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Last modified on 8 August 2006, at 15:22

SymbOS

Revision as of 15:22, 8 August 2006 by Prodatron (Talk | contribs) (resized images)

Screenshot of the SymbOS desktop running on the Amstrad CPC
File:Symbos-msx.gif
SymbOS MSX running on a MSX2 computer; all applications are platform independant

Introduction

Already in the 80's, only few years after the release of the Commodore C64, the legendary GEOS by Berkeley Softworks appeared and set the standard for a windows-based operating system on c64. It was a graphical user-interface (GUI) which was similar to the old desktop of the Apple Macintosh. Powerfull applications were made available for GEOS like GeoWrite (similar to MS-Word) or GeoCalc (similar to MS-Excel). It was incredible, that an 8bit-machine with only 64K was able to realize such an operating system!

On the Amstrad CPC many efforts to build a decent GUI were made as well. In most cases they were just extensions to realize a WIMP (Windows, Icons, Menus and Pointers) environment but weren't true operating systems with their own kernel, memory-management and so on. The CEUS Desktop 2.0 (1990) by Prodatron was just such an extension-system.

Therefore, the CPC's own OS (in combination with AmsDOS) and CP/M were the only two known OSes for the series, but the question remained: since most CPCs have 128K (most C64 only have 64K), a screen-resolution of 320x200 with 4 colours (C64 only has 2 colours for each 8x8 area in 320x200) and some more advantages, why not have something similar? So the SymbOS-Project was born. SymbOS stands for "SYmbiosis Multitasking Based Operating System". SymbOS is a demonstration of what has been achieved on the CPC: real preemptive multitasking, dynamic memory-management for up to 576K and a totaly MS-Windows-like GUI are the three most important features.

SymbOS started being developed by Prodatron in November 2000 (more details on the development needed)

Features

  • Micro kernel
    • Maximum amount of supported RAM: 576 KB
    • Maximum number of processes 32
    • Number of different process priorities 9
    • Maximum number of timers 32
    • Maximum number of open messages 64
  • System manager
    • Maximum number of applications 16
    • Maximum application core size 63 KB
  • Desktop manager
    • Maximum number of windows 32
    • Maximum number of controls per window 1000
    • Maximum possible screen resolution 16.000 x 16.000 pixel
  • File manager
    • Maximum hard disc size 128 GB
    • Maximum file size 2 GB
    • Maximum number of devices 8
    • Maximum number of open files 8
  • Source code
    • Source code size (OS Release 1) ~ 30.000 lines
    • Source code size (Applications) ~ 34.000 lines
    • Total size of the Z80 source code ~ 64.000 lines

Applications

Web links