The Z-80 SoftCard is a plug-in Apple II processor card developed by Microsoft to turn the computer into a CP/M system based upon the Zilog Z80 central processing unit (CPU). Becoming the most popular CP/M platform and Microsoft's top revenue source for 1980, it was eventually renamed the Microsoft SoftCard, and was succeeded by Microsoft's Premium Softcard IIe for the Apple IIe.

Z-80 SoftCard
Microsoft Softcard Z80 coprocessor for the Apple II
Release date1980; 43 years ago (1980)
Operating systemCP/M
PlatformApple II
SuccessorPremium Softcard IIe

Overview edit

Introduced in 1980 as Microsoft's first hardware product,[1] and bundled with the Microsoft BASIC programming language,[2] the Z-80 SoftCard is an Apple II processor card that enables the Apple II to run CP/M, an operating system from Digital Research. This gives Apple II users access to many more business applications, including compilers and interpreters for several high-level languages. 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.[3] The SoftCard has a Zilog Z80 CPU plus some 74LS00 series TTL chips to adapt that processor's bus to the Apple bus. As CP/M requires contiguous memory from address zero, which the Apple II doesn't have; addresses are translated in order to move non-RAM areas to the top of memory.[4]

History edit

The SoftCard was Paul Allen's idea.[5] Its original purpose was to simplify porting Microsoft's computer-language products to the Apple II.[6] The SoftCard was developed by Tim Paterson of Seattle Computer Products (SCP). SCP built prototypes,[7] Don Burtis of Burtronix redesigned the card, and California Computer Systems manufactured it for Microsoft.[8] Unsure whether the card would sell, Microsoft first demonstrated it publicly at the West Coast Computer Faire in March 1980.[2][6]

Microsoft also released a version for the Apple IIe, the Premium Softcard IIe. The card has functionality equivalent to the Extended 80-Column Text Card, including its 64 kB RAM, so would save money for users who wanted CP/M capability, additional memory, and 80-column text.[9]

Reception edit

Sales edit

The SoftCard's immediate success surprised Microsoft. Although unprepared to take orders at the West Coast Computer Faire, a Microsoft executive accepted 1,000 business cards from interested parties on the first day;[6] Compute! reported that the company was "inundated" with orders.[1] The SoftCard became the company's largest revenue source in 1980,[10] selling 5,000 units in three months at $349 each, with high sales continued for several years. For a while, the SoftCard was the single most-popular platform to run CP/M,[11] and Z-80 cards became very popular Apple II peripherals.[12] By 1981 Microsoft, Lifeboat Associates, and Peachtree Software published their CP/M software on Apple-format disks.[8]

Critical reception edit

Compute! witnessed the SoftCard's debut in March 1980 at the West Coast Computer Faire, calling it "an Apple breakthru".[1] 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."[3] 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".[8]

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.[9]

Alternatives edit

Following Microsoft's success, several other companies developed Z80 cards for the Apple II as well, including Digital Research with Apple CP/M [de] and a CP/M card developed by Advanced Logic Systems named "The CP/M Card" (with a 6 MHz Z80 and 64 kB RAM) and Digital Research's CP/M Gold Card for CP/M Pro 3.0 (with 64 or 192 kB RAM).[13][14] Others independent designs came from Applied Engineering, PCPI (with their 6 MHz Appli-Card), Cirtech, IBS. There were also about a dozen SoftCard clone manufacturers.

References edit

  1. ^ a b c Lock, Robert (May–June 1980). "An Apple Breakthru". Compute!. No. 4. Small Systems Services. p. 6. ISSN 0194-357X. OCLC 637460999. Retrieved October 25, 2013.
  2. ^ a b "Z-80 Board Puts CP/M on Apple". InfoWorld. Popular Computing. 2 (6): 3. April 28, 1980. ISSN 0199-6649.
  3. ^ a b Hogan, Thom (March 3, 1981). "Microsoft's Z80 SoftCard". InfoWorld. Popular Computing. 3 (4): 20–21. ISSN 0199-6649.
  4. ^ "Apple II Softcard CP/M Reference". Retrieved August 14, 2020.
  5. ^ Raburn, Vern (October 20, 1980). "Letters: Developed by Microsoft". Computerworld. 14 (43): 37. ISSN 0010-4841. It was one of the founders of Microsoft, Paul Allen, who hit upon the idea of putting a Z80 processor into the Apple.
  6. ^ a b c "Seminar Spills Negotiating Secrets". InfoWorld. Popular Computing. 2 (21): 24. November 24, 1980. ISSN 0199-6649. Unsure of the demand for the product, Microsoft took a prototype to the last West Coast Computer Faire
  7. ^ Freiberger, Paul; Swaine, Michael (2000). Fire in the Valley: The Making of the Personal Computer. New York, NY: McGraw-Hill. p. 329. ISBN 0-07-135892-7. They brought in Tim Paterson of Seattle Computer Products, located across Lake Washington, to try to build a card for the Apple that would let it run Microsoft's 8080 and Z80 software. They called it the SoftCard. Paterson did a series of prototypes before Don Burdis took over the project.
  8. ^ a b c Pelczarski, Mark (November 1981). "Microsoft Softcard". BYTE. pp. 152–162. Retrieved October 19, 2013.
  9. ^ a b Petersen, Marty (February 6, 1984). "Premium Softcard IIe". InfoWorld. pp. 64, 66. Retrieved January 25, 2015.
  10. ^ Ballmer, Steve. "Microsoft Surface Keynote". YouTube. Archived from the original on December 19, 2021. Retrieved June 19, 2012.
  11. ^ Bunnell, David (February–March 1982). "The Man Behind The Machine? / A PC Exclusive Interview With Software Guru Bill Gates". PC Magazine. p. 16. Retrieved February 17, 2012.
  12. ^ Markoff, John (May 1984). "The Apple IIc Personal Computer". BYTE. p. 282. Retrieved October 23, 2013.
  13. ^ "CP/M Gold Card | 102645991". Computer History Museum. 1984.
  14. ^ Wheelwright, Geof (June 16, 1984). "Golden Opportunity". Personal Computer News. pp. 23–24. Retrieved March 3, 2023.

External links edit

  • AppleLogic website, showing peripheral cards for the Apple II series of computers, including the Microsoft Softcard