Cromemco Z-2

Last updated
Cromemco Z-2
Cromemco Z-2 Computer.jpg
Cromemco Z-2 CPU unit and terminal
Developer Cromemco
Type Microcomputer
Release date1977;47 years ago (1977)
Operating system CP/M, Cromemco DOS
CPU Zilog Z80
Cromemco Z2 advertisement, July 1977 Cromemco Z2 Ad July 1977.jpg
Cromemco Z2 advertisement, July 1977

Z-2 is a series of microcomputers made by Cromemco, Inc. which were introduced to the market in the middle to late 1970s. They were S-100 bus machines powered by the Zilog Z80 processor and typically ran on the CP/M operating system.

Contents

They were originally available in assembled or kit form to serve both a commercial market and the computer enthusiast market. Later the machines were only available factory-assembled. The machines were widely respected for their speed, configurability, durability, and reliability. [1] [2] [3] [4]

The Z-2 was a Z80–based microcomputer system that was introduced in 1977. The original Z-2 in kit form included a ZPU-K Z80 CPU card, S-100 bus motherboard, all-metal rack-mount chassis and dust case, card socket and card guide; the assembled form included a complete set of sockets and card guides, and a cooling fan. The Z-2 series was capable of supporting up to 21 S-100 boards and could be configured with any of the boards supplied by Cromemco. [5]

The Z-2 gave an impression of solidity due to its hefty 450-watt power supply and heavy metal chassis. A TU-ART (dual serial and parallel board), 4FDC Floppy Disk Controller, one or more 16KZRAM cards, and a Wangco 5¼" floppy disk drive would be added to form a basic system.

An unusual feature of the Z-2 was switch–selectable CPU speed; 250 or 500 nanosecond cycle time were available. The ZPU speed was 4 MHz at a time when less than 2 MHz was normal, and boards from other manufacturers might still require the slower speed. The ZPU card in the Z-2 could address up to 64 kilobytes (65,536 bytes) of RAM. However, the 16KZ memory card supported bank-switching with 8 banks of 64 kilobytes each. When using the 16KZ, the maximum RAM of the Z-2 was limited by the available S-100 slots. If 16 of the slots were occupied by 16KZ cards, then the system had 4 banks of 64 kilobytes each, for a total of 256 kilobytes (262,144 bytes).

Additional S-100 slots were required for cards controlling peripherals, disk drives, and I/O interfaces. Communication with the processor was normally performed through a TU-ART or other S-100 bus compatible interface card, which could run a CRT terminal or teletype.

Cromemco Z-2D

The Cromemco Z-2D computer was a Z80–based microcomputer system which differed from a Z-2 by having one or two Wangco 5¼" disk drives, a disk power supply and a 4FDC disk controller in a Z-2 chassis. The Z-2D was available in assembled and kit form. The Z-2D was also called the "System Two". [6]

Cromemco Z-2H

Cromemco Z-2D computer with optional HDD hard disk drive providing up to 22 megabytes of storage (1980) Cromemco Z-2D with HDD 1980.jpg
Cromemco Z-2D computer with optional HDD hard disk drive providing up to 22 megabytes of storage (1980)

The Cromemco Z-2H computer was based on the Z-2D, but in addition had an 11 megabyte internal hard disk drive. [7] While the Z-2 and Z-2D had 21 S-100 slots, the Z-2H was limited to 12 expansion slots due to the size of the internal hard disk. Over 1000 Z-2H systems were sold in the first six months on the market. [2] The 11-megabyte hard disks were also offered as a separate unit, the HDD, that could be used with a Z-2D computer. The HDD came with either one or two hard disks, for up to 22 megabytes of storage. [8]

Cromemco Z-2 Microcomputer Systems
SystemYear IntroducedS-100 slotsInternal Floppy DiskInternal Hard Disk
Z-2197721n/an/a
Z-2D1978212 x 5-inchn/a
Z-2H1979122 x 5-inch11 megabytes

Notable installations

The Chicago Mercantile Exchange (CME) adopted Cromemco Z-2 microcomputers as the backbone of the CME trading floor, employing a total of 60 Z-2 systems. [9] For a 10-year period every trade at the CME was processed by these Cromemco systems. In 1992 the Cromemco systems were replaced by IBM PS/2 computers. [10]

Cromemco Z-2 System with removable hard disk was deployed worldwide by the United States Air Force (1986). Cromemco USAF Z-2 System for F-16.jpg
Cromemco Z-2 System with removable hard disk was deployed worldwide by the United States Air Force (1986).

Z-2 computers were well-suited for data acquisition and analysis applications. One example was work in profiling the deceleration of trains during braking in the San Francisco Bay Area Rapid Transit (BART) system during actual operation. Cromemco Z-2D computers were employed both for data acquisition and analysis to develop an exact model of the braking profile under a variety of track conditions and train loadings. [11]

In 1979 the United States Navy (at the Applied Physics Laboratory) used a Cromemco Z-2 computer to generate speech output for the Aegis Combat System in the Combat Information Center. [12]

The United States Air Force deployed 600 Cromemco Systems from 1985 to 1996 as Mission Support Systems for the F-15, F-16, and F-111 aircraft. [13] [14] During this period Cromemco systems were used for the planning of every combat mission for these aircraft, including missions during the First Gulf War. These systems were based on the Cromemco Z-2 computer, but utilized the Motorola 68020 32-bit processor, and had a custom, removable hard drive to meet the Air Force need to be able to physically secure all flight plan information. Cromemco received a patent on this technology. [15]

Related Research Articles

<span class="mw-page-title-main">Microcomputer</span> Small computer with a CPU made out of a microprocessor

A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive. Many microcomputers are also personal computers. An early use of the term "personal computer" in 1962 predates microprocessor-based designs. (See "Personal Computer: Computers at Companies" reference below). A "microcomputer" used as an embedded control system may have no human-readable input and output devices. "Personal computer" may be used generically or may denote an IBM PC compatible machine.

<span class="mw-page-title-main">Macintosh II</span> First model of the second generation of the Apple Macintosh computer line

The Macintosh II is a personal computer designed, manufactured, and sold by Apple Computer from March 1987 to January 1990. Based on the Motorola 68020 32-bit CPU, it is the first Macintosh supporting color graphics. When introduced, a basic system with monitor and 20 MB hard drive cost US$5,498. With a 13-inch color monitor and 8-bit display card the price was around US$7,145. This placed it in competition with workstations from Silicon Graphics, Sun Microsystems, and Hewlett-Packard.

IBM manufactured magnetic disk storage devices from 1956 to 2003, when it sold its hard disk drive business to Hitachi. Both the hard disk drive (HDD) and floppy disk drive (FDD) were invented by IBM and as such IBM's employees were responsible for many of the innovations in these products and their technologies. The basic mechanical arrangement of hard disk drives has not changed since the IBM 1301. Disk drive performance and characteristics are measured by the same standards now as they were in the 1950s. Few products in history have enjoyed such spectacular declines in cost and physical size along with equally dramatic improvements in capacity and performance.

<span class="mw-page-title-main">Rainbow 100</span> DEC microcomputer

The Rainbow 100 is a microcomputer introduced by Digital Equipment Corporation (DEC) in 1982. This desktop unit had a monitor similar to the VT220 and a dual-CPU box with both 4 MHz Zilog Z80 and 4.81 MHz Intel 8088 CPUs. The Rainbow 100 was a triple-use machine: VT100 mode, 8-bit CP/M mode, and CP/M-86 or MS-DOS mode using the 8088. It ultimately failed to in the marketplace which became dominated by the simpler IBM PC and its clones which established the industry standard as compatibility with CP/M became less important than IBM PC compatibility. Writer David Ahl called it a disastrous foray into the personal computer market. The Rainbow was launched along with the similarly packaged DEC Professional and DECmate II which were also not successful. The failure of DEC to gain a significant foothold in the high-volume PC market would be the beginning of the end of the computer hardware industry in New England, as nearly all computer companies located there were focused on minicomputers for large organizations, from DEC to Data General, Wang, Prime, Computervision, Honeywell, and Symbolics Inc.

<span class="mw-page-title-main">North Star Horizon</span>

The North Star Horizon was a popular 8-bit S-100 bus computer introduced in October 1977. Like most S-100 machines of the era, it was built around the Zilog Z80A microprocessor, and typically ran the CP/M operating system. It was produced by North Star Computers, and it could be purchased either in kit form or pre-assembled. The North Star Horizon was one of the first computers to have built in floppy drives as well as being one of the first personal computers to have a hard disk drive.

Shepardson Microsystems, Inc. (SMI) was a small company producing operating systems and programming languages for CP/M, the Atari 8-bit family and Apple II computers. SMI is most noted for the original Apple II disk operating system, Atari BASIC, and Atari's disk operating system. Shepardson Microsystems was founded by Robert Shepardson in Saratoga Springs, New York.

<span class="mw-page-title-main">Disk II</span> Floppy disk drive for the Apple II computer

The Disk II Floppy Disk Subsystem, often rendered as Disk ][, is a 5 +1⁄4-inch floppy disk drive designed by Steve Wozniak at the recommendation of Mike Markkula, and manufactured by Apple Computer, Inc. It went on sale in June 1978 at a retail price of US$495 for pre-order; it was later sold for $595 including the controller card and cable. The Disk II was designed specifically for use with the Apple II personal computer family to replace the slower cassette tape storage. These floppy drives cannot be used with any Macintosh without an Apple IIe Card as doing so will damage the drive or the controller.

<span class="mw-page-title-main">Zenith Z-89</span> Personal computer produced by Zenith Data Systems

The Z-89 is a personal computer introduced in 1979 by Heathkit, but produced primarily by Zenith Data Systems (ZDS) in the early 1980s. It combined an updated version of the Heathkit H8 microcomputer and H19 terminal in a new case that also provided room for a built-in floppy disk on the right side of the display. Based on the Zilog Z80 microprocessor it is capable of running CP/M as well as Heathkit's own HDOS.

<span class="mw-page-title-main">Power Macintosh 5500</span> Personal computer by Apple Computer

The Power Macintosh 5500 is a personal computer designed, manufactured, and sold by Apple Computer from February 1997 to March 1998. Like the Power Macintosh 5260 and 5400 that preceded it, the 5500 is an all-in-one design, built around a PowerPC 603ev processor operating at 225, 250 or 275 megahertz (MHz).

<span class="mw-page-title-main">Hardcard</span>

Hardcard is the genericized trademark for a hard disk drive, disk controller, and host adapter on an expansion card for a personal computer.

<span class="mw-page-title-main">Cromemco 4FDC</span>

The Cromemco 4FDC Floppy Disk Controller is designed to interface both 5.25- and 8.0-inch floppy disk drives to the S-100 computer bus used in Cromemco and other IEEE 696 computers. It also contains an RS-232 serial I/O channel with software-selectable baud rates from 110 to 76,800. In addition, it has a 1 KB resident 2708 ROM containing Cromemco's RDOS, the resident disk operating system.

George Morrow was part of the early microcomputer industry in the United States. Morrow promoted and improved the S-100 bus used in many early microcomputers. Called "one of the microcomputer industry's iconoclasts" by Richard Dalton in the Whole Earth Software Catalog, Morrow ran his own computer business, Thinker Toys, Inc., later Morrow Designs. He was also a member of the Homebrew Computer Club.

Cromemco was a Mountain View, California microcomputer company known for its high-end Z80-based S-100 bus computers and peripherals in the early days of the personal computer revolution.

<span class="mw-page-title-main">Heathkit H8</span>

Heathkit's H8 is an Intel 8080A-based microcomputer sold in kit form starting in 1977. The H8 is similar to the S-100 bus computers of the era, and like those machines is often used with the CP/M operating system on floppy disk.

<span class="mw-page-title-main">Cromemco Dazzler</span>

The Cromemco Dazzler was a graphics card for S-100 bus computers introduced in a Popular Electronics cover story in 1976. It was the first color graphics card available for microcomputers. The Dazzler was the first of a succession of increasingly capable graphics products from Cromemco which, by 1984, were in use at 80% of all television stations in the U.S. for the display of weather, news, and sports graphics.

<span class="mw-page-title-main">Cromemco Bytesaver</span>

The Bytesaver, introduced by Cromemco in 1976, was the first programmable memory board for the MITS Altair and S-100 bus microcomputer systems. The Bytesaver had sockets for 8 UV-erasable EPROMs providing up to 8 Kbytes of storage. The EPROMs could be programmed by the Bytesaver, or read as computer memory. In the history of microcomputer systems, the Bytesaver was the first viable alternative to the use of punched paper tape for storing programs, and has been called “a great advance in microcomputer technology”.

PolyMorphic Systems was a manufacturer of microcomputer boards and systems based on the S-100 bus. Their products included the Poly-88 and the System 8813. The company was incorporated in California in 1976 as Interactive Products Corporation d/b/a PolyMorphic Systems. It was initially based in Goleta, then Santa Barbara, California.

The Z80 Operating System with Relocatable Modules and I/O Management (Z80-RIO) is a general-purpose operating system developed by Zilog in the late 1970s for various computer systems including the Z80 Micro Computer System (MCZ-1) series and the Z80 Development System (ZDS). The MCZ systems were primarily used for software development and automation solutions. RIO was designed to facilitate the development and integration of user's programs into a production environment.

<span class="mw-page-title-main">Dimension 68000</span> Microcomputer introduced by the Micro Craft Corporation in 1983

The Dimension 68000 is a microcomputer introduced by the Micro Craft Corporation in 1983 that sought to emulate the Apple II, the IBM PC, and various CP/M-centric computers through a family of coprocessor expansion cards and emulation software. The Dimension 68000 can also run as a standalone computer based on the Motorola 68000 from which it gets its namesake. The computer is mostly the brainchild of Mike Carpenter, a former executive of a scientific instrument manufacturer who incorporated Micro Craft in Dallas, Texas, to develop the Dimension 68000. It had a market lifespan of three years and received mixed, mostly positive, reception from the technology press. Criticism was leveled at the $6,250 price tag for the computer with the full deck of coprocessor cards, as well as the extent of the emulation power of those cards.

References

  1. ↑ Veit, Stan (1993). "Cromemco: Innovation and Reliability". Stan Veit's History of the Personal Computer. Asheville, North Carolina: WorldComm. pp. 103–112. ISBN   1-56664-023-7. It was said that circus elephants could stand on the Z-2 without damaging it.
  2. 1 2 The Association of Computer Users (April 1980). "Cromemco's System Two and Z-2H". Benchmark Report. 3.1 (4).
  3. ↑ Warren, Jim (7 February 1979). "Report on Outstanding Cromemco Reliability". Intelligent Machines Journal (2): 4.
  4. ↑ Stevens, Richard (February 1979). "Cromemco Z-2D under the microscope: Construction never less than excellent". Practical Computing. 2 (2). Retrieved 3 March 2013.
  5. ↑ Cromemco Z-2 Instruction Manual, Cromemco, Inc. Part No. N/A, 1977
  6. ↑ Cromemco Z-2D Instruction Manual, Cromemco, Inc. Part No. 0023-0014, 1978
  7. ↑ "Z-2H Brochure". Cromemco. Retrieved 3 March 2013.
  8. ↑ "HDD Disk Memory System Brochure". Cromemco. Retrieved 3 March 2013.
  9. ↑ Breeding, Gary (January–February 1984). "Cromemco Systems Network Transactions at Chaotic Exchange". I/O News. 3 (6): 20. ISSN   0274-9998.
  10. ↑ "CME Taps Datacode To Distribute Quotation Data To Floor Traders". WatersTechnology. 27 January 1992. Retrieved 3 March 2013.
  11. ↑ G. Rothbart; R. Fullwood; H. O. Conde (4–6 December 1978). "Automatic data acquisition and processing of train deceleration for rapid transit train systems". Proceedings of the 1978 annual conference on - ACM '78. Vol. 2. pp. 612–616. doi:10.1145/800178.810098. ISBN   0897910001. S2CID   7206107 . Retrieved 3 March 2013.
  12. ↑ Sterne, D.F. "Tactical Speech Synthesis" (PDF). Defence Technical Information Center. pp. 64–66. Archived (PDF) from the original on February 11, 2017. Retrieved 18 July 2018.
  13. ↑ Kuhman, Robert. "The Cro's Nest RCP/M-RBBS". www.kuhmann.com. Archived from the original on 10 February 2012. Retrieved 10 February 2012.
  14. ↑ "Mission Support". Aviation Week & Space Technology . 126 (22): 105. 1 June 1987.
  15. ↑ "U.S. Patent #4,870,605". USPTO.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.