Pseudonymous maker “jefmer” has taken a compact keyboard equipment and turned it into a private digital assistant (PDA) — including standalone smarts and a pair of sunlight-readable reflective shows, proving its capabilities by writing the system’s software program on the system itself.
“I get pleasure from programming and get annoyed that tablets and laptops usually are not actually usable in direct daylight,” jefmer writes of the inspiration behind the mission, which takes as its inspiration pocket-friendly PDAs from the ’80s and ’90s. “The Pocket Pad prototype is my try to supply a small PDA like system that I can use within the nice outside. To this finish, I’ve mixed a PocketType miniature 40% keyboard with two very low energy [Sitronix] ST7302 monochrome shows and a Good!Nano nRF52840 primarily based controller board.”
This throwback gadget goals to ship a usable improvement setting in even the brightest of daylight. (📷: jefmer)
The keyboard is an off-the-shelf equipment, designed to place an ortholinear format in a particularly small area. Usually, a footprint on the bottom-left of the keyboard performs host to an Arduino Professional Micro-compatible microcontroller board that acts because the keyboard’s controller — however within the Pocket Pad’s case, this has been swapped out for a Good!Nano with a extra highly effective Nordic nRF52840.
Above the keyboard, jefmer has added a pair of compact 2.13″ 250×122 monochrome Sitronix ST7302 shows. “This show is much like a Sharp Reminiscence Show in that has no backlight and it permits a lot quicker updates than ePaper shows,” the maker explains. “In low energy mode with body refresh set to 4Hz, every show makes use of on common 30 microamps. It’s [also] versatile, in that, in excessive energy mode it could possibly replace at a 32Hz body price with present consumption nonetheless lower than 1 milliamp.”
The PDA contains help for notifications from each Apple and Android units. (📷: jefmer)
The software program for the PDA is written in Gordon Williams’ Espruino, a JavaScript port constructed for embedded microcontrollers. Whereas the show and keyboard drivers had been developed off-device, together with a textual content editor, the remainder of the gadget’s software program was developed on the Pocket Pad itself in a formidable feat of bootstrapping.
“The editor can open and edit the entire JavaScript recordsdata saved on the system,” jefmer explains. “In fact, which means it’s attainable to trigger a crash that may solely be repaired utilizing the WebIDE, nevertheless, it additionally means the system can be utilized to improve itself and repair issues on the fly. The editor makes use of the arrow keys to navigate and choose textual content, and helps the same old copy, minimize and paste operations.”
The gadget ought to run for as much as six months on a single battery cost, its creator estimates. (📷: jefmer)
Along with the editor, jefmer has written a clock utility, Bluetooth help for notifications from linked Android or iPhone units, and an app that enables it to behave as a Bluetooth keyboard for different computer systems. “For a future model,” the maker muses, “I can not resolve between a clamshell on the strains of a Psion PDA or a pill format which might be extra strong as hinge-less.”
The mission is documented in full on jefmer’s Hackaday.io web page; the supply code is obtainable on GitHub beneath an unspecified license, together with the maker’s different Espruino initiatives.
