Acorn Electron Guide
Category: Acorn Computers — Last updated: June 2025
The Acorn Electron was a budget home computer launched by Acorn Computers in August 1983, intended as a low-cost alternative to the BBC Micro for home users. It used the same 6502A processor and a subset of BBC BASIC, making it highly compatible with BBC Micro software while hitting a lower price point.
Specifications
| Feature | Detail |
|---|---|
| CPU | MOS 6502A at 2 MHz (effective speed lower due to ULA contention) |
| RAM | 32 KB |
| ROM | 32 KB (BBC BASIC + OS) |
| Video modes | Modes 0–6 (subset of BBC Micro modes) |
| Sound | Single square wave channel + noise |
| Storage | Cassette; expansion modules for disc |
| Launched | August 1983 |
| Launch price | £199 |
The ULA bottleneck
The Electron used a single custom ULA chip for memory management, video, and I/O, which caused significant CPU stall in many video modes as the ULA could not service both the CPU and video simultaneously. This made some BBC Micro software run noticeably slower on the Electron — particularly games and applications that used the higher-resolution graphics modes.
Expansion & Plus 1
The Electron’s rear expansion port allowed a range of add-ons including the Plus 1 (ROM cartridge slots + Centronics port), the Plus 3 (3.5″ disc drive), and various third-party interfaces. Several manufacturers produced disc systems that significantly expanded the machine’s capabilities. The cartridge slot is particularly interesting as it provides an easy way to add ROM-based software without soldering.
3D-printed accessories
I design and produce several 3D-printed accessories for the Electron, including cartridge shells for the Plus 1 and various bracket and mounting solutions. Browse the Acorn Electron section of the shop for what’s currently available.
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