maandag 19 september 2016

CPC464

The Amstrad / Schneider CPC464. Again a perfect, though quite lengthy story on The Register about the origin and creation of this machine.
 It's a Z80 based computer with a built-in cassette-recorder. Quite amazing for it's time. The one I bought from eBay is in a reasonable condition. Its got some bumps and scratches and it definitely needs a good cleaning.


It came without a manual, but this is available at the CPCWiki.

dinsdag 6 september 2016

Thomson MO5

This one was advertised on eBay as 'ORDINATEUR THOMSON MO5 EN LOOSE'. Yes, it came from France. While collecting several types of computers from the eighties I slowly realised that every country has it's own history of retro computing.In the UK it's mainly Acorn and Sinclair, Germany was mostly Commodore minded, TRS-80 and Apple in the States. And in the Netherlands we had a mix of all of these, plus some additional Philips computers like the P2000.
But France it was slightly different. As the French government needed a computer to be used in schools they obviously wanted to have a French product. So Thomson hastily produced the MO5, which had to compete with the ZX-Spectrum and Commodore 64. But it was actually already outdated when it was released so they were mainly sold to schools. In large quantities I presume, because they are not very rare on eBay. Almost none have found their way to other countries, most likely because they were only produced with an AZerty keyboard.

For me there are a few challenges. First it came without any accessory, so I'll have to find a 17VDC power supply and a connection cord for the cassette recorder. And it only has a fixed SCART cable so that somehow has to be connected to a monitor.
Extra challenging is that the most detailed information is only available in French, which is not my best language...

Connecting the monitor.

The MO5 comes with a fixed SCART (or 'Péritélévision ' as it is called in France) cable. Although it's not used much nowadays, the standard is still quite common.
Connections are as follows (from Wikipedia):

Pin Name Description

1 AOR Audio Out Right

2 AIR Audio In Right

3 AOL Audio Out Left + Mono

4 AGND Audio Ground

5 B GND RGB Blue Ground

6 AIL Audio In Left + Mono

7 B RGB Blue In

8 SWTCH Audio/RGB switch / 16:9

9 G GND RGB Green Ground

10 CLKOUT Data 2: Clockpulse Out (Unavailable ??)

11 G RGB Green In

12 DATA Data 1: Data Out (Unavailable ??)

13 R GND RGB Red Ground

14 DATAGND Data Ground

15 R RGB Red In

16 BLNK Blanking Signal

17 VGND Composite Video Ground

18 BLNKGND Blanking Signal Ground

19 VOUT Composite Video Out

20 VIN Composite Video In 

21 SHIELD Ground/Shield (Chassis)

 But that does not tell me which outputs are actually supported . Looking for 'Video signal MO5' does not get me anywhere, but after googling 'signaux video MO5' I finally found 'Christophers's lair', a site with some technical information.
From this I can conclude that the unit will support RGB output, something that I can easily interface to my GBS8200 converter.

Power

The only label on the unit says 'Power Supply 17VDC'. It's not clear what the tolerance or power consumption is. The technical manual contains a diagram of the (very basic..) power circuit:

The circuit shows that the this 15 or 17 VDC is not very critical at all, and I actually think it would work fine on 12 V. What is important here though is that the power jack has ground on  the centre and positive voltage on the outside, something that is not very common in standard power supplies.


Price [Original] €25,- [€541,-]
Processor Motorola 6809E @ 1MHz
RAM 16KB
ROM 32KB
Programming Microsoft Basic
Why ? The first French computer in my collection.