ZX-NEXT

By popular demand, I present the corporate description of the subj.

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The ZXNEXT PC is an original development of the "SLOT" enterprise.
The PC is based on a "motherboard" board (dimensions 150x186 mm),
with the ability to install up to 4 (5) system connectors on it.
This allows you to easily expand the system. In the basic In this variant, the board
is a complete PC of minimal configuration
similar to the ZX Spectrum computer. When developing the ZXNEXT PC
the main attention was paid to full software compatibility
and reliability. At the same time, the PC architecture is the most flexible
among machines of this class. The problem of connecting
peripheral devices and additional controllers is completely solved.
Use of a second Z80 as a video processor (ULA), made it possible to:
completely abandon the selection of components. By halving the time
of RAM regeneration (1ms), reduce the requirements for the used memory chips (RU5/7 with any letters and in any combination). Receive
a standard television signal (lowercase and vertical blanking,
inserts, additionally: separate vertical and horizontal signals synchronization). Maintain all timing relationships (INT 8.5mks; SYNH 64mks; synchronized FLASH; 312 lines per frame). The above
has had a beneficial effect on video effects in many games. The
unpleasant flickering has disappeared(ARKANOID2;CHASE HQ;RAMBO3 and others).
The correct geometry of “curb” effects is formed (MONTEKARLO;
JAWS and others).
The presence and correct implementation of the #FF port (ARKANOID1;
SHORT2;TOP GUN; RENEGADE1 and others will work). Correct port addressing
KEMPSTON JOSTICK #DF (and not #1F !) - the manipulator will work in the programs
ATLANT1,2;ANTARES;NONAMED;HOSTAGES;NAVY1,2 and others. All this allows
to talk about REALLY FULL COMPATIBILITY.
Among the positive aspects of the ZXNEXT PC it should be noted the presence of
an RGB driver on the main board, the ability to buffer the keyboard,
easy expansion of RAM and ROM, the use of only common
chips.
Controllers have been developed especially for the ZXNEXT PC:
1.TR-DOS + non-maskable RAM. Compared to similar ones, the main characteristics have been significantly
improved. A two-phase PLL is used.
Two precompensation times have been introduced for recording 125/250 ns. Hardware
access time has been reduced (200 ms instead of the standard 600ms). The presence of
an additional port of non-maskable RAM allows you to load other
DOS versions instead of ROM.
2. RAM expansion up to 128K + music coprocessor + RS232 + MIDI.
Any AY8910/12 can be used. Availability of RESET DOS from 128K.
Standard (12V) RS232, supported in proprietary Sinclair 128 ROM.
3.TURBO+CENTRONIX+real time clock+graphics mode640x200 (CGA).
In TURBO mode, performance increases from RAM to 1.76 from ROM to 2.0.
Software control of the transition to TURBO. The CENTRONIX port has the ability
to support the IRPR protocol. Non-volatile RAM, calendar, timer and
real time clock. Additional graphics mode 640x200 CGA
monochrome 2 colors from a palette of 15 (25 lines of 80 characters 8 * 8 pixels).
4. IBM/PS/XT keyboards. Fully emulates the standard keyboard
ZX Spectrum, additional modes are possible.
5.Switching power supply.Designed specifically for ZXNEXT: +5V 5A;
+12V 2A.
6.SECAM encoder.Allows you to connect a color TV via the LF input,
record an image to a VCR, use a PC in
cable studios television.
7.Expansion of RAM up to 512K.Allows flexible use of RAM for various
purposes. For example, simultaneously loading up to three games for
ZX-SPECTRUM 128K under IS-DOS and entering/exiting them into the system and back.
8.Hard disk controller. Has high operating speed, compatible
with any hard drives of the IDE standard. Does not have the disadvantages
characteristic of similar controllers.

Preparing for release: (document 1995 - my note)
1.Universal programmer.
2.MODEM + AOH.
3.High-speed local network controller.
4.Video adapter EGA/VGA.
5.TR-DOS controller supporting HIGH DENSITY mode.

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Still availableschematic and descriptive documentation about 20 sheets.
Offered by the manufacturer in varying degrees of readiness:
from a set of printed circuit boards complete with flashed ROMs (3 pieces) + disk
with 5.25' drivers to a ready-made configured device.
I chose the first option. The impressions are very good (and I saw
in work and assembled/configured/repaired almost everything Soviet emulators ZX SPECTRUM.
Sincerely, Sergey Mukhachev.

Greetings, dear Sergey!

One day, namely Wednesday November 19, 1997 16:27, a certain humanoid calling himself
Sergey Mukhachev wrote something intelligible to the name All:
SM> graphic mode 640x200 CGA monochrome 2 colors from a palette of 15
SM> (25 lines of 80 characters 8*8 pixel)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I wonder if this is a text mode or a graphic mode?

Regards Andrey Mihaylow

AM> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AM> I wonder if this is like a text mode or a graphic mode?

This is CGA! With the ensuing consequences.

AM> Sincerely, Andrey Mihaylow

All the best. /──────────────────────\ [ Fantasy World - Rulez ]
Sincerely, │ Wanderer 'Sagacious' │ [ Getting up early - Must Die]
─────────────────── ────\──────────────────────/ [ Station 106.8 - Rulez ]
...Don't be too wise, but be wise in moderation...