Amiga, PC or best of both?

Towards the end of the 80s, the PC was gaining ground with the MS-DOS operating system. Nearly every office became equipped with IBM PC compatible ATs (Intel 80286, -386 and -486). So what were you to do if you already had invested in the Amiga and didn’t want to spend a fortune on a PC?

The answer was turning your Amiga into a hybrid system, capable of running both PC and Amiga software. This was achieved by either running software emulation applications like Transformer, by using the Amiga Sidecar or by plugging in a bridge board into your Amiga, like the A2088 XT (i.e. the Janus card). The latter was the most popular and most successful, both on the front of running PC applications and running IBM compatible hardware.

The only downside was that at the moment of introduction, this Intel 8088 based board (running at 4.77 MHz with an 8-bit system bus) already seemed a bit outdated, as the PCs were sporting a whopping 10-16 MHz on a 16/32-bit AT bus. Next to that, the A2088 XT was slow compared to the Amiga itself, which itself ran at 7.14 MHz on the Motorola MC 68000 with a 16-bit bus. Some clever 3rd parties overcame this, by replacing the Intel 8088 with the NEC V20 CPU, running at 8 MHz, effectively doubling the XT side of your dual system, but still, it didn’t turn your Amiga into an AT compatible.

To effectively turn your Amiga into an AT PC, your needed to grab hold of the new A2286 AT board (OK, it wasn’t cheap at 1200 Euro, but you did get a 1,2 MB AT disk drive on top and it still was a lot cheaper than a PC).

This board consisted of an Intel 80286 CPU running at 8 MHz on a 16-bit system bus, 1014 KB of available RAM, 16 KB ROM BIOS, a socket for an optional 80287 mathematical co-processor and connectors for AT compatible hardware like disk drives. Next to that, it had a series of custom chips that made it possible for the PC to co-exist with your Amiga and 64 KB dual-port RAM, which basically allowed the PC world to write data to the Amiga world and vice-versa.

The custom chips also enabled you to connect a relatively cheap PC hard disk to the AT card, that could then hold both MS-DOS and Amiga partitions.

From a compatibility perspective, the card passed most of the tests with flying colors. Lotus 1-2-3, dBase III, Flight Simulator III, WP 4.x, … they all worked flawlessly.

Hardware like printers, hard disks, modems, … they all worked straight out of the box (most of the time, as sometimes you had to tinker a bit with the jumpers).

The bridge boards (most common for the Amiga 2000 but also for the 500 as can be seen from an old ad from the early 90s) could turn your Amiga into a powerful PC AT compatible, but still “be” an Amiga, allowing you to run the classic office software under MS-DOS, but have all the graphical firepower of the Amiga at your disposal, something the PCs would have to wait another 5 years (at least) for, to be on par with what the Amiga could deliver.

An old ad showing an XT-board for the Amige 500

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