Scorpion ZS-256 Turbo+

Manufacturer	Scorpion
Release date	1996 (1996)
Discontinued	2000 (2000)
Operating system	Sinclair BASIC, TR-DOS, CP/M and IS-DOS
CPU	Z80B @ 7.0 MHz
Memory	256 KiB
Storage	Hard drive
Removable storage	Floppy discs, cassette tape
Display	256x192
Sound	Beeper, AY-3-8912
Backward compatibility	ZX Spectrum 128

The Scorpion ZS-256 was a very widespread ZX Spectrum clone produced in St. Petersburg by Sergey Zonov (same person behind the "Leningrad" clone).^{[1][2][3][4][5]}

Introduced in 1991, it was fitted with a Zilog Z80B processor, a AY-3-8910 sound chip, whilst RAM memory options ranged from 256 to 1024 KB.^[6]

The computer was usually assembled in a mini tower configuration with a standard IBM power supply, allowing the connection of peripherals, drives, etc.^[7] Various expansions were produced, including SMUC – an adapter for IDE and ISA slots, which allowed the use of IBM PC compatible hard drives and expansion cards.^[8]

The Shadow Service Monitor (debugger) in the BASIC ROM was activated by pressing the Magic Button (NMI). There was also the option of fitting the machine with a ProfROM which included such software as a clock, hard disk utilities, and the ZX-Word text editor.^[9][10] The computer can work with TR-DOS, CP/M and IS-DOS systems.^[7]

In 1996, the Scorpion ZS-256 Turbo+ version was introduced, featuring a "turbo" mode (7 MHz instead of the original's 3.50 MHz), IDE Controller, CMOS, interrupt controller, ISA8 slot, as part of the SMUC expansion card., expansion board 101-key PC type keyboard, 3.5 floppy disc drive and a XTR modem (allowing access to ZX Net and FidoNet).^{[7][1][2][11][12]}

Extension kit Scorpion GMX (Graphic Memory eXpander) for Scorpion ZS-256 Turbo+, comes with 2MB of RAM and can emulate other clones like the Pentagon 128. It has new graphics modes: 640 x 200 with 16 colors; 80x25 character text mode.^[1]

Production of Spectrum-compatible computers ceased in 1998, with the Scorpion company focusing on the sale of IBM PC-compatibles and office equipment.

Versions

• Scorpion ZS-256 (1991)
• Scorpion ZS-256 Turbo+ (1996)
• Extension kit Scorpion GMX for Scorpion ZS-256 Turbo+ (1998)

Upgrades from the original ZX Spectrum 48/128K

• RAM 256 KB (GMX kit 2 MB)
• ROM 64 KB (GMX kit 512 KB);
• Additional GMX video modes: 640 x 200 with 16 colors; 80 x 25 character text mode.^[1]
• IDE Controller, CMOS, interrupt controller, ISA8 slot, as part of the SMUC expansion card.
• "Turbo Mode" that clocks the CPU up to 7 MHz
• Shadow Service Monitor (debugger) in ROM
• AY8910/12 sound chip
• Built-in printer interface (Centronics and RS232C);
• Expansion board IBM PC keyboard and mouse controller
• TR-DOS, CP/M and IS-DOS systems
• Built-in XTR modem (ZX Net, FidoNet)

References