Amiga 1000

Commodore Amiga 1000

Type	Personal computer
Release date	24 July 1985
Discontinued	1987
Operating system	Amiga OS 1.0
CPU	Motorola 68000 @ 7.16 MHz (NTSC) 7.09 MHz (PAL)
Memory	256 – 512 KB (8 MB Maximum)
Graphics	OCS 640×256 5-bpp
Sound	Paula 4x 8-bit channels at max 28 kHz with 6-bit volume in stereo.
Predecessor	Commodore 128
Successor	Amiga 500, Amiga 2000

The A1000, or Commodore Amiga 1000, was Commodore's initial Amiga personal computer, introduced on July 24, 1985 at the Lincoln Center in New York City. Machines began shipping in September with a base configuration of 256 KB of RAM at the retail price of 1295 USD. A 13-inch (330 mm) analog RGB monitor was available for around 300 USD bringing the price of a complete Amiga system to 1595 USD. Before the release of the Amiga 500 and A2000 models in 1987, the A1000 was simply called Amiga.

In the US, the A1000 was marketed as The Amiga from Commodore, however the Commodore logo was omitted from the casing. Additionally the Amiga 1000 was exclusively sold in computer stores, rather than the various non-computer related stores the Commodore 64 were retailed in. These measures were an effort to avoid Commodore's "toy-store" computer image created during the Tramiel era.

Design

The A1000 had a number of characteristics that distinguished it from later Amigas: It was the only model to feature the short-lived Amiga "checkmark" logo on its case; the case was elevated slightly to give a storage area for the keyboard when not in use (a "keyboard garage"); and the inside of the case was engraved with the signatures of the Amiga designers, including Jay Miner, and the paw print of his dog Mitchy. The A1000's case was designed by Howard Stolz As Senior Industrial Designer at Commodore, Stolz was the mechanical lead and primary interface with Sanyo in Japan, the contract manufacturer for the A1000 casing.

Because AmigaOS was rather buggy at the time of the A1000's release, the OS was not placed in ROM. Instead, the A1000 included a daughterboard with 256 KB of RAM, dubbed the "Writable Control Store" (WCS), into which the core of the operating system was loaded from floppy disk (this portion of the operating system was known as the "Kickstart"). The WCS was write-protected after loading, and system resets did not require a reload of the WCS. In Europe the WCS was often referred to as WOM (Write Once Memory) rather than the more conventional ROM (Read Only Memory).

Many A1000 owners remained attached to their machines long after newer models rendered the units technically obsolete, and it attracted numerous aftermarket upgrades. Many CPU upgrades that plugged into the Motorola 68000 socket functioned in the A1000. Additionally, a line of products called the Rejuvenator series allowed the use of newer chipsets in the A1000, and an Australian-designed replacement A1000 motherboard called The Phoenix utilized the same chipset as the A3000 and added an A2000-compatible video slot and onboard SCSI controller.

In 2006 PC World rated the Amiga 1000 as the 7th greatest PC of all time [1]. In 2007 it was rated by the same magazine as the 37th best tech product of all time [2]. In 1994, as Commodore filed for bankruptcy, Byte magazine called the Amiga 1000 "the first multimedia computer... so far ahead of its time that almost nobody--including Commodore's marketing department--could fully articulate what it was all about."[3]

Technical information

The Amiga 1000 had a 7.15909 MHz 68000 CPU (7.09 MHz for PAL machines). This is precisely double the 3.58 MHz NTSC color carrier frequency, and was needed by the Amiga chipset when outputting NTSC video. All frequencies in the Amiga 1000 are derived from this frequency as it simplified glue logic and allowed the Amiga 1000 to make do with a single cheap mass-produced crystal. The chipset was also designed to synchronize all operations so the hardware always ran in 100% real-time without any wait-state delays.

Though most units were sold with an analog RGB monitor, the A1000 also had a built-in composite video output which allowed the computer to be connected directly to a TV or VCR.

A direct replacement of the standard 7 MHz 68000 CPU with a 68010 CPU is possible, with the 68010 executes instructions slightly faster than the 68000, however the conversion also introduces a small degree of software incompatibility. An Expansion card, plugging into the CPU socket, became available that has both the original 68000 and a faster 14 MHz 68020/68881 and built-in memory that's mostly compatible and can be switched back to the 68000 for 100% compatibility. A similar 33 MHz 68030/68882 accelerator board was also available. For the 68020 boards most had a socket for the removed 68000 to be plugged into, the 68030 cards usually had a 68000 already on board. Expansion box options were also available including a Zorro-I bus expander which gave you two Zorro-II slots.

Technical specifications

Jay Miner's signature from the top cover of a Commodore Amiga 1000 computer. The paw print is that of Mitchy, Miner's dog.

Rear view of the A1000.

• CPU: Motorola 68000 (7.16 MHz NTSC, 7.09 MHz PAL)
• Chipset: OCS (Original Chipset)
  • Audio (Paula):
    • 4 voices / 2 channels (Stereo)
    • 8-bit resolution / 6-bit volume
    • 28 kHz sampling rate
    • 70 dB S/N Ratio
  • Video (Common NTSC resolutions):
    • 320×200 with 32 colors or HAM-6 (4096 colors)
    • 320×400i with 32 colors or HAM-6 (4096 colors)
    • 640×200 with 16 colors
    • 640×400i with 16 colors
• Memory:
  • 8 KB ROM for bootstrap code.
  • 256 KB WOM for the OS loaded from kickstart.
  • 256 KB of Chip RAM by default, with an additional 256 KB provided by a dedicated cartridge.
  • Practical upper limit of about 9 MB of Fast RAM memory due to being limited to an 24-bit address bus.
    • This memory can not be utilized by the chipset, and is therefore faster.
• Removable Storage:
  • 3.5" DD Floppy drive, capacity 880 KB
• Input/Output connections:
  • Composite TV out (PAL versions sold in Europe and Australia, NTSC elsewhere)
  • Analogue RGB video plug
  • RCA audio plugs, 300 Ohm impedance.
  • 2 × Game/Joy ports (used by the mouse)
  • Keyboard port
  • RS232 Serial port (DB25)
  • Centronics Parallel port (DB25)
  • Port for external floppy drive
  • One expansion port for add-ons (memory, SCSI adaptor, etc), electrically and physically identical to the Amiga 500 expansion port (though the Amiga 500's version is inverted)
    • Resources handled by AutoConfig.
• Software (Bundled):
  • AmigaOS 1.0/1.1/1.2/1.3 operating system, loaded from the Kickstart floppy disk at power-on.
  • Microsoft AmigaBASIC
  • Voice synthesis library

The two versions of the A1000

There were two versions of the Amiga 1000. The first one was sold only in Canada and the United States, had a NTSC display and lacked the EHB video mode which all other models of the Amiga had. Later units of this version would had the EHB mode built in. The second one had a PAL display and the EHB video mode, and was built in Germany.

See also

• Amiga models and variants

External links

• The Commodore Amiga A1000 at OLD-COMPUTERS.COM
• Famous Amiga Uses