Cromemco

From Wikipedia, the free encyclopedia

Cromemco was a Mountain View, California microcomputer company known for a series of high-end S-100 bus computers in the early days of the microcomputer revolution. Their machines were also known for generating computer graphics for television stations.

The company began as a partnership in 1974 between Harry Garland and Roger Melen, two Stanford PhD students. The name comes from their residence at Stanford University, Cro(thers) Mem(orial), a Stanford dormitory reserved for graduate students. The company was incorporated in 1976.

Their initial products used the Zilog Z80 microprocessor and the S-100 bus. The Z-1, released in August 1976, was a Z80 development system on a heavy-duty IMSAI 8080 22-slot chassis. It included 8 kB (KiB) of static RAM, an RS-232 serial port, and a PROM programmer, and sold for $2495. Its modular design supported a 4 MHz Z80 plug-in card ($395) and 4 kB static RAM cards ($295). The 1978 Z-2 line was an updated S-100 computer sold as modules or a complete system. The Z-2 was available with one 5 1/4 inch floppy disk drive and no RAM for $1995 or as the complete System Two (CS-2) with 64 kB RAM and two floppy drives for $3990. The Z-2 was the first commercially marketed microcomputer certified by the U.S. Navy for use aboard ships without major modification, and some were used aboard Ohio class submarines for data logging during tests. The System Three (CS-3) was the "professional" version of the System Two with two 8 inch floppy drives standard instead of 5 1/4 inch drives, and 32 kB RAM for $5990.

The Cromemco 3101 serial display terminal was a rebranded Beehive Medical Electronics B-100 terminal.

The System Two and System Three were sold to educational establishments across Europe and China. These sales helped the company to fund the transition to 16-bit systems with Motorola MC68000 processors during 1981. The System 1 followed the System Two and System Three. It contained either dual 5 1/4 inch floppy drives, or one floppy and a 5 MB hard disk, and was available with a dual processor "DPU" card which contained both Z80 and MC68000 processors. A ruggedized version of the MC68000 computer with removable hard disk cartridges was widely deployed by the USAF as part of the USAF Mission Support System (MSS) for F-16, F-15 and other aircraft. The MSS provided pilots key navigational and other data during missions and enabled combat pilots to compare mission effectiveness to flight plan data during the subsequent debriefing by their superiors.

The C-10 personal computer was introduced in June, 1982. It was a 4 MHz Z80 system featuring 64 KiB RAM with an 80 character × 25 line video screen for US$1785.

Cromemco produced the graphical microcomputers used by many television stations for weather forecasts during the mid to late 1980s. These Colorgraphics Systems were used on the evening news programs to replace the transparent acrylic glass maps on which local weathermen formerly drew weather symbols by hand. The computers used an enhanced version of Cromemco's popular Dazzler color graphics card.

The Z80 based systems ran either CDOS (Cromemco Disk Operating System) or CP/M.

Multi-user capability, via their own Cromix operating system based on Unix, was offered from 1979 onwards. Cromix was written in the C programming language to run on an 8 bit Z-80 processor. It included many of the properties of the Unix operating system which typically required a sixteen bit processor with a hardware memory mapper (that the Z-80 did not provide). The Z-80 processor was able to utilize up to 16 banks of 64 MB of RAM to support 1 MB multi user and multitasking applications. It was possible to run this efficient operating system using only a floppy disk drive (no hard disk) and that distinguished it from other operating systems of the time based on Unix which required large expensive hard drives. Roy Harrington was the lead designer of the Cromix development team.

The company employed, at its peak in 1983, more than 500 people and had annual revenues of US$55 million. It was wholly owned by Garland and Melen until it was sold to Dynatech in 1987 as a supplier to their subsidiary, Colorgraphics Weather Systems. The European division of Cromemco reorganized as Cromemco AG and is still in business.

1 Brochures and Advertisements
2 Eminent Cromemco Personnel
3 Systems
4 Peripherals
5 Cards
6 Innovations
7 Software Components
8 SUDS
9 See also
10 External links

[edit] Brochures and Advertisements

[edit] Eminent Cromemco Personnel

Dr Harry Garland - President of Cromemco
Dr Egon Zakrajsek - author of Cromix Plus
Ed Lupin - XXU Card Designer
Herb Lewis - Senior Engineer at Cromemco
Leigh Thomas - writer of Cromix a Users Guide
Professor Roger Melen - Cromemco cofounder
Richard Moore - Chief Executive officer Cromemco
Roger Sippl and Laura King - who built ISAM and Report Writer as Cromemco employees
Roy Harrington - writer of Z80 Cromix

[edit] Systems

Cromemco Z-1
Cromemco Z-2H
Cromemco C10
Cromemco SCC
Cromemco System Zero
Cromemco System One
Cromemco System Two
Cromemco System Three
Cromemco System CS100
Cromemco System CS200
Cromemco System CS300
Cromemco System CS400

[edit] Peripherals

Cromemco 3101
Cromemco 3102
Cromemco Maximizer

[edit] Cards

4FDC Floppy Disk Controller
4KZ 4KB Dynamic Memory
4PIO 4 Port IO Interface
8PIO 8 Port IO Interface
16FDC Floppy Disk Controller
16KPR Eprom Board
16KZ Dynamic RAM
64FDC Double Density Floppy Disk Controller
64KZ 64KB Dynamic RAM
256KZ 256KB Dynamic RAM
BIART Communications Processor
Bytesaver 8K PROM Programmer
D+7A IO Digital and Analog IO
DAZZLER TV Colour Graphics
DPU Dual Processing Unit
ESDC ESDI and SCSI Device Controller
IOP Input Output Processor
PRI Printer Interface
OCTART 8 channel Communications Processor
SDI Graphics Interface
STDC Intelligent ST506 Winchester Disk Controller
TUART Twin Universal Asynchronous Receiver Transmitter
WDI Winchester Disk Interface
XMM Memory Management
XMU HighSpeed Memory Management
XPU Dual Processor Unit
ZPU Zilog Z80A Processing Unit

XXU 68020 Dual Processor Unit

[edit] Innovations

Bank Switching
Cromix a UNIX like Operating System running on a Z80 Processor
Dual Processing
Pagingless Operating System
Persci Voice Coil Drives
Wide Bus

[edit] Software Components

This sections lists in some detail the system level software components used in Cromemco Systems

Cromemco Z-1 Monitor
Cromemco Z-80 Monitor
Cromemco CDOS version 1
Cromemco CDOS version 2
RDOS Initialisation and Bootstrapping Program
Z80 Cromix
68000 Cromix
XDOS Diagnostic and Bootstrap program for XXU
V2 UNIX

[edit] SUDS

The Software Update Service was a fee based subscription offering. After purchase of your software a SUDS subscription enabled you to obtain software updates usually supplied on 5.25 or 8 inch diskette together with a comprehensive update reference.

SUDS notes