Soviet computer UT-88. The history.

I want to start my blog with this computer. I’m going to make a replica of this computer using FPGA. But let’s start with its history first.

UT-88 is a hobbyist 8-bit computer built on CPU KR580VM80A, a Soviet analog of a famous Intel 8080. Schematics and a detailed description were published in a popular Soviet magazine for kids, “Young Technician”, in 1989.

This computer was not particularly popular because other computers with better specifications were available then. The main reason for the publication of “Young Technician” was to allow building a computer for young people. This computer had to be very easy to make, containing only easily accessible components that could be built block by block with easy debugging of each unit.

In the minimal configuration, this computer had only a power supply unit, a CPU unit, and a memory unit with a small amount of memory. It is also required an interface unit that contains six 7-segment indicators and a 17-key keyboard to enter hex data.

A display and extended memory units were added to the complete configuration. The display unit provided the opportunity to use a standard TV set as a computer display. A Full-size keyboard was connected to the unit as well. With the extended memory unit, the computer had 64k of RAM and up to 256k of “RAM-disk”, which could be used by OS CP/M that was adapted for it.

Specifications:

Minimum configuration:

CPU: KR580VM80A (Intel 8080)

Memory: RAM – 1k, ROM 1k

Output: six 7-segment indicators

Input: 17-key keyboard

External memory: tape recorder

Full configuration:

Memory: RAM – 64k, video RAM – 1k, ROM – 2k, “RAM-disk” – 256k

Output: TV set, b/w text mode only, 64×28 characters (5×7 dots each).

Input: 59-keys keyboard