[[Image:symboscpcsymbos21cpc.gif|320px|thumb|320px|Screenshot of the SymbOS desktop running on the Amstrad CPC]][[Image:symbos-msxsymbos21msx.gif|320px|thumb|320px|SymbOS MSX running on a MSX2 computer; all applications are platform independant]] [[Image:symbos21pcw.gif|thumb|320px|SymbOS PCW is the third port to a different Z80 system and supports a screen resolution of 720x255]]
''Parts of this article have been copied from the [http://en.wikipedia.org/wiki/SymbOS english Wikipedia article].''
'''SymbOS''' is a free multitasking operating system for Z80 based 8-bit computer systems written by [[Prodatron|Prodatron]]. At present it is available for the computers of the Amstrad CPC as well as for all [[MSX ]] models starting from the MSX2 standard, all Amstrad [[PCW|PCW]] (Joyce) models until the PcW10 and the [[Enterprise]] 64/128. Contrary to early 8-bit operating systems it is based on a microkernel, which provides pre-emptive and priority oriented multitasking and manages RAM memory with a size of up to 576 1024 kBfor the executed applications. SymbOS contains a an MS-Windows like GUI, supports hard discs with a capacity of up to 128 GB 2 TB and can already be booted on an unexpanded Amstrad CPC-6128 or , a 128K-PCW, an MSX2or an Enterprise 128 with floppy disc drive.
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== History ==Already in the 80's, only few years after the release of the Commodore C64, the legendary [http://en.wikipedia.org/wiki/GEOS_%288-bit_operating_system%29 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 Already in 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 weren80't true operating systems with their own kernels, memory-management and so on. The only few years after the release of the [[Commodore 64]], the legendary [http://wwwen.prodatronwikipedia.netorg/detailswiki/GEOS_%288-bit_operating_system%29 GEOS] by Berkeley Softworks appeared and set the standard for a windows-based operating system on c64.htm?7 CEUS Desktop 2It was a graphical user-interface (GUI) which was similar to the old desktop of the Apple Macintosh.0 Powerfull applications were made available for GEOS like GeoWrite (1990similar to MS-Word)] by Prodatron or GeoCalc (similar to MS-Excel). It was just such incredible, that an extension8bit-machine with only 64K was able to realize such an operating system.
Therefore, On the Amstrad CPC's own OS (in combination with AmsDOS) and [[CP/M]] many efforts to build a decent GUI were the only two known OSes for the series, but the question remained: since made as well. In most CPCs have 128K cases they were just extensions to realize a WIMP (most C64 only have 64KWindows, Icons, Menus and Pointers), a screen-resolution of 320x200 environment but weren't true operating systems 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 multitaskingtheir own kernel, dynamic memory-management for up to 576K and a totaly MSso on. The [[CEUS Desktop 2.0|CEUS Desktop 2.0 (1990)]] by Prodatron was just such an extension-Windows-like GUI are the three most important featuressystem.
=== Events ===The following is Therefore, the CPC's own OS (in combination with AmsDOS) and [[CP/M|CP/M]] (plus) were the only two known OSes for the series, but the question remained: since most CPCs have 128K (most C64 only have 64K), a list screen-resolution of important events during 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 development-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 1024K and a totaly MS-Windows-like GUI are the three most important features.
* ''11/2000'': Development started* ''06/2001'': First preview of the desktop on the [[CPC Reunion 1]]* ''07/2001'': First screen shots in the internet, causing several rumours about a possible hoax* ''06/2002'': Second preview of the desktop on the [[CPC Reunion 2]]* ''09/2004'': SymbOS development has been continued after a break of three years* ''12/2004'': Full [[CPC IDE]] support implemented; preview of a harddisc based movie player, which used the SymbOS IDE/FAT routines* ''01/2005'': Release of the first official preview on the [[SymbOS Preview party]]* ''09/2005'': SymbOS development has been continued again* ''12/2005'': Full [[SYMBiFACE II]] support implemented* ''01/2006'': SymbOS is part of the [[CPC TREX]] startup system now* ''04/2006'': SymbOS release 1.0 is out* ''05/2006'': Development of the MSX version started<br>
=== Events ===
==Technical background==Even the Z80 8-bit CPU The following is able to run a pre-emptive multitasking environment. Missing mechanisms like memory protection, which are often called as a condition for multitasking, are system stability issues only. The MP/M operating system already proved, that multitasking on Z80 computers is possible, but it was not executable on home computerslist of important events during the SymbOS development.
While *''11/2000'': Development started *''06/2001'': First preview of the MOS Technology 6502 can not move the stack, desktop on the Z80 can freely replace it to any position [[CPC Reunion 1|CPC Reunion 1]] *''07/2001'': First screen shots in the memoryinternet, which is more or less causing several rumours about a condition for pre-emptive multitasking. The existance possible hoax *''06/2002'': Second preview of an alternative register set accelerates the content switching between desktop on the tasks dramatically. The restriction [[CPC Reunion 2|CPC Reunion 2]] *''09/2004'': SymbOS development has been continued after a break of three years *''12/2004'': Full [[CPC IDE|CPC IDE]] support implemented; preview of Z80 systems to a 64 kB address space can be solved with bank switching. In this way computers like harddisc based movie player, which used the Amstrad SymbOS IDE/FAT routines *''01/2005'': Release of the first official preview on the [[SymbOS Preview party|SymbOS Preview party]] *''09/2005'': SymbOS development has been continued again *''12/2005'': Full [[SYMBiFACE II|SYMBiFACE II]] support implemented *''01/2006'': SymbOS is part of the [[CPC TREX|CPC TREX]] startup system now *''04/2006'': SymbOS release 1.0 is out *''05/2006'': Development of the MSX version started *''12/2006'': SymbOS release 1.1 is out *''05/2007'': 1MB and richtext support together with the graphical browser [[SymZilla|SymZilla]] have been implemented *''07/2007'': Development of the [[PCW, MSX, |PCW]] version started *''08/2007'': SymbOS release 2.0 is out*''11/2012'': development continues*''08/2014'': SymbOS release 2.1 is out*''11/2014'': Development of the [[Enterprise or SAM Coupé are able to access hundred or thousand |Enterprise]] version started *''03/2015'': Development of kilobytes of memorynetwork support started *''08/2017'': SymbOS release 3.0 is out
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== Technical background == Even the Z80 8-bit CPU is able to run a pre-emptive multitasking environment. Missing mechanisms like memory protection, which are often called as a condition for multitasking, are system stability issues only. The MP/M operating system already proved, that multitasking on Z80 computers is possible. While the MOS Technology 6502 can not move the stack, the Z80 can freely replace it to any position in the memory, which is more or less a condition for pre-emptive multitasking. The existence of an alternative register set accelerates context switching between tasks dramatically. The restriction of Z80 systems to a 64 kB address space can be solved with bank switching. In this way computers like the Amstrad CPC and PCW, MSX, Enterprise or SAM Coupé are able to access hundreds or thousands of kilobytes of memory. <br> == Feature overview == *'''Micro kernel'''**Maximum amount of supported RAM: 576 1024 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 24 **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 2 TB**Maximum file size: 2 GB **Maximum number of devices: 8 **Maximum number of open files: 8 7 *'''Source code'''**Source code size (OS Release 12): ~ 3049.000 lines (1.5 MB) **Source code size (Applications): ~ 3470.000 lines (2.2 MB) **Total size of the Z80 source code: ~ 64119.000 lines(3.7 MB) *'''Supported platforms'''**Amstrad [[CPC|CPC]]-464, -664 and -6128 (unexpanded) and compatibles ([[CPC TREX|CPC TREX]], [[C-ONE|C-ONE]])**MSX2 with 128KB Ram (unexpanded) and compatibles (MSX2+, MSX TurboR, OCM)**Amstrad [[PCW|PCW]] (all models until PcW10) **[[Enterprise]] 64/128*'''Supported external hardware'''**[[Dk'tronics|dk'tronics]] memory expansion 64K-512K and compatibles ([[Dobbertin|Dobbertin]], [[SYMBiFACE II|SYMBiFACE II]], X-MEM)**[[SYMBiFACE II|SYMBiFACE II]] (realtime clock, ; PS/2 mouse, ; IDE interface, Ram/Rom expansion) and compatibles (X-MASS)**M4Board (ESP8266-based Wifi, SD card reader, Rom expansion)**HxC direct SD card access (FAT32)**Albireo (USB mouse)**MultiPlay (Amiga mouse)**[[AMX Mouse|AMX]] and [[Kempston Mouse|Kempston mouse]] (PCW)
**Sunrise IDE interface (MSX)
**MegaSD card interface for OCM, MegaflashRomSCC+SD (MSX)
**MP3MSX (MSX)
**DenYoNet (MSX; W5100-based Ethernet)
**GR8NET (MSX; SD card reader, W5100-based Ethernet)
**SE-ONE (MSX; MP3, FM Radio)
**Rookie Drive (MSX)
== Kernel ==
SymbOS includes a micro kernel, which takes over the fundamental tasks of an operating system. They are subdivided into the task management, the memory management, the banking management and the messaging.
=== Task management ===
For the task management a combination of pre-emptive and cooperative multitasking has been choosed, which makes different task priorities possible. Pre-emptive means that tasks are interrupted after a certain amount of time by the operating system, in order to share the CPU time with other tasks. Cooperatively means, that a task stops using CPU time by itself. It does it, if it finished its current job or is waiting for a certain event. Because of this combination it is possible to assign priorities. Tasks with a low priority receive CPU time only if all tasks with higher priorities are not currently working.
=== Memory and banking management ===
The memory management divides the entire RAM into small 256 byte blocks, which can be assigned dynamically. Applications are always running in a secondary 64 kB RAM bank, where no memory space is occupied by the operating system or the video memory. That makes it possible to reserve up to 63 kB in one piece.
The banking management makes sure, that the system is able to administer memory with a size of one megabyte even with the fact that the Z80 CPU has only a 16-bit address bus. It makes transparent access to memory and functions placed in other 64 kB banks possible.
=== Messaging ===
The communication between different tasks and the operating system usually does not take place via "Calls", but is done via "Messages". This is necessarily inside a multitasking environment to avoid organisation problems with the stack, global variables and shared system resources.
== Graphical user interface ==
The [[Graphical User Interface|GUI]] of SymbOS works completely object-oriented. Regarding the look and feel it is designed like MS windows. It contains the well-known task bar with the clock and the "start" menu and can open a big amount of windows, which can be shifted, resized and scrolled. As the complete system is written in optimized assembler, the speed of the GUI is only insignificantly under this of current systems and even faster than the original Amiga workbench.
The complete content of a window is defined with "controls". These are e.g. slider, check boxes, text lines, buttons or graphics. The background or not visible areas of a window don't need to be saved in a bit-map buffer. If an area is restored on the display, its content will just be redrawed. Because of this the SymbOS GUI works much more memory-friendlier than most other 8-bit GUIs.
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==Kernel==SymbOS includes a micro kernel, which takes over the fundamental tasks of an operating File system. They are subdivided into the task management, the memory management, the banking management and the messaging. ===Task management===For the task management a combination of pre-emptive and cooperative multitasking has been choosed, which makes different task priorities possible. Pre-emptive means that tasks are interrupted after a certain amount of time by the operating system, in order to share the CPU time with other tasks. Cooperatively means, that a task stops using CPU time by itself. It does it, if it finished its current job or is waiting for a certain event. Because of this combination it is possible to assign priorities. Tasks with a low priority receive CPU time only if all tasks with higher priorities are not currently working.
===Memory and banking management===The memory management divides SymbOS supports the entire RAM into small 256 byte blocksfile systems CP/M, which can be assigned dynamically. Applications are always running in a secondary 64 kB RAM bankAMSDOS, where no memory space is occupied by FAT12, FAT16 and FAT32 on all platforms. With the operating system or the video memorylast one SymbOS is able to address mass storage devices with a capacity of up to 128 GB. That makes it possible Also the ability to reserve administer files with a size of up to 63 kB in one piece2 GB is uncommon for an 8-bit system. Because of the FAT support data exchange with other computers is quite easy, as most 32 and 64 bit operating systems do support the three FAT file systems.
The banking management makes sure, that the system is able to administer memory with a size of more than half a megabyte even with the fact that the Z80 CPU has only a 16-bit address bus. It makes transparent access to memory and functions placed in other 64 kB banks possible.<br>
==Applications and executables =Messaging===The communication between different tasks and the operating system usually does not take place via "Calls", but is done via "Messages". This is necessarily inside a multitasking environment to avoid organisation problems with the stack, global variables and shared system resources.
There are several standard applications available for SymbOS, which have beend designed as clones of well known Windows and Macintosh programs. As an example these are applications similar to the Norton Commander (SymCommander), QuickTime (SymPlay), WinAmp (SymAmp) or Minesweeper.
==Graphical user interface==*'''Applications''' The GUI of SymbOS works completely object-oriented. Regarding the look **[[SymCommander|SymCommander]] (file and feel it is designed like MS windows. It contains the well-known task bar with the clock disc management) **[[SymZilla|SymZilla]] (browser and richtext viewer) **[[SymPlay|SymPlay]] (video player) **[[SymSee|SymSee]] (picture viewer) **[[SymAmp|SymAmp]] (jukebox music player) **Notepad (text editor)*'''Tools''' **[[SymSnap|SymSnap]] (emulator snapshot loader) **[[DiskDeDumper|DiskDeDumper]] (image to disc transfer) **[[Speech|Speech]] (voice synthesizer) **[[Pocket Calculator|Pocket Calculator]] (calculator) **[[SYMBiFACE II rom manager|SYMBiFACE II rom manager]] (rom management for the "start" menu [[SYMBiFACE II|SYMBiFACE II]]) **[[CPC TREX starter|CPC TREX starter]] (rom and can open a big amount of windows, which can be shifted, resized and scrolled. As disc image configuration for the complete system is [[CPC TREX|CPC TREX]]) *'''Games''' **[[Pac-Man for SymbOS|Pac-Man for SymbOS]] (game) **[[MineSweeper|MineSweeper]] (game) **[[Conways' Game of Life]] (simulator)**4-In-A-Row ([[SymStudio]] game written in optimized assembler, the speed of the GUI is only insignificantly under this of current systems SymBasic by EdoZ)**Tetris 2014 ([[SymStudio]] game written in SymBasic by EdoZ)*'''Demos and even faster than the original Amiga workbench.Screensavers''' **[[Diamonds|Diamonds]] (demo) **[[Starfield Simulation|Starfield Simulation]] (screensavers) *'''System programs''' **[[Control Panel|Control Panel]] (system configuration) **[[Task Manager|Task Manager]] (system monitor) **[[SymShell|SymShell]] (command line interface)
The complete content of a window is defined with "controls". These are e.g. slider, check boxes, text lines, buttons or graphics. The background or not visible areas of a window don't need to be saved in a bit-map buffer. If an area is restored on the display, its content will just be redrawed. Because of this the SymbOS GUI works much more memory-friendlier than most other 8-bit GUIs.<br>
=== SymStudio ===
==File system management==[[SymStudio|SymStudio]] is a Windows-based IDE (integrated development environment) by [[Trebmint|Trebmint]] for SymbOS supports the file systems CP/M, AMSDOS, FAT12, FAT16 and FAT32 on all platformssimiliar to MS Visual Studio. With the last one SymStudio makes it possible to develop SymbOS applications in Assembler or Basic ("SymBasic"). It is able also possible to address mass storage devices with a capacity of up to 128 GB. Also convert PC graphics and videos into the ability to administer SymbOS format ([[Format:SGX (SymbOS graphic files with )|SGX]], [[Format:VID (SymbOS video files)|VID]]). Have a size of up to 2 GB is uncommon look at [[SymStudio|its article]] for an 8-bit systemmore information. Because of the FAT support data exchange with other computers Currently there is quite easy, as most 32 and 64 bit operating systems do support the three FAT file systemsonly a beta version available.
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== Applications Porting and cross platform ability ==There are several standard applications available for SymbOS, which have beend designed as clones of well known Windows and Macintosh programs. As an example these are applications similar to the Norton Commander (SymCommander), QuickTime (SymPlay), WinAmp (SymAmp) or Minesweeper.
* '''Applications'''** [[SymCommander]] (file and disc management)** [[SymPlay]] (video player)** [[SymSee]] (picture viewer)** [[SymAmp]] (jukebox music player)* '''Tools and games'''** [[SymSnap]] (emulator snapshot loader)** [[DiskDeDumper]] (image to disc transfer)** [[Speech]] (voice synthesizer)** [[Pocket Calculator]] (calculator)** [[SYMBiFACE II rom manager]] (rom management SymbOS has been developed originally for the [[SYMBiFACE II]])** [[Amstrad CPC TREX starter]] (rom . Because of the modular structure with the strict separation of general and disc image configuration for hardware components the [[CPC TREX]])** [[MineSweeper]] (game)* '''System programs'''** [[Control Panel]] (system configuration)** [[Task Manager]] (system monitor)** [[SymShell]] (command line interface)porting to other Z80-based systems is quite easy.
=== SymStudio ===The MSX computers starting with the MSX2 standard are supported since summer 2006. The Amstrad [[SymStudioPCW|PCW]] port is a Windows-based IDE (integrated development environment) by available since August 2007. Since end of 2014 the port for the [[TrebmintEnterprise]] 64/128 has been done as well. Versions for SymbOS similiar to MS Visual Studio. SymStudio makes it Amstrad NC100/150/200 and PCW16, Spectrum Next and others are possible to develop SymbOS applications in Assembler or Basic ("SymBasic"). It is also possible to convert PC graphics and videos into , too, as they fulfill the requirements for SymbOS format (SGX, VID). Have a look at [[SymStudio|its article]] for more information. Currently there is only a beta version available.
By keeping a basic condition for an operating system, the strict separation of hardware and application software by the supply of an intermediate layer, SymbOS applications run platform-independently on each computer and do not have to be adapted for a special system. Exceptions are applications, which access directly the hardware.
==Porting and cross platform ability==SymbOS has been developed originally for the Amstrad CPC. Because of the modular structure with the strict separation of general and hardware components the porting to other Z80-based systems is quite easy.<br>
The MSX computers starting with the MSX2 standard are supported since summer 2006. Versions for the Enterprise 128, the Amstrad PCW and the SAM Coupé are possible, too, as they fulfill the requirements for SymbOS. By keeping a basic condition for an operating system, the strict separation of hardware and application software by the supply of an intermediate layer, SymbOS applications run platform-independently on each computer and do not have to be adapted for a special system. Exceptions are applications, which access directly the hardware.== Motivation ==
SymbOS was originally started as an experiment to find out, how far it is possible to implement a multitasking based operating system with a windows GUI on an 8-bit computer of 1985. Also GEOS contributed to the motivation, but the structure and features of SymbOS aren't similiar to this system. The release in 2006 proved, that such a "mini windows" is possible on a 20 years old home computer only with quantitative limitations. SymbOS is one of the largest retro computing software projects of the last years. One of the goals of the project is to copy in combination with various hardware extensions a complete PC job.
==Motivation==SymbOS was originally started as an experiment to find out, how far it is possible to implement a multitasking based operating system with a windows GUI on an 8-bit computer of 1985. Also GEOS contributed to the motivation, but the structure and features of SymbOS aren't similiar to these of these systems. The release in 2006 proved, that such a "mini windows" is possible on a 20 years old home computer only with quantitative limitations. SymbOS belongs to the largest retro computing software projects of the last years. One of the goal of the project is to copy in combination with various hardware extensions a complete PC job.<br>
== Web links ==
== Web links ==* [http://www.symbos.de SymbOS homepage]*[http://members.home.nl/evanzanten/msxorg/SymbOS%203%20install%20user%20and%20install%20guide.pdf SymbOS installation configuration manual (PDF)]* [http://groups.yahoo.com/group/symbos8bit SymbOS mailing list (new)]* [http://en.wikipedia.org/wiki/SymbOS english Wikipedia article]* [http://es.wikipedia.org/wiki/SymbOS spanish Wikipedia article]* [http://it.wikipedia.org/wiki/SymbOS italian Wikipedia article] *[http://ru.wikipedia.org/wiki/SymbOS russian Wikipedia article]* [http://cpcrulez.free.fr/applications_symbos_apply_preview.htm french information on CPCRulez]* [http://www.wacci.org.uk/magazine/137/137_03.html "New Generation - CPC Windows?"] ([[WACCI|WACCI]] article by [[ChaRleyTroniC|ChaRleyTroniC]])* [http://web.archive.org/web/20061116180805/http://www.snakeoillabs.com/2005/10/30/8-bit-guis-eye-candys-not-just-for-the-32-bit/ "8-Bit GUIs - Eye candy’s not just for the 32-bit!"] (Article)* [http://www.msx.org/forumtopicl6203.html Main thread on MSX.org] *[http://video.google.com/videoplay?docid=-6071242217428356949&q=symbos SymbOS presentation(Video) at RetroEuskal 2006]
[[Category:SymbOS| ]] [[Category:Operating_System]] [[Category:CPC_GUI]] [[Category:Extended RAM Software]] [[Category:PCW]]
