The Pentagon (Russian: Пентагон) home computer was a clone of the British-made Sinclair ZX Spectrum 128. It was manufactured by amateurs in the former Soviet Union, following freely distributable documentation. Its PCB was copied all over the ex-USSR in 1991-1996, which made it a widespread ZX Spectrum clone. The name "Pentagon" derives from the shape of the original PCB (Pentagon 48), with a diagonal cut in one of the corners.
Many simple devices (upgrades) were invented to connect to the Pentagon with some soldering.
Versions
- Pentagon 48K (1989 by Vladimir Drozdov)
- Pentagon 128K (1991)
- Pentagon 128K 2 (1991 by ATM)
- Pentagon 128K 3 (1993 by Solon)
- Pentagon 1024SL v1.x (2005 by Alex Zhabin)
- Pentagon-1024SL v2.x (2006 by Alex Zhabin)
- Pentagon ver.2.666 (2009 by Alex Zhabin)
The Pentagon 1024SL v2.3 included most of the upgrades of the standard Spectrum architecture, including 1024 KB RAM, Beta 128 Disk Interface and ZX-BUS slots (especially for IDE and General Sound cards). This model also featured a "turbo" mode (7 MHz instead of the original's 3.50 MHz).
Upgrades from the original ZX Spectrum
- Extra RAM ranging from 256 KB to 4 MB
- Several sound card possibilities such as Covox (usually named as SounDrive) or DMA UltraSound
- Additional video modes: 512x192 monochrome, 384x304, 256x192x15 (with no Attribute clash)
- CMOS with persistent real-time clock
- IDE Controller for hard drives
- "Turbo Mode" that clocks the CPU up to 7 MHz
References
External links
- Russian most popular Spectrum models Archived 2012-07-16 at the Wayback Machine
- Pentagon 1024 official site (in Russian)
- Schematic diagram of the Pentagon 48K and drive controller (DjVu)
- 128K Schematic diagram of the Pentagon (the DjVu)
- Schematic and wiring diagrams Pentagon 128K 1991, revised and enlarged version (PNG)
- Wiring diagram 128K the Pentagon (the PNG)
- NEW English FaceBook Group
