only needs a Raspberry Pi single-board computer adding to the top in order to bring classic Amiga hardware bang up-to-date.
For anyone with an Amiga 500, Amiga 500 Plus, Amiga 2000, or another model and a willingness to work alongside the project's creator to iron out bugs and extend the number of platforms supported, the PiStorm is likely to prove a must-have add-on.
The PiStorm is designed to upgrade an Amiga — primarily the 500, 500 Plus, and 2000, though with the potential for other models and even alternative 68000-based machines in future updates, offering hope for those looking to take a classic Mac up a notch or two — at as low a cost as possible. The four-layer board itself is extremely simple, combining a few bus switches and flip-flops with an Intel Altera MAX II complex programmable logic device (CPLD) — plus pin headers, a regulator, and a few passives.
The CPLD is there to act as glue logic between the Amiga and a Raspberry Pi single-board computer which mates into the top of the PiStorm via its GPIO header. No other wiring is required: Just pop the 68000 out from the socket in the Amiga motherboard, insert the PiStorm in its place, add the Raspberry Pi and microSD card, and you're ready to start configuring your soon-to-be-much-faster Amiga.
The hardware is only part of the PiStorm, though. Switch your Amiga on, and you'll be presented with a blank screen. The secret to getting past this: Emulation. The PiStorm handles communication between the real Amiga hardware and the Musashi emulator, which then pretends to be a Motorola 68000 processor — or a 68010, 68020, 68030, 68040, and a small handful of other processor variants, with or without floating-point unit (FPU) coprocessor
There's still more: A keyboard and mouse connected to the Raspberry Pi's USB port can be passed through to the Amiga. A feature currently in development aims to bridge the Wi-Fi network on the Raspberry Pi with the Amiga, too, giving it network access which is indistinguishable from a native connection to any software you might run.
In short: The PiStorm is a one-stop shop for the overwhelming majority of upgrades a classic Amiga might
The PiStorm, and by extension the Raspberry Pi, is powered from the Amiga motherboard. When you switch the Amiga off, the Raspberry Pi loses its power without going through a safe shutdown process. You could mount the filesystem as read-only to avoid this, but then you won't be able to make use of the hard drive image support. There's also a noticeable delay in start-up, with the Raspberry Pi having to boot its operating system and load the emulator before the Amiga can start using it as a CPU.
More details on the project, plus all source code and hardware files, can be found on the PiStorm GitHub repository.