Atari ST GEM desktop

The Operating System (TOS) was the operating system of the Atari ST range of computers. This range included the 520ST, 1040ST and the F, FM and E variations (e.g.1040STE). Later, 32-bit machines (TT, Falcon030) were developed using a new version of TOS, called MultiTOS, which allowed multitasking. More recently, users have developed TOS further into FreeMiNT. Image File history File links Atari_tos_gem. ... Image File history File links Atari_tos_gem. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ... This article is about a corporate game company. ... The Atari ST is a home/personal computer that was commercially popular from 1985 to the early 1990s. ... The Atari TT030 is a 32-bit version of the 16-bit Atari ST family. ... The Atari Falcon030 The Atari Falcon was Ataris final computer product, more specifically named the Atari Falcon030 Computer System. ... MultiTOS was an improved version of TOS for the Atari personal computers. ... Multitasking may refer to any of the following: Computer multitasking - the apparent simultaneous performance of two or more tasks by a computers central processing unit. ... MiNT (MiNT is Now TOS) is an alternative operating system (OS) kernel for the Atari ST computer and its successors which is free software. ...

History

The CP/M operating system

When the first ST model was released back in 1985, Atari had developed an OS largely based on components already existing. The core of this new OS consisted to a great extent of CP/M, originally developed by Gary Kildall and often considered to be the first cross-platform operating system. Kildall had isolated the parts that addressed hardware directly and moved them into a module which he called the BIOS - the Basic Input/Output System. This ensured that the system could easily be adapted to new hardware platforms, without the need for major rewrites of the complete core of the OS. The 68k version of CP/M that Atari adapted for their ST range of computers is referred to as GEMDOS. The Atari GEMDOS comprise the highest level in TOS, while low level tasks are handed over to the BIOS as well as the XBIOS. The latter ran at an intermediate level where it includes routines that the OS needs internally, like managing interrupts and setting screen location. CP/M was an operating system originally created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc. ... Gary Arlen Kildall (May 19, 1942 – July 11, 1994) was an early American microcomputer entrepreneur who created the CP/M operating system and founded Digital Research, Inc. ... This article or section does not adequately cite its references or sources. ... In computing, an interrupt is an asynchronous signal from hardware or software indicating the need for attention. ...

GEM - The graphical user interface

Atari added a graphical user interface (GUI) to GEMDOS in form of GEM, short for Graphical Environment Manager. Originally developed by Kildall's company Digital Research, GEM in its turn consisted of 2 layers - the AES (Application Environment Service) and the VDI (Virtual Device Interface). While the VDI takes care of the actual blitting, drawing, plotting and filling, the AES is the highest level in GEM and as such provides functions to maintain window redraws and drawing of dialog boxes as well as evaluation of user input via the mouse and keyboard. The last ingredient of GEM was the GEM Desktop which in reality was nothing more than a GEM program itself. Via the GEM Desktop the user could now perform almost any task that any command-level operating system would allow, such as copying or deleting files and launching programs. Atari's version of this new, CP/M-based OS was given the name TOS - The Operating System. There have been suggestions that the acronym instead translated to "Tramiel Operating System", after Atari's boss at the time, but early Atari manuals did in fact make direct references to The Operating System. A graphical user interface (GUI, often pronounced gooey) is a type of user interface which allows people to interact with a computer and computer-controlled devices which employ graphical icons, visual indicators or special graphical elements called widgets, along with text labels or text navigation to represent the information and... GEM (Graphical Environment Manager) was a windowing system created by Digital Research, Inc. ... Digital Research, Inc. ...

TOS - A singletasking OS on chip

The early ST models loaded TOS 1.0 from floppy disk, but Atari soon after started supplying the ST with TOS on a ROM-chip. There were some clear advantages with this approach, and sure enough some disadvantages too. Loading the operating system from a ROM chip made the ST boot up very fast and also saved some precious memory, as the OS did not have to be loaded into RAM. However, with the OS in ROM there was no easy way to allow updates - the user had to get hold of a new TOS ROM-chip and physically replace the old one. Any bugs that might still be lurking in the operating system code would have to be cured by external hacks and patches. TOS was a single tasking operating system, in essence limiting the user to run only one application at a time. As a small exception to this rule there were desk accessories, small programs that were coded to be accessed via the GEM menu bar. While working in a GEM application one could have up to 6 desk accessories open concurrently. This solution in essence meant that TOS had support for a primitive kind of co-operative multitasking in GEM. As opposed to pre-emptive multitasking, which gives each process a regular "slice" of operating time, the co-operative mode means that while several processes might be running simultaneously only one of them can be active at a time. This might sound complex enough but since programs written for GEM need to return control back to the AES while being idle (waiting for user input), this multitasking mode works very well. If however a certain process would perform CPU intensive tasks or wait for user input, any other process would become un-accessible until that task was finished. A floppy disk is a data storage device that is composed of a disk of thin, flexible (floppy) magnetic storage medium encased in a square or rectangular plastic shell. ... Read-only memory (usually known by its acronym, ROM) is a class of storage media used in computers and other electronic devices. ...

Details

TOS combined Digital Research's GEM GUI running on top of the DOS-like GEMDOS. Features included a flat memory model, MS-DOS-compatible disk format, support for MIDI, and a variant of SCSI called ACSI (in later versions). One of the most interesting aspects of Atari's TOS was that it came on ROM chips, thus before local hard drives were available in home computers it was an almost instant-running OS. Instructions on how to use the directory command. ... In computer programming, the flat memory model is an approach to organizing memory address space. ... Microsofts disk operating system, MS-DOS, was Microsofts implementation of DOS, which was the first popular operating system for the IBM PC, and until recently, was widely used on the PC compatible platform. ... Musical Instrument Digital Interface, or MIDI, is a system designed to transmit information between electronic musical instruments. ... This article or section does not cite any references or sources. ...

TOS consisted of the following:

• Desktop - The main interface loaded after bootup.
• GEM - Graphical Environment Manager
  • AES - Application Environment Service
  • VDI - Virtual Device Interface (screen drivers only, other drivers loaded using GDOS)
• GEMDOS - GEM Disk Operating System
• BIOS - Basic Input/Output System
• XBIOS - Xtended BIOS
• Line-A - Low-level high-speed graphics calls. Obsolete

The following were extensions to TOS (loaded separately):

• GDOS - Graphics Device Operation System
• AHDI - Atari Hard Disk Interface (driver for Hard Drive)

Multitasking was not directly supported, TOS allowed desk accessories to be loaded into the system which were similar to TSR's (Terminate and Stay Resident) on PC's (up to a maximum of six). MultiTOS was developed to allow TOS to multitask. Terminate and Stay Resident (TSR) is a system call in DOS operating systems that returned control to the system as if the program had quit, but kept the program in memory. ... MultiTOS was an improved version of TOS for the Atari personal computers. ...

Desktop

Atari TOS/GEM - Monochrome screen

The TOS desktop used icons to represent files and devices, windows and dialog boxes to display info. The desktop file "DESKTOP.INF" was read to determine window settings, icon placements and drive icons, otherwise the standard default desktop of two floppy icons and the trash icon was used. screenshot Atari ST GEM (Desktop), made myself. ... screenshot Atari ST GEM (Desktop), made myself. ...

Later versions used "NEWDESK.INF" for saving and reading the desktop configuration.

Executable files were identified by their extensions: A filename extension is a suffix to the name of a computer file applied to show its format. ...

• *.ACC - Desktop accessory. Automatically loaded.
• *.APP - Application (not common).
• *.PRG - Executable program. Can be GEM programs.
• *.TOS - "TOS" program that didn't use GEM. The desktop cleared the screen, turned on the text cursor and hid the mouse cursor.
• *.TTP - "TOS takes parameters". This opened a dialog box where arguments could be added for the program. However, it converted characters to uppercase.

TOS programs (but not GEM programs) could autoboot by placing them in a folder named "AUTO". TOS 1.4 allowed GEM programs to be set to load automatically from the "Install Application" dialog. Programs with *.TTP extensions could not be used for autoboot. Desktop accessories were placed in the root directory of the default drive and loaded automatically. A blinking text cursor. ... A contemporary computer mouse, with the most common standard features — two buttons and a scroll-wheel. ... Example of dialog box from Microsoft Windows Dialog boxes are special windows which are used by computer programs or by the operating system to display information to the user, or to get a response if needed. ... A parameter is a variable which can be accepted by a subroutine. ... Capital letters or majuscules (in the Roman alphabet: A, B, C, ...) are one type of case in a writing system. ...

Versions

TOS 1

• 1.0 (ROM TOS) Earliest version released on disk. First ROM release of TOS.
  • Formats: floppy, 2 chip and 6 chip ROMs (192 KiB)
  • Rom date: 20 Nov 1985
  • Machines: 520ST, 1040ST
• 1.02 (MEGA TOS) fixed bugs, supported Blitter co-processor and real-time clock.
  • Formats: 2 chip and 6 chip ROMs (192 KiB)
  • Rom date: 22 Apr 1987
  • Machines: 520ST, 1040ST, Mega 2, Mega 4
• 1.04 (RAINBOW TOS) Many bug fixes, file selector changed, DOS-compatible disk formatting, much improved performance. However, compatibility problems with older software.
  • Formats: 2 chip and 6 chip ROMs (192 KiB)
  • Rom date: 6 Apr 1989
  • Machines: 520ST, 1040ST, Mega 2, Mega 4, Stacy
• 1.06 (STE TOS, Revision 1) Support for STe machines only. Needed STE_FIX.PRG to patch bugs.
  • Format: 2 chip ROMs (256 KiB)
  • Rom date: n/a
  • Machines: 520STE, 1040 STE
• 1.62 (STE TOS, Revision 2) bug fixes for the previous 1.06 STE TOS.
  • Format: 2 chip ROMs (256 KiB)
  • Rom date: 1 Jan 1990
  • Machines: 520STE, 1040 STE

According to the International Electrotechnical Commission a kibibyte (a contraction of kilo binary byte) is a unit of information or computer storage. ... A Blitter (acronym for BLock Image TransferrER) is a chip that specialises in bitmap data-transfer using bit blit methods. ...

TOS 2

• 2.02 Early TOS release for Mega STE.
• 2.05 (Mega STE TOS) Only found in the Mega STE with 720K floppy drive.
  • Format: 2 chip ROMs (256 KiB)
  • Rom date: n/a
  • Machines: Mega STE
• 2.06 (ST/STE TOS) Bug fixes, 1.44 MB disk support, memory test. Greatly enhanced GEM GUI. IDE hard disk booting. Last TOS version for ST/STE computers.
  • Format: 2 chip ROMs (256 KiB)
  • Rom date: 14 Nov 1991
  • Machines: 520ST, 1040ST, 520STE, 1040STE
• 2.07 used on the Falcon prototype "FX-1"
• 2.08 used in notebook ST.

TOS 3

• 3.01, 3.05, 3.06 (TT TOS) Primarily for 68030 TT support only.
  • Format: 4 chip ROMs (512 KiB)

TOS 4

TOS 4.92 (German)

• 4.00, 4.01, 4.02, 4.04 (512 KiB) Update for Falcon 030 machines only.
• 4.92 Last TOS version, was never released

Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ...

See also

• EmuTOS
• Multitasking versions of TOS
  • MiNT
  • MultiTOS

EmuTOS is a replacement for TOS (the operating system of the Atari ST and its successors), released as free software. ... MiNT (MiNT is Now TOS) is an alternative operating system (OS) kernel for the Atari ST computer and its successors which is free software. ... MultiTOS was an improved version of TOS for the Atari personal computers. ...

External links

• Town's Guide to TOS Revisions
• TOS/MiNT emulator
• Atari ST System Disks
• TOS 2.06 Guide - User's guide
• Atari Compendium - Reference guide for Atari ST programming. Recommended
• GEM based site

	Preceding:	GEM
	Subsequent:	EmuTOS,MiNT,MultiTOS