
The Cromemco Dazzler was a
graphics card
A graphics card (also called a video card, display card, graphics adapter, VGA card/VGA, video adapter, display adapter, or mistakenly GPU) is an expansion card which generates a feed of output images to a display device, such as a computer mo ...
for
S-100 bus
The S-100 bus or Altair bus, IEEE 696-1983 ''(withdrawn)'', is an early computer bus designed in 1974 as a part of the Altair 8800. The bus was the first industry standard expansion bus for the microcomputer industry. computers, consisting of ...
computers introduced in a ''
Popular Electronics
''Popular Electronics'' was an American magazine published by John August Media, LLC, and hosted at TechnicaCuriosa.com. The magazine was started by Ziff-Davis Publishing Company in October 1954 for electronics hobbyists and experimenters. It so ...
'' cover story in 1976.
[Les Solomon]
"Solomon's Memory"
, in ''Digital Deli'', Workman Publications, 1984, It was the first color graphics card available for
microcomputer
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 (P ...
s.
[Harry Garland]
"Ten years and counting"
''Creative Computing'', Volume 10, Number 11 (November 1984), pg. 104 The Dazzler was the first of a succession of increasingly capable graphics products from
Cromemco
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.
The company began as a partnership in 1974 between Harry Ga ...
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.
History
The Dazzler came about in a roundabout fashion after Les Solomon, Technical Editor for ''
Popular Electronics
''Popular Electronics'' was an American magazine published by John August Media, LLC, and hosted at TechnicaCuriosa.com. The magazine was started by Ziff-Davis Publishing Company in October 1954 for electronics hobbyists and experimenters. It so ...
'' magazine, demonstrated the original
Altair 8800
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU. Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics and was sold by mail order through advertisemen ...
to
Roger Melen of
Stanford University. After seeing it, Melen purchased Altair #2 for his friend
Harry Garland to work with. The two built a number of add-ons for the machine, collaborating with Terry Walker on the design of the first digital camera called the
Cyclops
In Greek mythology and later Roman mythology, the Cyclopes ( ; el, Κύκλωπες, ''Kýklōpes'', "Circle-eyes" or "Round-eyes"; singular Cyclops ; , ''Kýklōps'') are giant one-eyed creatures. Three groups of Cyclopes can be distinguish ...
and then moving on to the Dazzler.
[ The Dazzler was first shown at the Homebrew Computer Club on November 12, 1975.]
Like many early microcomputer projects of the era, the Dazzler was originally announced as a self-built kit in ''Popular Electronics''. In order to "kick start" construction, they offered kits including a circuit board
A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a laminated sandwich stru ...
and the required parts, which the user would then assemble on their own. This led to sales of completely assembled Dazzler systems, which became the only way to purchase the product some time after. Sales were so fruitful that Melen and Garland formed Cromemco
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.
The company began as a partnership in 1974 between Harry Ga ...
to sell the Dazzler and their other Altair add-ons, selecting a name based on Crothers Memorial Hall, their residence while attending Stanford.
When Federico Faggin
Federico Faggin (, ; born 1 December 1941) is an Italian physicist, engineer, inventor and entrepreneur. He is best known for designing the first commercial microprocessor, the Intel 4004. He led the 4004 (MCS-4) project and the design group d ...
's new company - Zilog
Zilog, Inc. is an American manufacturer of microprocessors and 8-bit and 16-bit microcontrollers. It is also a supplier of application-specific embedded system-on-chip (SoC) products.
Its most famous product is the Z80 series of 8-bit microp ...
- introduced the Z80
The Z80 is an 8-bit microprocessor introduced by Zilog as the startup company's first product. The Z80 was conceived by Federico Faggin in late 1974 and developed by him and his 11 employees starting in early 1975. The first working samples were ...
, Cromemco branched out into their own line of Z80-based S-100 compatible computers almost immediately. Over time these became the company's primary products. Combinations of their rackmount
A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is wide. The 19 inch dimension includes the edges or "ears" that protrude from each side of the equ ...
machines and the Dazzler formed the basis of ColorGraphics Weather Systems (CWS) product line into the late 1980s, and when CWS was purchased by Dynatech in 1987, Dynatech also purchased Cromemco to supply them.[
]
Dazzler software
The original advertisement for the Dazzler offered three different software programs for sale (provided on punched paper tape.) These were ''Conway's Game of Life
The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is a zero-player game, meaning that its evolution is determined by its initial state, requiring no furt ...
'', Dazzlewriter (an alphanumeric display) and a colorful pattern-generating program, Kaleidoscope.
The cover of the June 1976 issue of ''Byte
The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit ...
'' magazine shows a Dazzler image from ''Conway's Game of Life'', and credits Ed Hall as author of the Game of Life software for the Dazzler. ''Byte'' also credits Steve Dompier with authoring the animation tool "Dazzlemation" and the first animation made with Dazzlemation calle
"Magenta Martini"
George Tate (who later co-founded Ashton-Tate) is credited with a Tic-Tac-Toe game for the Dazzler, and Li-Chen Wang
Li-Chen Wang (born 1935) is an American computer engineer, best known for his ''Palo Alto Tiny BASIC'' for Intel 8080-based microcomputers. He was a member of the Homebrew Computer Club and made significant contributions to the software for early ...
is credited as the author of
Kaleidoscope
. Ed Hall's color realization of Conway's Game of Life
The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is a zero-player game, meaning that its evolution is determined by its initial state, requiring no furt ...
led to a revival of interest in the game.
Stan Veit, owner of the Computer Mart of New York, described the reaction when he displayed the changing patterns of Kaleidoscope on a color television in his store window at the corner of 5th Avenue and 32nd Street in New York City in early 1976. “People driving by began to stop and look – they had never seen anything like it before. In a short time the Dazzler had caused a traffic jam on 5th Avenue!” The police had to contact the building landlord and make him disconnect the television.
Over time, Cromemco introduced additional software for the Dazzler, at first on paper tape
Five- and eight-hole punched paper tape
Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop
Punched tape or perforated paper tape is a form of data storage ...
and later floppy disk
A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined ...
, including ''Spacewar!
''Spacewar!'' is a space combat video game developed in 1962 by Steve Russell in collaboration with Martin Graetz, Wayne Wiitanen, Bob Saunders, Steve Piner, and others. It was written for the newly installed DEC PDP-1 minicomputer at the Mas ...
'' in October 1976. Cromemco customers also developed software for a wide range of graphics applications, from monitoring the manufacturing processes at a coffee factory in Columbia to displaying real-time images of heart blood flow, generated through cardiac radionuclide imaging, in Scotland.
Dazzler hardware
The Dazzler used over 70 MOS and TTL ICs, which required two cards to hold all the chips, "Board 1" held the analog circuits, while "Board 2" held the bus interface and digital logic. The two cards were connected together with a 16-conductor ribbon cable. Although the analog card did not talk on the bus, it would normally be plugged into the bus for power connections and physical support within the chassis. The manual also described a way to "piggyback" the two cards with a separate power cable to save a slot. Output from the analog card was composite color, and an RF modulator
An RF modulator (or radio frequency modulator) is an electronic device whose input is a baseband signal which is used to modulate a radio frequency source.
RF modulators are used to convert signals from devices such as media players, VCRs an ...
was available for direct connection to a color TV.
The Dazzler lacked its own frame buffer
A framebuffer (frame buffer, or sometimes framestore) is a portion of random-access memory (RAM) containing a bitmap that drives a video display. It is a memory buffer containing data representing all the pixels in a complete video frame. Moder ...
, accessing the host machine's main memory
Computer data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers.
The central processing unit (CPU) of a comput ...
using a custom DMA
DMA may refer to:
Arts
* ''DMA'' (magazine), a defunct dance music magazine
* Dallas Museum of Art, an art museum in Texas, US
* Danish Music Awards, an award show held in Denmark
* BT Digital Music Awards, an annual event in the UK
* Doctor of M ...
controller that provided 1 Mbit/s throughput. The card read data from the computer at speeds that demanded the use of SRAM memory, as opposed to lower cost DRAM
Dynamic random-access memory (dynamic RAM or DRAM) is a type of random-access semiconductor memory that stores each bit of data in a memory cell, usually consisting of a tiny capacitor and a transistor, both typically based on metal-oxi ...
s. Control signals and setup was sent and received using the S-100 bus's input/output "ports", normally mapped to 0E and 0F. 0E contained an 8-bit address pointing to the base of the frame buffer in main memory, while 0F was a bit-mapped control register with various setup information.
The Dazzler supported four graphics modes in total, selected by setting or clearing bits in the control register (0F) that controlled two orthogonal selections. The first selected the size of the frame buffer, either 512 bytes or 2 kB. The other selected normal or "X4" mode, the former using 4-bit nybbles packed 2 to a byte in the frame buffer to produce an 8-color image, or the latter which was a higher resolution monochrome mode using 1-bits per pixel, 8 to a byte. Selecting the mode indirectly selected the resolution. In normal mode with a 512 byte buffer there would be 512 bytes × 2 pixels per byte = 1,024 pixels, arranged as a 32 by 32 pixel image. A 2 kB buffer produced a 64 by 64 pixel image, while the highest resolution used a 2 kB buffer in X4 mode to produce a 128 by 128 pixel image. In normal mode the color was selected from a fixed 8-color palette with an additional bit selecting intensity ( 4-bit RGBI), while in X4 mode the foreground color was selected by setting three bits in the control register to turn on red, green or blue (or combinations) while a separate bit controlled the intensity.
Super Dazzler
In 1979, Cromemco replaced the original Dazzler with the Super Dazzler. The Super Dazzler Interface (SDI) had 756 x 484 pixel resolution with the ability to display up to 4096 colors ( 12-bit RGB), a capability that had previously only been available in much more expensive systems. Dedicated two-port memory cards were used for image storage for higher performance. While the original Dazzler had a composite video
Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channe ...
output signal, the new SDI used separate RGB component video
Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compo ...
outputs for higher resolution. The SDI also had the ability to be synchronized to other video equipment. Cromemco systems with the SDI board became the systems of choice for television broadcast applications, and were widely deployed by the United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army S ...
as Mission Support Systems.
See also
*
* MicroAngelo
SCION's MicroAngelo was an early graphics card for S-100 bus computers. Each MicroAngelo board produced a 512 by 480 pixel monochrome image, high resolution for the era.Most home computers of the era displayed 256 to 320 by 192 to 240, while the ...
, a higher-resolution system for S-100 computers
* Matrox
Matrox Graphics, Inc. is a producer of video card components and equipment for personal computers and workstations. Based in Dorval, Quebec, Canada, it was founded in 1976 by Lorne Trottier and Branko Matić. The name is derived from "Ma" in ...
, Matrox's first graphics product was a video card for S-100 machines, the ALT-256
* VDM-1 The Processor Technology VDM-1, for Video Display Module, was the first video card for S-100 bus computers. Created in 1975, it allows an S-100 machine to produce its own display, and when paired with a keyboard and their 3P+S card, it eliminate ...
, a text-only display that was the first interface for S-100 machines
References
{{reflist, 30em
External links
Saga of a System
- David Ahl's story of how he got his Altair 8800/Dazzler system built, includes some sample images
- image of the original design and its instruction manual
Build the TV Dazzler
- original ''Popular Electronics'' article
Computer-related introductions in 1976
Dazzler
History of computing hardware
Graphics cards
S-100 graphics cards