π«π· Matra Alice: Part 2 (Keyboard Problem) [TCE #0568]
26The replacement keyboard screws (M2x6 pan head) finally arrived ... but there are still problems with the keyboard. Some keys don't work at all, some keys do work fine and some others print the whole row of keys.
00:00 ... Intro
01:50 ... Matra Alice expansions
05:08 ... 50 Quid
06:20 ... Testing the keyboard
12:17 ... Checking the key switches
13:10 ... Engineer SS-03 solder sucker
16:50 ... Key switch closeup
18:15 ... Replacing the keyboard cables & plugs
21:49 ... Upgraded keyboard cables
24:20 ... Keyboard issue visualised
29:14 ... CPU ports checked with logic analyser
37:16 ... Channel thanks & outro
Oh, and look what I found:
https://github.com/Fred72z/ALICE
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From Part 1:
This boldly red computer is a French version of the Tandy MC-10 using the same Motorola 6803 CPU clocked at 890KHz and using the same MC6847 Video Display Generator (VDG). It was built by French companies Matra and Hachette but seems to be commonly known simply as the "Matra Alice".
The main difference, apart from the bold colour and AZERTY keyboard layout, is the RGB video output (via a 7-pin DIN) rather than RF modulated video ... yay!
The video pinout is:
Pin 1 = n/c
Pin 2 = ground
Pin 3 = red
Pin 4 = synch
Pin 5 = green
Pin 6 = audio
Pin 7 = blue
After building the video cable and supplying 10VDC, I got an image which was quite unstable. I noticed a variable resistor (R45) in the video output stage so gave it a tweak ... perfect, almost! This R45 looks to adjust the level of the FS (field synch) and HS (horizontal synch) signals coming out of the MC6487 VDG, which makes sense why it resolved the stability problem.
The keyboard wasn't working properly ... looks likely due to a mechanical issue ... missing screws! Whilst I have it apart I might as well give the case & key caps a good wash before reassembling with some replacement screws.
Then it'll be time to try loading some cassette software. I'm assuming I'll need the 16KB RAM expansion to play any modern software.
And I'm assuming that it should run Tandy MC-10 software ... although key mapping might be an issue due to the differences in the English QWERTY and French AZERTY layouts ...
I guess this machine could easily be converted to a bog-standard Tandy MC-10 by rearranging the keys and replacing the ROM ... a bright red MC-10 with built-in RGB video output ... but then it'd lose a lot of its charm!
This page (in French) looks to have some quite good information about the Alice series of computers:
https://alice.system-cfg.com/about.php
There were further versions ... this first one (same as the Tandy MC-10) is also known as the "Alice 4KB". The Alice 32 was next with 16KB of RAM and using a different video chip, then the Alice 90 with a proper keyboard & more memory, then finally the Alice 8000 that had both a Motorola 6803 and an Intel 8088.
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