BK-0010 Nostalgia page
This page is dedicated to two very popular Soviet home
microcomputers of the 1980's and most of the 1990's: Elektronika
and BK-0011M that had, unlike most home microcomputers in the USSR, not
an 8-bit CPU, but a 16-bit CPU with the PDP LSI-11 instruction
set. At the time of its debut it was several orders of magnitude
cheaper than an IBM PC or its Western clone.
Here are the main features of BK-0010:
- Production started in 1985, ended in 1993 or later
- 3 MHz clock, the manual claimed 300,000 op/sec; in reality a
register-register operation required 12 clock cycles
- 16-bit QBUS provided on a 64-pin 2-row DIN connector
- No peripherals in the configuration sold in stores; high schools
were supplied with a current loop adapter (19200 baud) to connect to a
classroom file server which usually was another Soviet PDP-11 clone - a
- 32 Kb RAM, out of which 16 Kb was either 512x256 black&white
or 256x256 4-color hardware-scrollable framebuffer; the colors were
Red, Green Blue, and Black
- For details on CPU, see PDP-11s
behind the Iron Curtain.
- Software character generator in ROM
- The ROM (almost 32 Kb) contained the BIOS (a keyboard driver, a
screen driver, a tape recorder driver, an 8x10 font) and a language
system; in the earlier model (BK-0010 proper) it was interpreted FOCAL,
so there was enough ROM left to put some hardware tests; in the later
model (Bk 0010.01) it was quite full-featured BASIC compiled into
P-code; it occupied almost all address space, getting into the 0176xxx
address range); this model was supplied with a cartridge containing the
original (0010) ROM.
- 12 Kb of the framebuffer could be blanked out to increase the RAM
available to the program to 28 Kb
- A tape recorder was used for file storage, the encoding used was
approx. 1200 bits/sec and not a very efficient or reliable one (pulse
width modulation with a strobe after every bit)
- No real-time clock interrupt, an undocumented programmable
clock register was found by the enthusiasts by blind trial and error
- A 16-bit universal parallel port provided on a 64-pin 2-row DIN
connector with an IRQ line
- There was a provision (two otherwise unused pins on the parallel
port, on some production runs - two points on the motherboard) and some
BIOS code) for a software-driven TTL-level serial connection with
speeds up to 9600 baud. The baud rates were not particularly accurate
(the claimed 9600 baud rate was not understood by other devices), but I
worked with an U.S.-made modem on 4800 baud.
BK-0011 has clock speed of 4 MHz, had 128 Kb of RAM (still, the
area above 0140000 was reserved for ROM), two frame buffer pages,
switchable color palettes (out of 16 predefined sets of 4 colors),
real-time clock interrupt, had ODT, better BASIC, and was able to run
an RT-11 class OS. The early BK-0010 model had a few hardware
bugs and was soon replaced with BK-0011M. A "HowTo" existed
describing how to convert BK-0011 to BK-0011M by replacing a few chips.
Thanks to the available QBUS connector and a parallel port, a
of peripherals have been adapted or developed to be used with BK-0010
and BK-0011M: printers, mice, joystics, Covox, sound synthesizers,
floppy and IDE controllers.
For a very long time it was believed that BK-0010, unlike most
home microcomputers, had no Western counterpart or prototype. Lately
learned that BK-0010 looks very much like a trimmed Terak 8510/a. I am
adapting my BK-0010/11 emulator to emulate Terak as well, using
whatever documentation is available on BitSavers. Boot
ROM contents are needed to do it right.
A fairly new snapshot of the emulator is here. There is no Terak
emulation yet, and it definitely is not a distribution. It uses SDL for graphics and native Linux
audio for sound and synchronisation, therefore it only compiles and
links under Linux. To compile, you will need the SDL development package.
If you have anything to send to me (clean Terak floppy images and
Terak ROM images are particularly welcome), please write (do not forget to
remove q's & x's). Thank you.
Useful links (in Russian only):
¿ Leonid A. Broukhis, 2004
This page has been accessed13355