🇷🇺 MAGIC-06 ZX Spectrum Clone: Part 2 (Troubleshooting Begins) [TCE #0593]
30Let's see if this machine is working ... well, almost it seems. I managed to get it to boot and get a relatively stable RGB image ... really quite a bright white for a change.
But it seems that there's a keyboard problem ... booting with the МС7007 keyboard connected results in a screen with text "D BREAK - CONT repeats, 0:1" which I understand is the output you get if you stop a running program by pressing [N], [BREAK] or [STOP].
But ... I'm not running a program, just powering the machine on! Disconnecting the keyboard and powering on gets me to the expected boot screen, but reconnecting the cable has no effect ... apart from the [RESET] and [INV] keys which reset the machine and invert the video output respectively.
So I'm a bit stuck ... not sure how to proceed from here ... ?
00:00 ... Intro
02:00 ... Video output, but weird error message
02:40 ... [INV] button works!
03:25 ... Disconnecting keyboard then booting
04:00 ... Wear on the keyboard connectors
06:35 ... Silver painted keyboard connectors
07:30 ... Keyboard disassembly
09:10 ... The bloody, sticky [АР2] key
11:45 ... Keyboard membrane
12:15 ... I'm stuck - let's summarise
17:30 ... Channel thanks & outro
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From Part 1:
Let's have a look at this post-Soviet Sinclair ZX Spectrum clone utilising the Электроника МС7007 (Elektronika MS7007) keyboard. It was made by the "Magic Electronics Corporation" in Russia in late 1993.
Schematics & Magic-05 manual can be found on my Patreon here (public, no need to join):
https://www.patreon.com/posts/magic-05-magic-124329291
As with all Soviet/post-Soviet Speccy clones it has a full 64KBytes of RAM using the ubiquitous КР565РУ5Г 64k x 1bit DRAM. It's a late 1993/early 1994 build so uses a genuine Zilog Z80 CPU and a Western 27C257 EPROM (32KByte ... which is double what is needed for a Speccy), otherwise everything else looks to be Soviet-era parts.
I just realised ... they've switched to circular ceramic capacitors now instead of the square shaped ones with incredibly SHARP corners ... nice.
Interestingly it uses a more sophisticated БМК than I normally see ... this one is 100 pins (I think) and labelled "МЭДЖИК" (a transliteration of "MAGIC" into Cyrillic perhaps?). Usually we would see the square, 64-pin КА1515ХМ1-216 if they were using one to reduce chip count.
A БМК (Базовый Матричный Кристалл, or Basic Matrix Crystal) is similar to a Western Gate Array or ULA.
The Электроника МС7007 keyboard was used on other machines such as the Электроника МС0511:
• Электроника МС 0511 (Elektronika MS 0...
There's a little bit of info here:
https://speccy.info/Magic_(компьютер)
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https://karlcasey.bandcamp.com/
/ @whitebataudio