behind a diminutive keyboard like the PiPi Gherkin, which is designed to use the Raspberry Pi Pico as its controller. This keyboard may have only 30 keys in total, but they are full-sized for comfort and don’t let the scant layout mislead you. It has more functionality than it would seem to at first glance; the entire bottom row acts as dual function tap/hold keys, allowing the keyboard to shift layers on the fly.

This keyboard definitely has a a thoughtful layout, and we’re not just talking about the tap/shift functionality. We especially like the way the Pi Pico is tucked neatly underneath the main PCB, taking up very little room while exposing its USB connector between two standoffs for easy access without requiring an adapter, or wiring a separate plug.

If the Gherkin sounds familiar, we’ve seen it before as part of this lunchbox cyberdeck build, where the small size allowed it to take up impressively little room. The shifting might take a little getting used to, but it’s a clean design that uses full sized keys, so when it comes to small keyboards one could certainly do worse.

Miss The Predictive Text From Your Old Nokia? Build Your Own T9 Keypad

June 3, 2021 by 23 Comments

Do you miss the mind-blowing typing speed of your old Nokia brick with predictive text turned on? Well, so did [Guy Dupont], so he created a USB keypad with T9 predictive text built-in to turn typing into a one-handed affair. Video after the break.

T9 was the first predictive text technology to gain widespread use in the late ’90s and early 2000s. The goal was to minimize the number of keypresses required for typing on multi-press keypads by matching key sequences to a dictionary of the possible words. It prioritizes words based on the frequency of use and can adapt to user preferences. [Guy] implemented T9 in Circuit Python, mainly for the RP2040 microcontroller used on the Raspberry Pi Pico, which will appear as a normal USB keyboard when plugged into any device. The dictionary is stored in the flash memory and can be updated using a tool also created by [Guy]. It can also change modes for old multi-press typing, numeric pad, or macro pad.

We would be interested to see just how fast it’s possible to type one handed with T9, and what application our readers can imagine. It doesn’t look like this implementation can learn the user’s preferences, which we think would be a worthy feature to add.

We’ve covered several unique custom keyboards recently, some more practical than others. On the silly side, these include a grenade-shaped function pad, a five-button chording keyboard, and a tiny two-key keyboard. Continue reading “Miss The Predictive Text From Your Old Nokia? Build Your Own T9 Keypad” →

Custom Macro Keyboard Looks Good In Wood

May 21, 2021 by 5 Comments

There’s more than one way to make a mechanical macro pad, and this wooden wonder represents one of our favorites. [Tauno Erik] had an old rubber dome rectangle keyboard lying around that still worked, but the poor thing was missing some of its caps. After salvaging the controller, [Tauno Erik] got to work on the tedious task of figuring out the mapping of the matrix, which was made easier with a Python script.

Almost every component of this beauty is wood, including the mounting plate and those thicc and lovely keycaps — their top layer is solid oak, and the bottom bit is birch plywood. In order to interface the ‘caps with the switches, [Tauno Erik] designed and printed connector pieces that sit inside the extra large keycaps and accept the stems of the key switches.

Speaking of switches, we’re not sure if [Tauno Erik] ended up using Cherry green switches, browns, or a mix of both (that would be interesting), but each one is mounted on a custom PCB along with a diode and a pull-up resistor. You can see more build pictures at [Tauno Erik]’s site, and stick around for a visual tour of the completed build after the break.

Wood is a great choice for keycaps, and we imagine they’ll only look better with age and use. A more common use for wood on a keyboard build is in surprisingly comfortable wrist rests.

The Keyboard You Really Don’t Need Or Want

May 6, 2021 by 48 Comments

Most people think of a keyboard as a flat, vaguely rectangular thing with around 100ish different keys. A mechanical keyboard enthusiast would heartily disagree and point out various tenkeyless, 75%, 60%, or 40% keyboards that strip down the idea of what a keyboard is by taking keys out. [Stavros Korokithakis] takes that notion and turns it on its side by creating the five-button vertical keyboard known as Keyyyyyyyys.

This keyboard, or keystick, is designed to be onehanded and to be eye-contact-free. With just five keys, it makes heavy use of chording to output all the characters needed. It has a maximum of 32 possible states and taking out pressing nothing as a no-op leaves 31 possible key combinations. So [Stavros] had to get creative and laid out the letters according to their frequency in the English language. The brains of Keyyyyyyyys is the ubiquitous ESP32, emulating a Bluetooth keyboard while being wrapped in a simple 3d printed box. The code is hosted on GitLab.

If you don’t know how hard it is to learn a five-key chording keyboard from scratch, definitely check out [Stavros]’ video embedded below. “C’mon h.” We have heard reports that you can learn these things, though.

While this five-button keyboard may seem small, this two-button keyboard still has it beat by three keys. A one-button keyboard is just a morse code keyboard, and we are looking forward to a wireless Bluetooth version. Continue reading “The Keyboard You Really Don’t Need Or Want” →