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Virtual file system

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A virtual file system ( VFS ) or virtual filesystem switch is an abstract layer on top of a more concrete file system . The purpose of a VFS is to allow client applications to access different types of concrete file systems in a uniform way. A VFS can, for example, be used to access local and network storage devices transparently without the client application noticing the difference. It can be used to bridge the differences in Windows , classic Mac OS / macOS and Unix filesystems, so that applications can access files on local file systems of those types without having to know what type of file system they are accessing.

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81-425: A VFS specifies an interface (or a "contract") between the kernel and a concrete file system. Therefore, it is easy to add support for new file system types to the kernel simply by fulfilling the contract. The terms of the contract might change incompatibly from release to release, which would require that concrete file system support be recompiled, and possibly modified before recompilation, to allow it to work with

162-444: A dummy implementation may be used to allow development to progress before the final implementation is available. In another case, a fake or mock implementation may be substituted during testing. Such stub implementations are replaced by real code later in the development process. Usually, a method defined in an interface contains no code and thus cannot itself be called; it must be implemented by non-abstract code to be run when it

243-404: A touchscreen , can both send and receive data through the interface, while others such as a mouse or microphone may only provide an interface to send data to a given system. Hardware interfaces exist in many components, such as the various buses , storage devices , other I/O devices, etc. A hardware interface is described by the mechanical, electrical, and logical signals at the interface and

324-583: A 6-bit volume control per channel. The analog output is connected to a low-pass filter, which filters out high-frequency aliasing when the Amiga is using a lower sampling rate (see Nyquist frequency ). The brightness of the Amiga's power LED is used to indicate the status of the Amiga's low-pass filter. The filter is active when the LED is at normal brightness, and deactivated when dimmed (or off on older A500 Amigas). On Amiga 1000 (and first Amiga 500 and Amiga 2000 model),

405-406: A 68k (a 68040 or 68060) and a PowerPC (603 or 604) CPU, which are able to run the two CPUs at the same time and share the system memory. The PowerPC CPU on PowerUP boards is usually used as a coprocessor for heavy computations; a powerful CPU is needed to run MAME for example, but even decoding JPEG pictures and MP3 audio was considered heavy computation at the time. It is also possible to ignore

486-480: A Boolean toggle state can be left clicked whilst the menu is kept open with the right button, which allows the user – for example – to set some selected text to bold, underline and italics in one visit to the menus. The mouse plugs into one of two Atari joystick ports used for joysticks , game paddles , and graphics tablets . Although compatible with analog joysticks , Atari-style digital joysticks became standard. Unusually, two independent mice can be connected to

567-472: A PowerPC native microkernel and software. Later Amiga clones featured PowerPC processors only. The custom chipset at the core of the Amiga design appeared in three distinct generations, with a large degree of backward-compatibility. The Original Chip Set (OCS) appeared with the launch of the A1000 in 1985. OCS was eventually followed by the modestly improved Enhanced Chip Set (ECS) in 1990 and finally by

648-415: A new game platform. Kaplan hired Miner to run the hardware side of the newly formed company, "Hi-Toro". The system was code-named "Lorraine" in keeping with Miner's policy of giving systems female names, in this case the company president's wife, Lorraine Morse. When Kaplan left the company late in 1982, Miner was promoted to head engineer and the company relaunched as Amiga Corporation. The Amiga hardware

729-621: A new release of the operating system; or the supplier of the operating system might make only backward-compatible changes to the contract, so that concrete file system support built for a given release of the operating system would work with future versions of the operating system. One of the first virtual file system mechanisms on Unix-like systems was introduced by Sun Microsystems in SunOS 2.0 in 1985. It allowed Unix system calls to access local UFS file systems and remote NFS file systems transparently. For this reason, Unix vendors who licensed

810-589: A number of years afterwards. The original model is one of a number of mid-1980s computers with 16- or 16/32-bit processors, 256 KB or more of RAM, mouse-based GUIs, and significantly improved graphics and audio compared to previous 8-bit systems. These systems include the Atari ST —released earlier the same year—as well as the Macintosh and Acorn Archimedes . Based on the Motorola 68000 microprocessor ,

891-519: A predecessor to Blender . Poor marketing and the failure of later models to repeat the technological advances of the first systems resulted in Commodore quickly losing market share to the rapidly dropping prices of IBM PC compatibles (which gained 256 color graphics in 1987), as well as the fourth generation of video game consoles . Commodore ultimately went bankrupt in April 1994 after a version of

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972-401: A programming style called programming to the interface . The idea behind this approach is to base programming logic on the interfaces of the objects used, rather than on internal implementation details. Programming to the interface reduces dependency on implementation specifics and makes code more reusable. Pushing this idea to the extreme, inversion of control leaves the context to inject

1053-503: A series of technical upgrades known as the ECS and AGA , which added higher resolution displays among many other improvements and simplifications. The Amiga line sold an estimated 4,910,000 machines over its lifetime. The machines were most popular in the UK and Germany, with about 1.5 million sold in each country, and sales in the high hundreds of thousands in other European nations. The machine

1134-443: A set of libraries . The software libraries may include software tools to adjust resolution , screen colors, pointers and screenmodes. The standard Intuition interface is limited to display depths of 8 bits , while RTG makes it possible to handle higher depths like 24-bits . The sound chip, named Paula, supports four PCM sound channels (two for the left speaker and two for the right) with 8-bit resolution for each channel and

1215-434: A software module A is deliberately defined separately from the implementation of that module. The latter contains the actual code of the procedures and methods described in the interface, as well as other "private" variables, procedures, etc. Another software module B , for example the client to A , that interacts with A is forced to do so only through the published interface. One practical advantage of this arrangement

1296-485: Is called a hardfile . UAE could also treat a directory on the host filesystem ( Windows , Linux , macOS , AmigaOS ) as an Amiga filesystem. Interface (computing) In computing, an interface is a shared boundary across which two or more separate components of a computer system exchange information. The exchange can be between software , computer hardware , peripheral devices , humans , and combinations of these. Some computer hardware devices, such as

1377-460: Is invoked. An interface called " Stack " might define two methods: push() and pop() . It can be implemented in different ways, for example, FastStack and GenericStack —the first being fast, working with a data structure of fixed size, and the second using a data structure that can be resized, but at the cost of somewhat lower speed. Though interfaces can contain many methods, they may contain only one or even none at all. For example,

1458-421: Is that it is centralized and easy to remove. A single-file virtual file system may include all the basic features expected of any file system (virtual or otherwise), but access to the internal structure of these file systems is often limited to programs specifically written to make use of the single-file virtual file system (instead of implementation through a driver allowing universal access). Another major drawback

1539-516: Is that performance is relatively low when compared to other virtual file systems. Low performance is mostly due to the cost of shuffling virtual files when data is written or deleted from the virtual file system. Direct examples of single-file virtual file systems include emulators, such as PCTask and WinUAE, which encapsulate not only the filesystem data but also emulated disk layout. This makes it easy to treat an OS installation like any other piece of software—transferring it with removable media or over

1620-411: Is that replacing the implementation of A with another implementation of the same interface should not cause B to fail—how A internally meets the requirements of the interface is not relevant to B , which is only concerned with the specifications of the interface. (See also Liskov substitution principle .) In some object-oriented languages, especially those without full multiple inheritance ,

1701-680: Is to prohibit access to all resources by default, allowing access only through well-defined entry points, i.e., interfaces. Software interfaces provide access to computer resources (such as memory, CPU, storage, etc.) of the underlying computer system; direct access (i.e., not through well-designed interfaces) to such resources by software can have major ramifications—sometimes disastrous ones—for functionality and stability. Interfaces between software components can provide constants , data types , types of procedures , exception specifications, and method signatures . Sometimes, public variables are also defined as part of an interface. The interface of

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1782-640: The Amiga 1000 . They were first offered for sale in August, but by October only 50 had been built, all of which were used by Commodore. Machines only began to arrive in quantity in mid-November, meaning they missed the Christmas buying rush. By the end of the year, they had sold 35,000 machines, and severe cashflow problems made the company pull out of the January 1986 CES. Bad or entirely missing marketing, forcing

1863-542: The Atari Video Computer System 's TIA . When complete, the team began developing a much more sophisticated set of chips, CTIA , ANTIC and POKEY , that formed the basis of the Atari 8-bit computers . With the 8-bit line's launch in 1979, the team once again started looking at a next generation chipset. Nolan Bushnell had sold the company to Warner Communications in 1978, and the new management

1944-406: The C language, and the entire system became AmigaOS. The system was enclosed in a pizza box form factor case; a late change was the introduction of vertical supports on either side of the case to provide a "garage" under the main section of the system where the keyboard could be stored. The first model was announced in 1985 as simply "The Amiga from Commodore", later to be retroactively dubbed

2025-506: The Java language defines the interface Readable that has the single read () method; various implementations are used for different purposes, including BufferedReader , FileReader , InputStreamReader , PipedReader , and StringReader . Marker interfaces like Serializable contain no methods at all and serve to provide run-time information to generic processing using Reflection . The use of interfaces allows for

2106-836: The OpalVision card was popular, although less featured and supported than the Video Toaster. Low-cost time base correctors (TBC) specifically designed to work with the Toaster quickly came to market, most of which were designed as standard Amiga bus cards. Various manufacturers started producing PCI busboards for the A1200, A3000 and A4000, allowing standard Amiga computers to use PCI cards such as graphics cards, Sound Blaster sound cards, 10/100 Ethernet cards, USB cards, and television tuner cards. Other manufacturers produced hybrid boards that contained an Intel x86 series chip, allowing

2187-574: The Sidecar IBM PC compatibility add-on, the Amiga was most commercially successful as a home computer , with a wide range of games and creative software. It also found a niche in video production with the Video Toaster hardware and software, and Amiga's audio hardware made it a popular platform for music tracker software. The processor and memory capacity enabled 3D rendering packages, including LightWave 3D , Imagine , and Traces,

2268-587: The central processing unit (CPU). This architecture gave the Amiga a performance edge over its competitors, particularly for graphics-intensive applications and games. The architecture uses two distinct bus subsystems: the chipset bus and the CPU bus. The chipset bus allows the coprocessors and CPU to address "Chip RAM" . The CPU bus provides addressing to conventional RAM, ROM and the Zorro II or Zorro III expansion subsystems. This enables independent operation of

2349-436: The 2000s. AmigaOS has influenced replacements, clones, and compatible software such as MorphOS and AROS . Currently Belgian company Hyperion Entertainment maintains and develops AmigaOS 4 , which is an official and direct descendant of AmigaOS 3.1 – the last system made by Commodore for the original Amiga computers. Jay Miner joined Atari, Inc. in the 1970s to develop custom integrated circuits , and led development of

2430-566: The 68k CPU and run Linux on the PPC via project Linux APUS, but a PowerPC-native AmigaOS promised by Amiga Technologies GmbH was not available when the PowerUP boards first appeared. 24-bit graphics cards and video cards were also available. Graphics cards were designed primarily for 2D artwork production, workstation use, and later, gaming. Video cards are designed for inputting and outputting video signals, and processing and manipulating video. In

2511-520: The A600 and A1200. They revert the system to temporarily boot in Kickstart v1.3. The keyboard on Amiga computers is similar to that found on a mid-80s IBM PC: Ten function keys, a numeric keypad, and four separate directional arrow keys. Caps Lock and Control share space to the left of A. Absent are Home, End, Page Up, and Page Down keys: These functions are accomplished on Amigas by pressing shift and

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2592-486: The AGA chipset (A1200 and A4000) also have non-EHB 64, 128, 256, and 262144 ( HAM8 Mode ) color modes and a palette expanded from 4096 to 16.8 million colors . The Amiga chipset can genlock , which is the ability to adjust its own screen refresh timing to match an incoming NTSC or PAL video signal. When combined with setting transparency, this allows an Amiga to overlay an external video source with graphics. This ability made

2673-623: The Amiga 1000, v1.2 and v1.3 for the A500, Kickstart v2.1 on A500+, Kickstart v2.2 for A600 and dual ROMs for Kickstart v3.0 and 3.1 for A1200 and A4000. After Commodore's demise there have been new Kickstart v3.1 ROMs made available for both the A500 and A600 Computers. Amiga Software is mostly backward compatible, but v2.1 ROMs and newer differ slightly, which can cause software glitches with earlier programs. To help address this and to get earlier programs to work with later Kickstart ROMs, some tools have been produced such as RELOKIK 1.4 and MAKE IT WORK! for

2754-468: The Amiga brand to Amiga, Inc. , without having released any products. Amiga, Inc. licensed the rights to sell hardware using the AmigaOne brand to Eyetech Group and Hyperion Entertainment . In 2019, Amiga, Inc. sold its intellectual property to Amiga Corporation. The Amiga has a custom chipset consisting of several coprocessors which handle audio, video, and direct memory access independently of

2835-475: The Amiga differs from its contemporaries through the inclusion of custom hardware to accelerate graphics and sound, including sprites and a blitter , and a pre-emptive multitasking operating system called AmigaOS . The Amiga 1000 was released in July 1985, but production problems kept it from becoming widely available until early 1986. The best-selling model, the Amiga 500 , was introduced in 1987 along with

2916-506: The Amiga packaged as a game console, the Amiga CD32 , failed in the marketplace. Escom of Germany, who acquired Commodore properties, continued developing the Amiga line for just under two more years until it also went bankrupt. Since the demise of Commodore and Escom, various groups have marketed successors to the original Amiga line, including Eyetech , ACube Systems Srl and A-EON Technology who have produced AmigaOne computers since

2997-406: The Amiga popular for many applications, and provides the ability to do character generation and CGI effects far more cheaply than earlier systems. This ability has been frequently utilized by wedding videographers, TV stations and their weather forecasting divisions (for weather graphics and radar), advertising channels, music video production, and desktop videographers. The NewTek Video Toaster

3078-494: The Amiga to control up to eight million digitally controlled external audio, lighting, automation, relay and voltage control channels spread around a large theme park, for example. See Amiga software for more information on these applications. Other devices included the following: The Commodore A2232 board provides seven RS-232C serial ports in addition to the Amiga's built-in serial port. Each port can be driven independently at speeds of 50 to 19,200 bits/s . There is, however,

3159-451: The Amiga to emulate a PC. PowerPC upgrades with Wide SCSI controllers, PCI busboards with Ethernet, sound and 3D graphics cards, and tower cases allowed the A1200 and A4000 to survive well into the late nineties. Expansion boards were made by Richmond Sound Design that allow their show control and sound design software to communicate with their custom hardware frames either by ribbon cable or fiber optic cable for long distances, allowing

3240-431: The Commodore 64 in the low-end market. These new designs were released in 1987 as the Amiga 2000 and Amiga 500 , the latter of which went on to widespread success and became their best selling model. Similar high-end/low-end models would make up the Amiga line for the rest of its history; follow-on designs included the Amiga 3000 / Amiga 500 Plus / Amiga 600 , and the Amiga 4000 / Amiga 1200 . These models incorporated

3321-1067: The File System Switch in System V Release 3 , the Generic File System in Ultrix , and the VFS in Linux . In OS/2 and Microsoft Windows , the virtual file system mechanism is called the Installable File System . The Filesystem in Userspace (FUSE) mechanism allows userland code to plug into the virtual file system mechanism in Linux, NetBSD , FreeBSD , OpenSolaris , and macOS. In Microsoft Windows, virtual filesystems can also be implemented through userland Shell namespace extensions ; however, they do not support

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3402-595: The NFS code from Sun often copied the design of Sun's VFS. Other file systems could be plugged into it also: there was an implementation of the MS-DOS FAT file system developed at Sun that plugged into the SunOS VFS, although it wasn't shipped as a product until SunOS 4.1. The SunOS implementation was the basis of the VFS mechanism in System V Release 4 . John Heidemann developed a stacking VFS under SunOS 4.0 for

3483-672: The North American market, the NewTek Video Toaster was a video effects board that turned the Amiga into an affordable video processing computer that found its way into many professional video environments. One well-known use was to create the special effects in early series of Babylon 5 . Due to its NTSC -only design, it did not find a market in countries that used the PAL standard, such as in Europe. In those countries,

3564-518: The application. The absence of Num lock frees space for more mathematical symbols around the numeric pad. Like IBM-compatible computers, the mouse has two buttons, but in AmigaOS, pressing and holding the right button replaces the system status line at the top of the screen with a Maclike menu bar . As with Apple's Mac OS prior to Mac OS 8 , menu options are selected by releasing the button over that option, not by left clicking. Menu items that have

3645-550: The appropriate arrow key. The Amiga keyboard adds a Help key, which a function key usually acts as on PCs (usually F1). In addition to the Control and Alt modifier keys, the Amiga has 2 "Amiga" keys, rendered as "Open Amiga" and "Closed Amiga" similar to the Open/Closed Apple logo keys on Apple II keyboards. The left is used to manipulate the operating system (moving screens and the like) and the right delivers commands to

3726-706: The chip can address only 16 MB of physical memory and is implemented using a 16-bit arithmetic logic unit and has a 16-bit external data bus , so 32-bit computations are transparently handled as multiple 16-bit values at a performance cost. The later Amiga 2500 and the Amiga 3000 models use fully 32-bit, 68000-compatible processors from Motorola with improved performance and larger addressing capability. CPU upgrades were offered by both Commodore and third-party manufacturers. Most Amiga models can be upgraded either by direct CPU replacement or through expansion boards. Such boards often included faster and higher capacity memory interfaces and hard disk controllers. Towards

3807-489: The code with the specific implementations of the interface that will be used to perform the work. A user interface is a point of interaction between a computer and humans; it includes any number of modalities of interaction (such as graphics, sound, position, movement, etc.) where data is transferred between the user and the computer system. Amiga Amiga is a family of personal computers produced by Commodore from 1985 until 1994, with production by others for

3888-473: The company's operations. Among these was the long-overdue cancellation of the now outdated PET and VIC-20 lines, as well as a variety of poorly selling Commodore 64 offshoots and the Commodore 900 workstation effort. Another one of the changes was to split the Amiga into two products, a new high-end version of the Amiga aimed at the creative market, and a cost-reduced version that would take over for

3969-507: The data simultaneously or serial where data are sent one bit at a time. A software interface may refer to a wide range of different types of interfaces at different "levels". For example, an operating system may interface with pieces of hardware. Applications or programs running on the operating system may need to interact via data streams , filters, and pipelines. In object oriented programs , objects within an application may need to interact via methods . A key principle of design

4050-500: The development team to move to the east coast, notorious stability problems and other blunders limited sales in early 1986 to between 10,000 and 15,000 units a month. 120,000 units were reported as having been sold from the machine's launch up to the end of 1986. In late 1985, Thomas Rattigan was promoted to COO of Commodore, and then to CEO in February 1986. He immediately implemented an ambitious plan that covered almost all of

4131-415: The early 1990s. Commodore UK's Kelly Sumner did not see Sega or Nintendo as competitors, but instead credited their marketing campaigns which spent over £40 million or $ 60,000,000 (equivalent to $ 130,000,000 in 2023) for promoting video games as a whole and thus helping to boost Amiga sales. In spite of his successes in making the company profitable and bringing the Amiga line to market, Rattigan

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4212-465: The end of Commodore's time in charge of Amiga development, there were suggestions that Commodore intended to move away from the 68000 series to higher performance RISC processors, such as the PA-RISC . Those ideas were never developed before Commodore filed for bankruptcy. Despite this, third-party manufacturers designed upgrades featuring a combination of 68000 series and PowerPC processors along with

4293-502: The experimental Ficus file system . This design provided for code reuse among file system types with differing but similar semantics ( e.g. , an encrypting file system could reuse all of the naming and storage-management code of a non-encrypting file system). Heidemann adapted this work for use in 4.4BSD as a part of his thesis research; descendants of this code underpin the file system implementations in modern BSD derivatives including macOS . Other Unix virtual file systems include

4374-507: The full 32-bit CPUs of the 68000 family such as the Motorola 68020 and Motorola 68030 , almost always with 32-bit memory and usually with FPUs and MMUs or the facility to add them. Later designs feature the Motorola 68040 or Motorola 68060 . Both CPUs feature integrated FPUs and MMUs. Many CPU accelerator cards also had integrated SCSI controllers. Phase5 designed the PowerUP boards ( Blizzard PPC and CyberStorm PPC ) featuring both

4455-421: The future direction of the company. A number of Commodore employees followed him to his new company, Tramel Technology. This included a number of the senior technical staff, where they began development of a 68000-based machine of their own. In June, Tramiel arranged a no-cash deal to take over Atari, reforming Tramel Technology as Atari Corporation . As many Commodore technical staff had moved to Atari, Commodore

4536-441: The joystick ports; some games, such as Lemmings , were designed to take advantage of this. The Amiga was one of the first computers for which inexpensive sound sampling and video digitization accessories were available. As a result of this and the Amiga's audio and video capabilities, the Amiga became a popular system for editing and producing both music and video. Many expansion boards were produced for Amiga computers to improve

4617-463: The loan to be repaid at the end of the month, otherwise Amiga would forfeit the Lorraine design to Atari. During 1983, Atari lost over $ 1 million a week , due to the combined effects of the crash and the ongoing price war in the home computer market. By the end of the year, Warner was desperate to sell the company. In January 1984, Jack Tramiel resigned from Commodore due to internal battles over

4698-519: The lowest-level file system access application programming interfaces in Windows, so not all applications will be able to access file systems that are implemented as namespace extensions. KIO and GVfs / GIO provide similar mechanisms in the KDE and GNOME desktop environments (respectively), with similar limitations, although they can be made to use FUSE techniques and therefore integrate smoothly into

4779-527: The more expandable Amiga 2000 . The Amiga 3000 was introduced in 1990, followed by the Amiga 500 Plus , and Amiga 600 in March 1992, followed by the Amiga 1200 and Amiga 4000 . Estimates of Amiga sales figures vary, with several older sources presenting values between 4.85 (purely Commodore Amiga sales) and 5.29 million (including Escom sales). While early advertisements cast the computer as an all-purpose business machine, especially when outfitted with

4860-613: The network. The Amiga emulator PCTask emulated an Intel PC 8088 based machine clocked at 4.77 MHz (and later an 80486 SX clocked at 25 MHz). Users of PCTask could create a file of large size on the Amiga filesystem, and this file would be virtually accessed from the emulator as if it were a real PC Hard Disk. The file could be formatted with the FAT16 filesystem to store normal MS-DOS or Windows files. The UAE for Windows , WinUAE , allows for large single files on Windows to be treated as Amiga file systems. In WinUAE this file

4941-463: The official logo of Escom subsidiary Amiga Technologies. CES attendees had trouble believing the computer being demonstrated had the power to display such a demo and searched in vain for the "real" computer behind it. A further developed version of the system was demonstrated at the June 1984 CES and shown to many companies in hopes of garnering further funding, but found little interest in a market that

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5022-552: The partly 32-bit Advanced Graphics Architecture (AGA) in 1992. Each chipset consists of several coprocessors that handle graphics acceleration , digital audio, direct memory access and communication between various peripherals (e.g., CPU, memory and floppy disks). In addition, some models featured auxiliary custom chips that performed tasks such as SCSI control and display de-interlacing. All Amiga systems can display full-screen animated planar graphics with 2, 4, 8, 16, 32, 64 ( EHB Mode ), or 4096 colors ( HAM Mode ). Models with

5103-525: The performance and capability of the hardware, such as memory expansions, SCSI controllers, CPU boards, and graphics boards. Other upgrades include genlocks , network cards for Ethernet , modems , sound cards and samplers, video digitizers , extra serial ports , and IDE controllers. Additions after the demise of Commodore company are USB cards. The most popular upgrades were memory, SCSI controllers and CPU accelerator cards. These were sometimes combined into one device. Early CPU accelerator cards used

5184-509: The power LED had no relation to the filter's status, and a wire needed to be manually soldered between pins on the sound chip to disable the filter. Paula can read arbitrary waveforms at arbitrary rates and amplitudes directly from the system's RAM , using direct memory access (DMA), making sound playback without CPU intervention possible. Although the hardware is limited to four separate sound channels, software such as OctaMED uses software mixing to allow eight or more virtual channels, and it

5265-457: The protocol for sequencing them (sometimes called signaling). A standard interface, such as SCSI , decouples the design and introduction of computing hardware, such as I/O devices, from the design and introduction of other components of a computing system, thereby allowing users and manufacturers great flexibility in the implementation of computing systems. Hardware interfaces can be parallel with several electrical connections carrying parts of

5346-401: The same time. An interface is thus a type definition; anywhere an object can be exchanged (for example, in a function or method call) the type of the object to be exchanged can be defined in terms of one of its implemented interface s or base-classes rather than specifying the specific class . This approach means that any class that implements that interface can be used. For example,

5427-522: The subsidiary company Amiga Technologies. They re-released the A1200 and A4000T, and introduced a new 68060 version of the A4000T. Amiga Technologies researched and developed the Amiga Walker prototype. They presented the machine publicly at CeBit, but Escom went bankrupt in 1996. Some Amigas were still made afterwards for the North American market by QuikPak, a small Pennsylvania -based firm who

5508-437: The subsystems. The CPU bus can be much faster than the chipset bus. CPU expansion boards may provide additional custom buses. Additionally, "busboards" or "bridgeboards" may provide ISA or PCI buses. The most popular models from Commodore, including the Amiga 1000 , Amiga 500 , and Amiga 2000 , use the Motorola 68000 as the CPU. From a developer's point of view, the 68000 provides a full suite of 32-bit operations, but

5589-599: The system hardware was being readied for production. At this time the operating system (OS) was not as ready, and led to a deal to port an OS known as TRIPOS to the platform. TRIPOS was a multitasking system that had been written in BCPL during the 1970s for the PDP-11 minicomputer , but later experimentally ported to the 68000. This early version was known as AmigaDOS and the GUI as Workbench. The BCPL parts were later rewritten in

5670-506: The system. Sometimes Virtual File System refers to a file or a group of files (not necessarily inside a concrete file system) that acts as a manageable container which should provide the functionality of a concrete file system through the usage of software. Examples of such containers are CBFS Storage or a single-file virtual file system in an emulator like PCTask or so-called WinUAE , Oracle's VirtualBox , Microsoft's Virtual PC , VMware . The primary benefit for this type of file system

5751-440: The term interface is used to define an abstract type that acts as an abstraction of a class . It contains no data, but defines behaviours as method signatures. A class having code and data for all the methods corresponding to that interface and declaring so is said to implement that interface. Furthermore, even in single-inheritance-languages, one can implement multiple interfaces, and hence can be of different types at

5832-438: Was designed by Miner, RJ Mical , and Dale Luck. A breadboard prototype for testing and development was largely completed by late 1983, and shown at the January 1984 Consumer Electronics Show (CES). At the time, the operating system was not ready, so the machine was demonstrated with the "Boing Ball" demo, a real-time animation showing a red-and-white spinning ball bouncing and casting a shadow; this bouncing ball later became

5913-548: Was developed allowing these cards to be used transparently by the OS and software. Kickstart is the firmware upon which AmigaOS is bootstrapped . Its purpose is to initialize the Amiga hardware and core components of AmigaOS and then attempt to boot from a bootable volume , such as a floppy disk or hard disk drive. Most models (excluding the Amiga 1000) come equipped with Kickstart on an embedded ROM-chip . There are various editions of Kickstart ROMs starting with Kickstart v1.1 for

5994-406: Was in the final stages of the video game crash of 1983 . In March, Atari expressed a tepid interest in Lorraine for its potential use in a games console or home computer tentatively known as the 1850XLD . The talks were progressing slowly, and Amiga was running out of money. A temporary arrangement in June led to a $ 500,000 loan from Atari to Amiga to keep the company going. The terms required

6075-532: Was left with no workable path to design their own next-generation computer. The company approached Amiga offering to fund development as a home computer system. They quickly arranged to repay the Atari loan, ending that threat. The two companies were initially arranging a $ 4 million license agreement before Commodore offered $ 24 million to purchase Amiga outright. By late 1984, the prototype breadboard chipset had successfully been turned into integrated circuits, and

6156-625: Was less popular in North America, where an estimated 700,000 were sold. In the United States, the Amiga found a niche with enthusiasts and in vertical markets for video processing and editing. In Europe, it was more broadly popular as a home computer and often used for video games . Beginning in 1988 it overlapped with the 16-bit Mega Drive , then the Super Nintendo Entertainment System in

6237-488: Was made possible by the genlock ability of the Amiga. In 1988, the release of the Amiga A2024 fixed-frequency monochrome monitor with built-in framebuffer and flicker fixer hardware provided the Amiga with a choice of high-resolution graphic modes (1024×800 for NTSC and 1024×1024 for PAL). ReTargetable Graphics is an API for device drivers mainly used by 3rd party graphics hardware to interface with AmigaOS via

6318-434: Was much more interested in the existing lines than development of new products that might cut into their sales. Miner wanted to start work with the new Motorola 68000 , but management was only interested in another 6502 based system. Miner left the company, and, for a time, the industry. In 1979, Larry Kaplan left Atari and founded Activision . In 1982, Kaplan was approached by a number of investors who wanted to develop

6399-683: Was possible for software to mix two hardware channels to achieve a single 14-bit resolution channel by playing with the volumes of the channels in such a way that one of the source channels contributes the most significant bits and the other the least. The quality of the Amiga's sound output, and the fact that sound hardware is part of the standard chipset and easily addressed by software, were standout features of Amiga hardware unavailable on PC platforms for years . Third-party sound cards exist that provide DSP functions , multi-track direct-to-disk recording , multiple hardware sound channels and 16-bit and beyond resolutions. A retargetable sound API called AHI

6480-407: Was soon forced out in a power struggle with majority shareholder, Irving Gould . This is widely regarded as the turning point, as further improvements to the Amiga were eroded by rapid improvements in other platforms. Commodore shut down the Amiga division on April 26, 1994, and filed for bankruptcy three days later. Commodore's assets were purchased by Escom , a German PC manufacturer, who created

6561-480: Was the manufacturer of Amigas for Escom. After a reported sale to VisCorp fell through, a U.S. Wintel PC manufacturer, Gateway 2000 , eventually purchased the Amiga branch and technology in 1997. QuickPak attempted but failed to license Amiga from Gateway and build new models. Gateway was then working on a brand new Amiga platform, likely encouraged by a desire to be independent of Microsoft and Intel . However this did not materialize and in 2000, Gateway sold

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