Pentagon (computer)

The Pentagon (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. [1]

Pentagon-1024SL v1.x
Also known asПентагон
TypeHome computer
Release date1989; 32 years ago (1989)
Operating systemSinclair BASIC, TR-DOS
CPUКР1858ВМ1/3, Т34ВМ1, Z80A, B, H @ 3.5 MHz
Memory48 to 1024 KB

Many simple devices (upgrades) were invented to connect to the Pentagon with some soldering.[2]


  • 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)[3]

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).

Pentagon-1024SL v2.x

Upgrades from the original ZX SpectrumEdit


  1. ^ a b "Pentagon — SpeccyWiki".
  2. ^ "Russian Most Popular Spectrum Models". Archived from the original on 2012-07-16. Retrieved 2004-09-08.
  3. ^ "Информация".

External linksEdit