RISC OS users who were Acorn users long before the Archimedes and our favourite OS was ever a thing will remember that the BBC Micro had a younger, more limited sibling – the Acorn Electron. And they will also therefore have observed that the Raspberry Pi 400, a small computer built into a keyboard, could be seen as a nod to computers like the Electron – especially given that the Pi can run RISC OS, and therefore BBC BASIC (albeit a greatly improved version, and using much more memory), the language that we all used by default when first switching on the old 8-bit computer.
The Electron had a number of upgrades and add-ons available for it, one of which was the very popular Plus 1, an expansion unit that was the same width as the computer itself, and connected to the edge connector on its rear, and (if you squinted a
bit lot… okay closed your eyes and used your imagination) sort of made the Electron look a bit more like the BBC. The unit provided extra ports to connect things like printers to the computer, as well as cartridge slots to allow extra ROMs to be used, and so on.
Put those two things together – the keyboard-based Pi 400, and the old Plus 1 expansion pack for the Electron – and what do you get? Well, nothing, because they simply don’t go together. However, new from R-Comp is an expansion board for the Pi 400 (and the Pi 4) called the Plus One.
The headline feature of the add-on is that it allows you to add one (plus one, geddit?) extra OS to the computer in a way that makes it easy to switch between RISC OS and that other operating systems. A physical switch is provided to allow you to choose which OS to boot into when the computer is switched on, without needing to either rewrite critical files on your SD card (if you’re using just the one card), or to switch cards and then – if you’re anything like me – losing them.
A second feature of the Plus One is that it includes a real time clock (which is compatible with both RISC OS and Linux), with battery backup, which means the Pi 400 or Pi 4 will preserve the time from one session to the next.
The bare board version of the device costs £25.00 including VAT, and a cased version costs £30.00 – in both cases, you’ll be providing the operating systems yourself. OS bundles start from £65.00 (depending on the disc size you opt for) and packs bundled with a Pi 400 are available from £120.