 | |
 A500 with 1084S monitor and Amiga 1010 external second floppy drive | |
| Developer | Commodore International |
|---|---|
| Product family | Amiga |
| Type | Home computer |
| Release date | April 1987 (Netherlands) May 1987 (Europe) October 1987 (US/UK) |
| Introductory price |
|
| Discontinued | 1992 (1992) |
| Units sold | 2.6 million[1] 1,160,500 units in Germany (including Amiga 500 Plus sales) |
| Media | 880 KB floppy disks |
| Operating system | AmigaOS v1.2 – 1.3 (upgradable to current version if enough RAM is installed) |
| CPU | Motorola 68000 @7.16 MHz (NTSC) 7.09 MHz (PAL) |
| Memory | 512 or 1024 KB 150 ns (maximum 9 to 138 MB, depending on upgrades)[a][b] |
| Display | 736×567i 4 bpp (PAL) 736×483i 4 bpp (NTSC) 368×567i 6 bpp (PAL) 368×483i 6 bpp (NTSC) |
| Graphics | Denise |
| Sound | 4× 8-bit channelsPCM at max.28kHz with 6-bit volume in stereo |
| Predecessor | Amiga 1000 |
| Successor | |
TheAmiga 500, also known as theA500, was the first popular version of theAmiga home computer. It contains the sameMotorola 68000 as theAmiga 1000, as well as the same graphics and sound coprocessors, but is in a smaller case similar to that of theCommodore 128. Released in 1987, the Amiga 500 was the first computer for the home market capable ofmultitasking. As well, it featured rich color graphics at a time when most high-end computer systems like thePersonal Computer and theoriginal Macintosh either had limited color or were entirely monochrome.[2]
Commodore announced the Amiga 500 at the January 1987 winterConsumer Electronics Show – at the same time as the high-endAmiga 2000. It was initially available in the Netherlands in April 1987, then the rest of Europe in May.[3] In North America and the UK it was released in October 1987 with aUS$699/£499 list price. It competed directly against models in theAtari ST line.
The Amiga 500 was sold in the same retail outlets as theCommodore 64, as opposed to the computer store-only Amiga 1000. It proved to be Commodore's best-selling model, particularly in Europe.[4] Although popular with hobbyists, arguably its most widespread use was as a gaming machine, where its graphics and sound were of significant benefit. It was followed by a revised version of the computer, theAmiga 500 Plus, and the 500 series was discontinued in 1992.
In mid-1988, the Amiga 500 dropped its price from£499 to £399,[5] and it was later bundled with theBatman Pack in the United Kingdom (from October 1989 to September 1990) which included the gamesBatman,F/A-18 Interceptor,The New Zealand Story and the bitmap graphics editorDeluxe Paint 2.[6] Also included was theAmiga video connector which allows the A500 to be used with a conventional CRT television.
In November 1991, the enhancedAmiga 500 Plus replaced the 500 in some markets. It was bundled with theCartoon Classics pack in the United Kingdom at £399, although many stores still advertised it as an 'A500'.[7] The Amiga 500 Plus was virtually identical except for its new operating system, integrated 1MB of Chip memory, different 'trap-door' expansion slot and slightly different keyboard, and in mid-1992, the two were discontinued and effectively replaced by theAmiga 600.[8] In late 1992, Commodore released theAmiga 1200, a machine closer in concept to the original Amiga 500, but with significant technical improvements. Despite this, neither the A1200 nor the A600 replicated the commercial success of its predecessor. By this time, the home market was strongly shifting toIBM PC compatibles withVGA graphics and the low-costMacintosh Classic,LC, andIIsi models.[9]
Outwardly resembling theCommodore 128[10] and codenamed "Rock Lobster" during development,[11] the Amiga 500's base houses a keyboard and a CPU in one shell, unlike theAmiga 1000. The keyboard for Amiga 500s sold in the United States contains 94 keys, including tenfunction keys, four cursor keys, and a number pad. All European versions the keyboard have an additional two keys, except for the British variety, which still uses 94 keys.[12] It uses a Motorola 68000 microprocessor running at7.15909 MHz inNTSC regions and7.09379 MHz inPAL regions.[13] The CPU implements a 32-bit model and has 32-bit registers, but it has a 16-bit mainALU and uses a 16-bit external data bus and a 24-bit address bus, providing a maximum of 16 MB ofaddress space.[a][14][15] Also built in to the base of the computer is a3+1⁄2-inch floppy disk drive. The user can also install up to three external floppy drives, either3+1⁄2- or5+1⁄4-inch, via the disk drive port. The second and third additional drives are installed bydaisy-chaining them. Supported by these drives are double-sided disks with a capacity of 901,120 bytes, as well as 360- and 720-KB disks formatted for IBM PC compatibles.[16]
The earliest Amiga 500 models use nearly the sameOriginal Amiga chipset as the Amiga 1000.[c] So graphics can be displayed in multiple resolutions and color depths, even on the same screen. Resolutions vary from 320×200 (up to 32 colors) to 640×400 (up to 16 colors) for NTSC (704×484 overscan) and 320×256 to 640×512 for PAL (704×576 overscan.)[17] The system usesplanar graphics, with up to five bitplanes (four in high resolution) allowing 2-, 4-, 8-, 16-, and 32-color screens, from a palette of 4096 colors. Two special graphics modes are also available: Extra HalfBrite, which uses a sixth bitplane as a mask to cut the brightness of any pixel in half (resulting in 32 arbitrary colors plus 32 more colors set at half the value of the first 32), andHold-And-Modify (HAM) which allows all 4096 colors to be used on screen simultaneously.[18] Later revisions of the chipset arePAL/NTSC switchable in software.
The sound chip produces four hardware-mixed channels, two to the left and two to the right, of 8-bit PCM at a sampling frequency up to28 kHz. Each hardware channel has its own independent volume level and sampling rate, and can be designated to another channel where it can modulate both volume and frequency using its own output. WithDMA disabled it's possible to output with a sampling frequency up to56 kHz. There is a common trick tooutput sound with 14-bit precision that can be combined to output 14-bit56 kHz sound.[19]
The stock system comes withAmigaOS version 1.2 or 1.3 and512 KB[a] ofchip RAM (150 ns access time), one built-in double-densitystandard floppy disk drive that is completely programmable and can read720 KBIBM PC disks,880 KB standard Amiga disks, and up to984 KB using custom-formatting drivers.
Despite the lack ofAmiga 2000-compatible internal expansion slots, there are many ports and expansion options. There are twoDE9MAtari joystick ports forjoysticks ormice, and stereo audioRCA connectors (1 Vp-p). There is a floppy drive port for daisy-chaining up to three extra floppy disk drives via a DB23F connector.[20] The then-standardRS-232 serial port (DB25M) andCentronicsparallel port (DB25F) are also included. The power supply is (+5 V,±12 V).[21] The system displays video in analogRGB50 Hz PAL or60 Hz NTSC through a proprietary DB23M connector and in NTSC mode the line frequency is15.75 kHzHSync for standard video modes, which is compatible with NTSC television and CVBS/RGB video, but out of range for mostVGA-compatible monitors, while amultisync monitor is required for some of the higher resolutions. This connection can also begenlocked to an external video signal. The system was bundled with anRF adapter to provide output on televisions with a coaxial RF input, while monochrome video is available via anRCA connector (also coaxial). On the left side, behind a plastic cover, there is a Zorro (Zorro I) bus expansion external edge connector with 86 pins. Peripherals such as a hard disk drive can be added via the expansion slot and are configured automatically by the Amiga'sAutoConfig standard, so that multiple devices do not conflict with each other. Up to8 MB[a] of so-called "fast RAM" (memory that can be accessed by the CPU only) can be added using the side expansion slot. This connector is electronically identical with the Amiga 1000's, but swapped on the other side.
The Amiga 500 has a "trap-door" slot on the underside for a RAM upgrade (typically512 KB)[a]. This extra RAM is classified as "fast" RAM, but is sometimes referred to as "slow" RAM: due to the design of the expansion bus, it is actually on the chipset bus. Such upgrades usually include a battery-backedreal-time clock. All versions of the A500 can have the additional RAM configured as chip RAM by a simple hardware modification, which involves fitting a later model (8372A)Agnus chip. Likewise, all versions of the A500 can be upgraded to2 MB[a] chip RAM by fitting the8372B Agnus chip and adding additional memory.
The Amiga 500 also sports an unusual feature for a budget machine, socketed chips, which allow easy replacement of defective chips. The CPU can be directly upgraded on the motherboard to a68010; or to a68020,68030, or68040 via the side expansion slot; or by removing the CPU and plugging a CPU expansion card into the CPU socket (this requires opening the computer and thus voided any remaining warranty). In fact, all the custom chips can be upgraded to theAmiga Enhanced Chip Set (ECS) versions.
The plastic case is made ofacrylonitrile butadiene styrene, or ABS. ABS degrades with time due to exposure to oxygen, causing a yellowing of the case. Other factors contributing to the degradation and yellowing include heat, shear, and ultraviolet light. The yellowing can be reversed by using anoptical brightener, though withoutstabilizing agents or antioxidants to block oxygen, the yellowing will return.[22][23]
Using various expansion techniques, the A500's total RAM can reach up to 138 MB – 2 MB Chip RAM, 8 MB 16-bit Fast RAM, and 128 MB 32-bit Fast RAM.[a]
The stock 512 KB Chip RAM can be complemented by 512 KB using a "trapdoor" expansion (Commodore A501 or compatible).[a] While that expansion memory is connected to the chip bus, hardware limitations of early stock Agnus chip revisions prevent its use as Chip RAM, only the CPU can access it. Suffering from the same contention limitations as Chip RAM, that memory is known as "Slow RAM" or "Pseudo-fast RAM". Agnus revisions shipped with late A500 areECS and allow use of trapdoor RAM as real Chip RAM for a total 1 MB.[a]
Additionally, several third-party expansions exist with up to 2 MB[a] on the trapdoor board. Using aGary adapter, that memory will be mapped as either split on Chip RAM and Slow RAM or fully as Slow RAM, depending on configuration.
Furthermore, using anA3000 Agnus on an adapter board, it is possible to expand the Chip RAM to 2 MB, matching the A500+.[a]
"Fast" RAM is located on the CPU-side bus. Its access is exclusive to the CPU and not slowed by any chipset access. The side expansion port allows for up to 8 MB[a] ofZorro-style expansion RAM. Alternatively, a CPU adapter allows for internal expansion.
Internal or external CPU accelerators often include their own expansion memory. 16-bit CPUs are limited by the 24-bit address space but they can repurpose otherwise unused memory space for their included RAM. 32-bit CPU accelerators aren't limited by 24-bit addressing and can include up to 128 MB[a] of Fast RAM (and potentially more).
| Address | Size in KB[a] | Description |
|---|---|---|
| 0x00 0000 | 256 | Chip RAM |
| 0x04 0000 | 256 | Chip RAM (A1000 option card) |
| 0x08 0000 | 512 | Chip RAM expansion |
| 0x10 0000 | 1024 | Extended Chip RAM forECS/AGA |
| 0x20 0000 | 8192 | Primary auto-config space (Fast RAM) |
| 0xA0 0000 | 1984 | Reserved |
| 0xBF D000 | 3.8 | 8520-B (even-byte addresses) |
| 0xBF E001 | 3.8 | 8520-A (odd-byte addresses) |
| 0xC0 0000 | 1536 | Internal expansion memory (pseudo-fast, "slow" RAM on Amiga 500) |
| 0xD8 0000 | 256 | Reserved |
| 0xDC 0000 | 64 | Real time clock |
| 0xDD 0000 | 188 | Reserved |
| 0xDF F000 | 4 | Custom chip registers |
| 0xE0 0000 | 512 | Reserved |
| 0xE8 0000 | 64 | Zorro II auto-config space (before relocation) |
| 0xE9 0000 | 448 | Secondary auto-config space (usually 64K I/O boards) |
| 0xF0 0000 | 512 | 512K System ROM (reserved for extended ROM image e.g. CDTV or CD32) |
| 0xF8 0000 | 256 | 256K System ROM (Kickstart 2.04 or higher) |
| 0xFC 0000 | 256 | 256K System ROM |
When the computer is powered on a self-diagnostic test is run that will indicates failure with a specific colour:
The keyboardLED uses blink codes:
Measurements
Overall (base): 6.2 cm x 47.4 cm x 33 cm; 2 7/16 in x 18 11/16 in x 13 in.[34]
 | This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(June 2023) (Learn how and when to remove this message) |
A popular expansion for the Amiga 500 was the Amiga 501 circuit board that can be installed underneath the computer behind a plastic cover. The expansion contains512 KB RAM configured by default as "Slow RAM" or "trap-door RAM" and a battery-backedreal-time clock (RTC).[35]
The 512 KB trap-door RAM and 512 KB of original chip RAM will result in 1 MB of total memory.[a] The added memory is known as "Slow RAM", as its access is impacted by chip-bus bandwidth contention, while the chipset is not actually able to address it.
Later revisions of the motherboard provide solder-jumpers to relocate the trap-door RAM to the chip memory pool, given theAgnus chip is the newer ECS version, shipped in later A500 motherboards. Newest (rev 8) A500s would share motherboard with A500+, and configure the expansion memory as CHIP by default.
![[icon]](/mt/?noimg=&dark=on&url=https%3a%2f%2fen.wikipedia.org%2fwiki%2fFile%3aWiki_letter_w_cropped.svg) | This sectionneeds expansion. You can help byadding to it.(November 2021) |
Each time the Amiga 500 is booted, it executes code from theKickstart ROM. The Amiga 500 initially came shipped withAmigaOS 1.2, but units since October 1988 had version 1.3 installed.[36][37]
The Amiga 500 was the best-selling model in the Amiga family of computers. The German computer magazineChip awarded the model the annual "Home Computer of the Year" title three consecutive times.[38] At theEuropean Computer Trade Show 1991, it also won the Leisure Award for the similar "Home Computer of the Year" title.[39]
Owing to the inexpensive cost of the Amiga 500 in then price-sensitive Europe, sales of the Amiga family of computers were strongest there, constituting 85 percent of Commodore's total sales in the fourth quarter of 1990. The Amiga 500 was widely perceived as a gaming machine and the Amiga 2000 a computer for artists and hobbyists.[40]
It has been claimed[41][42][43] that Commodore sold as many as six million units worldwide. However, Commodore UK refuted that figure and said that the entire Amiga line sold between four and five million computers.[1] Indeed,Ars Technica provides a year-by-year graph of the sales of all Amiga computers.[44]
The machine is reported to have sold 1,160,500 units in Germany (including Amiga 500 Plus sales).[45]
.jpg) Base of the Amiga 500 Plus, with the Italian variant of the keyboard | |
| Developer | Commodore International |
|---|---|
| Product family | Amiga |
| Type | Home computer |
| Release date | October 1991; 34 years ago (1991-10) (UK) |
| Discontinued | June 1992; 33 years ago (1992-06) |
| Media | 880KB floppy disks |
| Operating system | AmigaOS v2.04 |
| CPU | Motorola 68000 @7.16 MHz (NTSC) 7.09 MHz (PAL) |
| Memory | 1MB (10MB maximum) |
| Display | 640×256, 4bpp @50Hz (PAL) 640×200, 4bpp @60Hz (NTSC) |
| Sound | 4× 8-bit channels PCM at max.28kHz with 6-bit volume in stereo |
| Predecessor | Amiga 500 |
| Successor | Amiga 600 |
TheAmiga 500 Plus (oftenA500 Plus or simplyA500+) is a revised version of the original Amiga 500 computer. The A500+ featured minor changes to the motherboard to make it cheaper to produce than the original A500. It was notable for introducing new versions ofKickstart andWorkbench, and for some minor improvements in the custom chips, known as theEnhanced Chip Set (or ECS).
Although officially introduced in 1992, some Amiga 500 units sold in late 1991 actually featured the revised motherboard used in the A500+. Although the Amiga 500+ was an improvement to the Amiga 500, it was minor. It was discontinued and replaced by theAmiga 600 in summer 1992, making it the shortest-lived Amiga model.[46]
| This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(March 2021) (Learn how and when to remove this message) |
Due to the new Kickstart v2.04, quite a few popular games (such asTreasure Island Dizzy,Lotus Esprit Turbo Challenge, andSWIV) failed to work on the Amiga 500+, and some people took them back to dealers demanding an originalKickstart 1.3 Amiga 500. This problem was largely solved by third parties who produced KickstartROM switching boards, that could allow the Amiga 500+ to be downgraded to Kickstart 1.2 or 1.3. It also encouraged game developers to use better programming habits, which was important since Commodore already had plans for the introduction of the next-generationAmiga 1200 computer. A program, Relokick, was also released (and included with an issue ofCU Amiga) which loaded aKickstart 1.3ROM image into memory and booted the machine into Kickstart 1.3, allowing most incompatible software to run (the software did take up 512 KB of system memory, meaning that some 1 MB only games would now fail for lack of available memory). In some cases, updated compatible versions of games were later released, such as budget versions ofLotus 1 andSWIV, and an update toBubble Bobble.Double Dragon 2 by Binary Design received an update forECS machines with the "Amiga phase-alternated linescan version 4.01/ECS". This solved compatibility issues with the graphics which appeared garbled on ECS machines, and it also slashed the in-game loading times from around 20 seconds to just over 6.
Everything George Robbins worked on was some reference to the B-52's.
{{cite web}}: CS1 maint: bot: original URL status unknown (link)
| People |
|  | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Subsidiaries | |||||||||||
| Computers† |
| ||||||||||
| Other hardware | |||||||||||
| Software | |||||||||||
| See also | |||||||||||
† Listed in chronological order by category | |||||||||||
