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Alpha Micro
- History

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Alpha Microsystems was founded in 1977 by John French, Dick Wilcox and Bob Hitchcock. The first Alpha Micro computer was the S-100 based AM-100. It was a two board set. The CPU was the WD16 microprocessor chipset (5) from Western Digital.  The WD16 was a  16 bit CPU, completely symmetric source and destination addressing modes. There were eight main addressing modes and a number of variations. It had block move, block I/O, and multi-bit shifts and rotates. It even had five 48-bit floating point instructions, ADD, SUB, MUL, DIV, and CMP. All running at 2MHz.   Eventually the speed went up to 3.3 MHZ.

Later computers starting with the AM-100/L and the AM-1000 were based on the Motorola 68000 and succeeding processors, though Alpha Micro swapped several addressing lines to create byte-ordering compatibility with their earlier processor. The company's primary claim to fame was selling  minicomputers that provided multi-user power using their proprietary operating system called AMOS (Alpha Micro Operating System).  AMOS had major similarities to the operating system of the DEC PDP-11. This may not be coincidental; legend has it that the founders based their operating system on "borrowed" source code from DEC, and DEC, perceiving the same, unsuccessfully tried to sue Alpha Micro over the similarities in 1984.  

As Motorola stopped developing their 68000 product, Alpha Micro started to move to the x86 CPU family. This was initially done with their "Falcon" cards, allowing standard DOS and later Windows-based PCs to run AMOS applications on the 68000-series CPU using the Falcon card. Later AMOS version 8, ran natively on x86 CPU's, but includes a 68K emulator to run older software. For application development, AMOS used their own BASIC-like language called Alpha BASIC. Early Alpha Micro System using the AM-100 CPU could have up to nine users and two spooled printers attached to it. It supported all of them typically in 300K or more of RAM. It had an 8" 40 megabyte Quantum hard drive. This drive had four platters and eight heads.  The system also typically had a Control Data Hawk 5 meg fixed and a 5 meg removable drive and two 8" single sided floppies with 250K each for data backup.

In the past, Alpha Micro bundled their operating system and tools such as BASIC as part of the hardware sale. Gradually, Alpha Micro transitioned to charging for their software as hardware became more of a commodity item. The Alpha Micro computer never achieved mainstream name recognition, though it had been traditionally popular in certain vertical markets, particularly medical and dental offices.

Alpha Micro went through a confusing series of name swaps and changes of ownership in the late 1990s and early 2000s, although all of them were still informally called Alpha Micro. In 1999 they were called AlphaServ.com, in 2000 they were AlphaCONNECT.  In 2001, the product division was split off and acquired by AMOS vendor Birmingham Data Systems' Alpha Micro Products branch (AMP), while AMSO was sold to the service firm Optimal Robotics. In 2003 AMP bought back the Alpha Microsystems and AMSO trademarks where they currently remain.

Alpha Micro was never in the realm of computer hobbyists, their systems were simply too expensive. That said they were the first S-100 board company to utilize the S-100 bus for a 16 bit CPU.  However it should be remembered that Alpha Micro utilized some of the unused original S-100 bus lines for their own purposes. For example they had 7 DMA request lines ((pins 63-56). Thus their boards would not work in a IEEE-696 system. Indeed they may not work with many older non-Alpha Micro S-100 boards.

For more infornation on Alpha Micro Systems see here.


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This page was last modified on 06/26/2015