I recently discovered an all-in-one magic goodie for PCs from the eighties from the USA: The PicoMem board by FreddyV.1 This ISA bus plug-in card2 provides RAM, hard disc, floppy disc, sound card, USB, Bluetooth and even a network for old PCs. Just the idea that I would be able to connect my Schneider Euro-PC3 to the Internet or its predecessor4 left me excited. At a price of just under 60 USD, I bought it immediately (note: customs duties for shipping to Europe will be added).
This is how the little gadget looks like: Nomen est Omen: An 8-bit ISA plug-in card with some memory and a Raspberry Pico W.5 This is where all the ‘magic’ happens. A Linux with DOSBox6 emulates the various plug-in cards and controllers in software and ‘injects’ everything back to the ISA bus. It obtains its ISO images from the SD card, which it integrates as bootable hard disks and floppy drives. Base-Memory,7 XMS8 and EMS9 and even the Wifi module of the Raspberry Pico W are emulated and looped through as well. As an NE200010 compatible network card, the latter is integrated into DOS and is made accessible with the aid of the mTCP11 TCP/IP tools.
The result is a kind of chimera12 of old and new hard- and software. A truly impressive concept and engineering achievement.
The software is completely open-source and lovingly maintained by FreddyV in a (unfortunately GitHub) Git repo.13 However, simply plugging it in and getting started is not that easy. Knowledge of the old concepts, such as how IRQs and memory addresses work, everything about MS-DOS and its free derivative FreeDOS,14 is all a prerequisite.
In my experience, there was a small glitch: connected to the Euro-PC, the picoMem still required an external power supply via USB as well as a second of ‘thinking time’ before switching it on, so that the BIOS can recognise the memory and the drives.15 However, the picoMem board is constantly being improved and with each new firmware version it gets a little better.
A Schneider Euro-PC with only one ISA interface by default is the ideal machine for exactly this board. Up to now, I have solved the lack of free ISA slots not very elegantly with a triple extender board. Lo-Tec XTIDE,16 1MB memory card17 and a VGA card for connecting a modern monitor were plugged into a kind of horizontal riser card extending out of the chassis. The MM12 amber monitor has its own connector, to which no modern monitor can be connected. This plug-in card zoo is not a pretty sight, even with a 3D-printed frame around it.
Now I’m thinking about moving VGA and the small picoMem into the internal housing, which would require a small 2-way ISA riser card with flexible cable routing. The long winter is still ahead of me.
In the meantime, I have been able to fulfil my long-cherished wish. The installation of my beloved Geoworks Ensemble18 in version 2.0, which was the superior graphical user interface for IBM-compatible PCs at that time and which attracted the interest of both Apple and Microsoft, who wanted to buy it up. Largely programmed in assembler, it was able to magically create a graphical Motif UI even on the less powerful XTs. In combination with high-resolution 720×348 Hercules graphics19 and a complete office suite consisting of Geowrite, Geodraw and Geocalc, it set standards at the time. It still lives on today as an open-source graphical add-on for retro computers.20
Video im AV1-Format. Wenn Sie es nicht sehen, nutzen Sie einen Browser/App (noch) ohne AV1-Unterstützung.
I was never able to install it on the Euro-PC because of the 512 KB RAM and the lack of money for a 20 MB hard drive. It wasn’t until a few years later in the early 1990s that I was able to do so on a Vobis Highscreen 386DX with 25 Mhz.
With this in mind,
Your Tomas Jakobs