This DIY Mechanical Keyboard Contains a Plethora of Exciting Features

I frequently extoll the virtues of mechanical keyboards because I truly believe that anyone who spends their day in front of a computer can benefit from the experience. A good mechanical keyboard can improve typing speed and accuracy while reducing repetitive stress injuries. Custom mechanical keyboards also give users access to all kinds of additional functions that improve productivity. Peng Zhihui’s HelloWord Keyboard takes that concept to the extreme with a plethora of exciting features.

Custom mechanical keyboards are a dime a dozen and we’ve featured dozens of examples. They all tend to combine beauty and function, with high-quality mechanical key switches and stylish key caps. The HelloWord Keyboard is no different. It has a stunning CNC-milled aluminum enclosure and compact 75% layout. But it is unique for a few reasons. The first is that it uses 74HC165 shift registers instead of a traditional keyboard matrix. That lets the STM32F103 microcontroller scan all of the keys at a high speed (twice per millisecond) and also prevents ghosting without the need for diodes. The STM32 also has granular control of every RGB LED underneath each individual key.

That hardware alone would make this keyboard worth your consideration, but it offers so much more. For example, there is a capacitive touch bar mounted in front of the space bar. That lets users perform quick actions with their thumbs — digits that are underutilized with conventional typing techniques. The touch bar acts as a 2D slider and is configurable for different actions. It can, for instance, copy when the user slides their thumb one way and then paste when they slide their thumb the other way.

But wait, there is more! HelloWord also contains a USB3 hub and an additional “dynamic module.” That module is swappable to support future designs, but Zhihui’s demonstration module is already amazing. It contains an e-ink screen, an OLED screen, two tactile buttons, and a special motorized control knob. That knob has a brushless DC motor for force feedback and active feedback. It can act has a dial for a variety of functions, with the motorized force feedback providing tactile clicks or resistance. It can also move on its own, such as to indicate volume level. Different “apps” are available to run on the dynamic module.

USB doesn’t provide enough power to drive that knob’s motor, so Zhihui found a clever workaround. An internal LiPo battery acts like a capacitor to store power for the motor until it is needed. The battery is always charging through USB, and then provides power for the motor when it needs to move.

The dynamic module has an additional USB port, so users can connect hardware like a fingerprint scanner or a wireless mouse dongle. Zhihui is a software developer and he programmed custom firmware for the HelloWord Keyboard along with an SDK for configuring all of the functions of the keyboard and the dynamic module. This project is open source and everything you need to build your own HelloWord Keyboard is on Zhihui’s GitHub page.