Commodore PC10-III

Coming soon
The tired old PC10-III

Commodore might have made their fortune with calculators, VIC20s and Commodore 64s, but in the late 80s the Amiga had come along and even with a wonderkind in your product lineup, there's always that one client demanding something IBM compatible. So they let the German engineers loose on the project and lo, the Commodore PC family was born.

These machines are very strange. They have MOS specific chipset parts, NEC and AMD CPUs, oddball hard disk interfaces... they share a lot of infrastructure with the Amiga bridgeboards too. Heck, most these machines have a dedicated port labelled MOUSE that is indeed an Amiga joystick port in disguise. Other fun features are adjustable clock frequency via keyboard shortcuts on the fly... handy for old games that don't want to play nice.

This specific example is a PC10-III, a Turbo XT system. It has the same nifty little chassis as the PC40-III 286 variants. It featured a factory 20MB XTA hard disk drive, a Chinon 5.25" floppy drive, built-in CGA graphics, an 10MHz Siemens-sourced 8088 and 640K RAM onboard.

Specifications

Siemens 8088 @ 10MHz (selectable 4.77, 7.16 or 9.54MHz)

Faraday FE2000 "chipset"

640KB RAM

20MB Western Digital WD93028-X XTA hard disk

Paradise CGA graphics

3Com Etherlink II ethernet adapter

MS-DOS 3.30

Unique features

The MOS "Frankenmouse" mouse port controller which converts Microsoft Bus Mouse signals into Amiga mouse signals is pretty slick, the variable frequency tomfoolery works a treat too. It allegedly exposes mono video from an RCA jack on the rear, though my example currently doesn't run to test that.

The PC10/20-III range is kind of interesting in that Commodore, ever the frugal folk, leveraged their design work across the family - the PC10/20-III is architecturally identical to the Amiga A2088 bridgeboard, and the hard disk subsystem is why the Amiga A590 hard disk drive (and the A2091... though often without the header fitted) was shipped with the WD93028-X - Commodore were buying pallets of 20MB drives and using them across the whole family. The A590/2091 also featured SCSI which keeps them significantly easier to keep alive but the PC10/20? Without another drive controller you're kinda doomed.

Personal history

My first PC10-IIIs were given to me by a family friend when I was all of 16 years old. Those machines were all dead, nothing I did was bringing any of them back (I didn't know enough then!) and so they waited... one ended up getting the big chop to become THE PC10-III, my custom HTPC after many iterations... it might even get its own page one day.

My current example was from an eWaste auction in Dunedin. $1.00, with a Commodore-branded amber monitor. When I got it, bugger me if it just worked - no issues. But it didn't take long... maybe fifteen minutes before the WD93028-X did what they do best... locked up hard and never spun again, just like the three others I'd had before it.

I have tried to run my one since then just without the drive... no go. It's not battery damage, I snipped it out long ago. So something in the FE2000 chipset has shit the bed I suspect.

I'm uncertain how to proceed with it at this stage... on one hand, it deserves life. But on the other... what's it offer us? The PC40-III and Jenny cover all the early DOS stuff more than amply, the PC10-III gives us... 4.77MHz and CGA, but in a form that's hard to work with - XT keyboard, so that needs adapted... CGA video so that also needs adapted... 1352 style quadtrature mouse, so another Amiga to PS/2 adapter required... and we still have to solve for missing XTA hard disk, preferably without stuffing an XT-IDE in, I'd rather use its original adapter if we can.

Perhaps the right move would be building a little bridge card that carries an RGB2HDMI type implementation to get CGA to VGA, and does XT to AT-PS/2 and Quad to PS/2 at the same time... Hmmmmm...