Topic - Russian ZX: the history of the creation of the Russian Spectrum.

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(C) Igor Kostrikin
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   The first experiments to create domestic
The original ZX dates back to 1987. The first
"Moscow"became a mass model (1988),
being the most complete clone.
At the same time, Baltika appeared,in which there was
fewer cases due to the use of K556PT4 and
K155PE3. The machine turned out to be less compatible
mine because of the original circuit design and
higher processor clock speed (4
MHz).
 The following year, 1989, production began
"Moscow-128" (a fairly accurate copy Sin-
clair-128),this model had an interface
printer, programmable joystick, TV-RGB
output and system connector, but there was no music
cal processor and disk controllerYes.
   The cheapest and most popular model was
"Leningrad-1"(1989). To increase co-
capacity of which numerous skilled
we had to eliminate various simplifications
schemes. The only additional device is
The thing in this car is a joystick.
   Simultaneously with "Leningrad" on the market
appeared"Pentagon-48",named so because
-for the pentagonal wiring of the earth bus along
circuit board outline. For the first time, as I became
standard device, there was a Beta Disk inter-
face (on the same board with the computer). Scheme
this car was somewhat reminiscent of"Moscow-
-128", and, accordingly, there were similar
disadvantages, in addition, there was no formation
TV-RGB and system connector, but use
used an improved reading scheme with
tape recorder.
   Somewhat later, "Red-
gorsk" (1990), in which for the formation
For the TV signal, ROM K573RF2(5) was used.
In terms of mass popularity, this model could not exceed
zoiti "Leningrad-1".
 In 1991, such a representation was born
tel of the Spectrum family, like "Leningrad-
-2". Compared to its predecessor,
Addressing of the Kempston joystick has been corrected, you
external bus introduced, significantly modified
printed circuit board. Not particularly widespread
received.
   At the same time, a rather unusual
Sinclair's version - "ZX-Profi". This machine,
First of all, it is distinguished by the amount of RAM (up to 1
Mb),except for the usual modes 48 and 128 Kb,
There is an opportunity to work in SR/M. For this
extended graphics are provided (512x240,
I don’t remember how many colors) and text mode
(80 characters per line), there are full
new parallel and serial ports,
music processor, IBM keyboard controller
viatures, turbocharged. In later
There is a hard drive controller in there. By now
Several versions have been released recently
"Profi". The SR/M system gives access to nor-
small implementations of languages such as Pas-
cal, C, function libraries, linkers, re-
doctors and databases.
   "Pentagon-128" -one year old "Leningrad-
-2" and "Profi". He, perhaps, is still
is the most popular model among
systems with extended memory, despite
a huge number of disadvantages (complexity of
widening, not a very successful mixture "Pentago-
on-48" and "Moscow-128").
 Briefly about some other models...
   "Scorpion ZS-256". First of all, 256 Kb
RAM, full system connector, music
cal coprocessor, Centronics interfaces
and RS-232, Turbo mode. On new versions
machine installed PROF-ROM with some
useful programs: Honey - Commander,
MagOS (allows you to store several
to tasks and switch between them), dis-
kovy utilities. It is theoretically possible to work
that in SR/M. Additional devices: available
There is a MIDI interface, universal con-
SMUC peripheral roller, IBM keyboard controller
viature, which is also the Kem-interface
pston-Mouse (allows you to use AT and
XT keyboards, passive and active mice).
   "The Hobbit". RAM - 64 K, ROM - 64 K, Russian
fixed 88-key keyboard, 8
function keys, programmable
user, 2 screens (2nd screen buffer).
The 2nd screen can be used as a shadow
RAM (not cleared during RESET). There are 3 modes
ma keyboard operation, cancel autostart
programs, micromonitor and other useful
functions. Local network support available
from ROM. Depending on the modification it may
present disk drive controller (TR-
-DOS, CP/M), music coprocessor. B
Basic commands for deleting a group have been added
strings and string search, there is an alternative
programming language (most often LOGO).
 "Elara-Disk-128". Configuration: system-
ny block,remote 58-key keyboard
tour, Sinclair and Kempston joysticks,
Lprint-3, music processor, built-in
speaker, system connector and several
Incorrect port decryption.

                "Quorum".

   "Quorum-64" - RAM 48 K, shadow RAM 16 K,
88 keys, SR/M.
   "Quorum-128" - everything that the model 64 K +
+ expanded to 128 K memory, built-in
tests, monitor, copier, SR/M loader,
TR-DOS.
   "Quorum-128+" - like the previous model
+ built-in 3.5" drive

   "ZX-Next". This model in "ZX-Forum 2"
predicted a great future, but time
passed, but no progress this unit
didn't call. Key Differences: Usage
another Z80 as a video processor,
slot architecture, several identical
system connectors for expansions, soft
requirements for the microcircuits used
wrinkle, lockadditional ports for
compatibility with older programs, half-
valuable port #FF, RS232 port, TURBO mode,
additional graphics mode 640*200
(with CGA addressing), RAM up to 512 K, control
IBM keyboard controller, hard drive controller
IDE, SETUP with configuration memory,
LAN controller (10 Mbaud) and unit
power supply with the possibility of external activation
and shutdown.
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