Pi-oneering Work in Mobile Computing

These days, the mobile computing space has been pretty well standardized — you can have any mobile device you want, as long as it is a smartphone, tablet, or a laptop. But in the earlier days of computing when the technology was just starting to come of age, particularly through the late 1990s and early 2000s, the mobile computing landscape was much more interesting (and sometimes weird). There were the PDAs like the PalmPilot and Apple Newton, and there were the ultra-mobile PCs (UMPCs) like the HP Jornada 720 and the Psion 5Mx, each designed to meet the diverse needs of their users.

It is hard to deny that today’s trio of mobile options are far superior technologically to the choices that were available in the past, but we have lost the imaginative form factors and user interfaces that kept us excited when new products were released. Software engineer and Hackaday.io user Icepat wanted to revive that excitement with a custom UMPC that blends the unusual with modern technology. The result was the Pocket Z, a pint-sized Linux computer with a physical keyboard that you can shove in your pocket like it’s 1999.

Pocket Z is powered by a Raspberry Pi Zero 2 W, so it has pretty decent performance for some casual hacking, but it will not approach even most smartphones in terms of raw power. A keyboard was built into a custom-designed PCB for use with a silicone membrane and keycaps. An ATmega32U4 microcontroller was included to handle processing inputs from the keyboard and to feed them into the Raspberry Pi via the USB-OTG port. There is no touchpad on the present device, but it may be added in a future revision.

A seven-inch 1024 x 600 pixel capacitive touchscreen display was also included in the Pocket Z. To reduce energy consumption and costs (the goal is to stay under $99), the display was directly wired into the Raspberry Pi’s GPIO pins. While this works well, it does use up all of the available pins, leaving nothing for additional accessories or hacking with. Power is supplied via a Li-Po battery.

For the OS, the Pocket Z uses a Raspberry Pi OS Lite installation that has been customized with XFCE and Conky. This is nothing earth-shattering, but it gets the job done and is efficient, which is critical for the relatively resource-constrained Raspberry Pi Zero 2 W. Naturally, one could use nearly any compatible OS that they choose, however, since the computer is powered by a stock Raspberry Pi with an off-the-shelf display and what is seen as a USB HID keyboard.

The Pocket Z may be a personal project at this point, but Icepat sees it as potentially more than that in the future. The computer is still under development, but Icepat is looking for feedback on this initial prototype. After collecting feedback from the community, the plan is to build another version of the device, likely also with a five-inch display option (which would happen to leave some GPIO pins open, as an added bonus). After that, if there is enough interest, Icepat hopes to mass produce the Pocket Z. Check out the project write-up and get your feedback in if you might like a modern UMPC tailored to your specifications.