The Z-80 SoftCard is a plug-in card supplied by Microsoft for use with the Apple II personal computer. The Apple II does not have a Z80-compatible processor and cannot run CP/M. The SoftCard has a Zilog Z80 CPU plus some 74LS00 series TTL chips to adapt that processor's bus to the Apple bus. The card was eventually renamed the Microsoft SoftCard.
Contents
Description
Introduced in 1980 as Microsoft's first hardware product, it enables the Apple II to run the Digital Research CP/M operating system—then the industry-standard operating system for running business software—and many compilers and interpreters for several high-level languages on microcomputers. CP/M, one of the earliest cross-platform operating systems, is easily adaptable to a wide range of auxiliary chips and peripheral hardware, but it requires an Intel 8080-compatible CPU, which the Zilog Z80 is, but which the Apple's CPU, the MOS Technology 6502, is not.
This CP/M capability conferred by the Z80 SoftCard transformed the Apple II into a viable platform for running a much broader range of business software applications than had been possible until then.
History
The SoftCard was Paul Allen's idea and was developed by Tim Paterson of Seattle Computer Products (SCP) and Bill Gates and Don Burtis of Microsoft, after SCP developed the initial prototypes. Microsoft received most of its revenue from selling language compilers and interpreters for CP/M systems, which was before Microsoft's MS-DOS operating system (for Intel 8086-compatible processors as used by the IBM PC and other microcomputers) was introduced and became the company's best-selling product. A copy of the Microsoft BASIC programming language was included in the Softcard package. Unsure whether the card would sell, Microsoft first demonstrated it publicly at the West Coast Computer Faire in March 1980.
To Microsoft's surprise, the SoftCard was immediately successful. Although unprepared to take orders at the convention, a Microsoft executive accepted 1,000 business cards from those interested in purchasing the peripheral on the first day. 5,000 cards, a large number given the microcomputer market at the time, were purchased in the initial three months at $349 each, and the card sold well for several years. The SoftCard was the single most-popular platform to run CP/M, and Z-80 cards became very popular Apple II peripherals. Steve Ballmer stated during the Microsoft Surface reveal that the SoftCard was Microsoft's number one revenue source in 1980.
Microsoft also released a version for the Apple IIe, the Premium Softcard IIe.
Reception
InfoWorld in 1981 called the SoftCard "a fascinating piece of hardware". While criticizing the "computerese" of the CP/M documentation, the magazine wrote "if you need a lightweight, portable Z80 computer, the Apple/SoftCard combination is a perfect pair." BYTE wrote "Because of the flexibility that it offers Apple users, I consider the Softcard an excellent buy .. The price is reasonable, and it works".
InfoWorld in 1984 also favorably reviewed the Softcard IIe, approving of its ability to also replace the Extended 80-Column Text Card. The magazine concluded that it "is a good system among several good systems on the market", especially for those who wanted to run Microsoft BASIC or wanted functionality beyond CP/M.