"Single-Chip Computer" ELLO 1A Offers Through-Hole or Surface Mount Assembly and a C Interpreter

Unusual vintage-inspired computer, powered by a Microchip PIC32MX, drops BASIC in favor of an interpreted C environment.

Gareth Halfacree
3 years agoRetro Tech

Pseudonymous engineer "KnivD" has released the source code and schematics for a "true single-chip computer" based on the Microchip PIC32 — and boasting the unusual feature of an interpreted C programming environment.

"ELLO 1A is a PIC32-based system, one of the simplest possible realisations of a fully functional computer with graphics, sound, I/O, and storage," KnivD explains of the project. "Although built from only 25 components, it offers a good educational overview of what a typical computing system consists of. It can also make a good and inexpensive, yet interesting hobby computing project."

"The focus is away from competing with the big guns, such as Raspberry and the likes, but rather an alternative option to enjoy building and programming a small and very unpretentious computing system, entirely from scratch."

Inspired by the classic eight-bit computers of yesteryear the ELLO 1A, which is powered by a Microchip PIC32MX microcontroller, boots directly into an interpreted programming environment — but where its predecessors may have chosen BASIC, FORTRAN, or FORTH, ELLO 1A goes in a very different direction: C.

"In my view and with the full respect to BASIC, which was my first, just like to many others, C is the one truly 'universal' programming language, and worthy to be learnt by anyone who wants to have a closer contact with programming," KinvD explains of the reason behind the move, which takes what is traditionally a compiled language and retools it for interactive interpreted use. "It is the de-facto 'The Language' in the modern computing world, especially in the modern embedded computing world."

"C is also much more 'unsafe' language with significantly lower tolerance for errors than BASIC or other alternatives, especially when working with direct access to the memory and the other hardware resources. While that might sound scary, it is also beneficial for the user to learn and work without having an error net which saves them from mistakes otherwise. Teaching careful programming and awareness of the system resources can do only good to any programmer."

The ELLO 1A itself uses an interesting dual-mode circuit board design, which offers through-hole technology (THT) for ease of assembly if you're unfamiliar with soldering or surface-mount technology (SMT) if you'd prefer. "I designed the ELLO to be simplest," KinvD says, "yet built from atomic components only" - just 25 parts in total, in fact.

More details about the ELLO 1A can be found on the project website, while bare circuit boards are available for sale on Tindie at $5 each. The schematic, bill of materials, assembly drawing, and Gerbers can be downloaded from the official website; the source code, meanwhile, has been uploaded to GitHub under the permissive Apache 2.0 license.

Gareth Halfacree
Freelance journalist, technical author, hacker, tinkerer, erstwhile sysadmin. For hire: freelance@halfacree.co.uk.
Latest articles
Sponsored articles
Related articles
Latest articles
Read more
Related articles