🇷🇺 Elektronika K 001 DON (Электроника К 001 ДОН): Part 2 (Power On) [

Описание: Let's try powering on the DON ... TL;DW summary is it doesn't currently boot so some troubleshooting is required.

I've created a Github repository for this machine here:
https://github.com/BrettHallen/Elektr...

I'm temporarily using a Mean Well GP25A13A-R1B tri-voltage power supply as it has a 5-pin DIN output plug, but the DON's power socket is wired differently.

For the video output, the 5-pin DIN actually includes audio & video and I happen to have a ready-made cable that matches the pinout ... nice!

But it's not currently booting. It has just a single 2KB ROM containing the Loader which is used to bootstrap loading software via a tape (a Monitor program, BASIC, etc.). I have dumped it and compared with the original for the Специалист (Specialist) and there are a few bytes of difference.

There is also a diagnostic ROM available so I will try that as well ... perhaps one or more of the 16Kbit К565РУ3 DRAMs have failed?

00:15 ... Intro
01:50 ... ROMs
02:50 ... Temporary power wiring
04:40 ... Ready-made video cable
06:00 ... Power on (NOK)
08:28 ... Channel thanks & outro

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From Part 1:
Let's take a look at this Soviet computer construction kit (Набор "Конструктор" Персональной микро-ЭВМ) that was released in the late 1980s. It's based on the DIY Специалист (Specialist) computer design published in the Моделист Конструктор (Modelist Constructor) hobbyist magazine.

The Specialist had the following specs:
CPU: КР580ВМ80А (8080A) at 2MHz
RAM: 32 or 48KB
ROM: 2 to 12KB
Text: 64x25
Graphics: 384x256
Video: monochrome
Tape: 32bit/mm (about 1500 Baud?)

An excellent source for information about Soviet computers is here:
https://github.com/alemorf/retro_comp...

This particular kit was produced by the "Гранит" (Granite) concern located in Rostov-on-Don in Russia, hence the name of the computer I am assuming.

Unfortunately there is no documentation that I can find available online so the magazine articles will have to be my main source of information.

The top of the box says the following:
Набор "Конструктор" Персональной микро-ЭВМ

Набор-конструктор микро-ЭВМ:
1. Для сборки микро-ЭВМ;
2. Для ознакомления с устройством микро-ЭВМ;
3. Для ознакомления с основами компьютерной техники.

Собранная микро-ЭВМ:
1. Обучает по разным общеобразовательным и специальным программам;
2. Решает задачи в режиме программируемого калькулятора;
3. Реализует разнообразные программы интеллектуальных игр;
4. Хранит составленный Вами банк данных.

Which translates to:
Kit "Constructor" Personal Microcomputer

Microcomputer Constructor Kit:
1. For assembling a microcomputer;
2. For familiarising yourself with the structure of a microcomputer;
3. For familiarising yourself with the basics of computer technology.

Assembled microcomputer:
1. Provides training using various general education and specialised programs;
2. Solves problems in programmable calculator mode;
3. Runs a variety of intellectual game programs;
4. Stores the database you have created.

As it's an 8080-based machine it requires the standard tri-voltage power supply: ±5VDC and +12VDC via a 5-pin DIN socket.

Video output is probably baseband also via a 5-pin socket which includes also audio.

It also has a tape interface that uses, surprise, a 5-pin DIN - this is pretty standard across all Soviet machines.

I can see that this implementation has 32KB of DRAM in two banks of eight К565РУ3 (16K x 1-bit) with space for a third bank.

The Specialist was quite a popular design it seems - this is my first example as most have been variations of the Радио 86РК (Radio 86RK) design. The main difference, in my simple view, is that the 86RK was text only (using a version of the Intel 8275 CRT controller) whereas the Specialist was capable of graphics.
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