Processor Technology Corporation was a personal computer company founded in April 1975 by Gary Ingram and Bob Marsh in
Berkeley, California
Berkeley ( ) is a city on the eastern shore of San Francisco Bay in northern Alameda County, California, United States. It is named after the 18th-century Irish bishop and philosopher George Berkeley. It borders the cities of Oakland and Emer ...
. Their first product was a 4K byte RAM board that was compatible with the
MITS 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 advertiseme ...
computer but more reliable than the MITS board.
[, ](_blank)
/ref> This was followed by a series of memory and I/O boards including a video display module.[ A Processor Technology advertisement showing a motherboard with eight add-in boards.]
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 soo ...
magazine wanted a feature article on an intelligent computer terminal and Technical Editor Les Solomon asked Marsh and Lee Felsenstein
Lee Felsenstein (born April 27, 1945) is an American computer engineer who played a central role in the development of the personal computer. He was one of the original members of the Homebrew Computer Club and the designer of the Osborne 1, the ...
to design one. It was featured on the July 1976 cover and became the Sol-20
The Sol-20 was the first fully assembled microcomputer with a built-in keyboard and television output, what would later be known as a home computer. The design was a combination of an Intel 8080-based motherboard, a VDM-1 graphics card, the 3P+S ...
Personal Computer. The first units were shipped in December 1976 and the Sol-20 was a very successful product. The company failed to develop next generation products and ceased operations in May 1979.[Freiberger (2000), 153-155]
History
Bob Marsh, Lee Felsenstein
Lee Felsenstein (born April 27, 1945) is an American computer engineer who played a central role in the development of the personal computer. He was one of the original members of the Homebrew Computer Club and the designer of the Osborne 1, the ...
and Gordon French
Gordon French (March 7, 1935 - October 26, 2019) was an American computer engineer and programmer who played a key role in the Homebrew Computer Club. He died on October 26, 2019, in Roseburg, Oregon.
On March 5, 1975, Gordon French hosted the ...
started designing the Sol-20 between April and July 1975. The Sol-20 utilized the Intel 8080
The Intel 8080 (''"eighty-eighty"'') is the second 8-bit microprocessor designed and manufactured by Intel. It first appeared in April 1974 and is an extended and enhanced variant of the earlier 8008 design, although without binary compatibil ...
8-bit microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
chip, running at 2 MHz. A major difference between the Sol-20 and most other machines of the era was its built-in video driver, which allowed it to be attached to a composite monitor
A composite monitor or composite video monitor is any analog video display that receives input in the form of an analog composite video signal to a defined specification. A composite video signal encodes all information on a single conductor; a ...
for display. The Sol-20 consisted of a main motherboard
A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expand ...
(PCB) mounted at the bottom of the case, and a five slot 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 ...
card cage. The main PCB consisted of the CPU, memory, video display, I/O circuits. Inside the case included power supply, fan, and keyboard. The case was painted 'IBM blue' and the sides of the case were made of solid oiled walnut originally salvaged from a gun stock manufacturer.
Processor Technology manufactured approximately 10,000 Sol-20 personal computers between 1977 and 1979. All Processor Technology products were available either fully assembled, or as electronic kit
An electronic kit is a package of electrical components used to build an electronic device. Generally, kits are composed of electronic components, a circuit diagram (schematic), assembly instructions and often a printed circuit board (PCB) or ...
s. Processor Technology also sold software on Compact Cassette
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Ottens ...
. One side of the tape was recorded in CUTS format, and the other side was Kansas City standard
The Kansas City standard (KCS), or ''Byte'' standard, is a data storage protocol for standard cassette tapes at . It originated in a symposium sponsored by Byte (magazine), ''Byte'' magazine in November 1975 in Kansas City, Missouri to develop a ...
format. Gary Ingram and Steven Dompier wrote the original software utilities. Lee Felsenstein wrote the original user manuals as a contractor.
Standards
Processor Technology also designed several S-100 bus boards. The boards were meant to be compatible with the circuits of Sol-20.
The Video Display Module 1 (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 eliminates ...
) was the original video display interface for S-100 bus systems.[ Processor Technology advertisement. The VDM-1 Video Display Module for the Altair computer generated 16 lines of 64 characters on a black and white TV. Kit price was $160, assembled $225. The Cromemco TV Dazzler first appeared in the April 1976 issue of Byte] The board generates sixteen 64-character lines of upper and lower case typeface on any standard 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 channels) a ...
monitor or a modified TV set. Utilizing a 1,024 byte (1K) segment of system memory, the VDM-1 provided memory-mapped I/O
Memory-mapped I/O (MMIO) and port-mapped I/O (PMIO) are two complementary methods of performing input/output (I/O) between the central processing unit (CPU) and peripheral devices in a computer. An alternative approach is using dedicated I/O pro ...
for high performance, and also included hardware support for scrolling. The VDM-1 Video Board was a great improvement over using a teletype machine
A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Initia ...
or a serial attached terminals, and was popular for owners of other S-100 bus systems such as the IMSAI 8080
The IMSAI 8080 was an early microcomputer released in late 1975, based on the Intel 8080 and later 8085 and S-100 bus. It was a clone of its main competitor, the earlier MITS Altair 8800. The IMSAI is largely regarded as the first "clone" micr ...
.
Another popular product was the CUTS Tape I/O Interface S-100 board. The CUTS board offered standard interface for saving and reading data from cassette tape, supporting both the Kansas City standard format, as well as their own custom CUTS format. Lee Felsenstein was key participant of the development of Kansas City standard format, the first cross-system data transfer standard for microcomputers.
Products
* Computers
** Sol-PC — Single circuit board only without case or power supply; available as fully assembled or as kit form
** Sol-10 Terminal Computer — Stripped-down model without 5 slot S-100 backplane; available as fully assembled or as kit form
** Sol-20 Terminal Computer — Includes 5-slot S-100 backplane; available as fully assembled or as kit form
*** Sol-20 price 1976 approximately $5000 CND with extra 16K card
* S-100 bus boards
**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 eliminates ...
— Video Display Module Board
** 3P+S — Input/Output Module 3 Parallel plus 1 Serial Board
** 4KRA — 4K Static Memory Board
** 8KRA — 8K Static Memory Board
** 16KRA — 16K DRAM memory board
** 32KRA-1 — 32K DRAM memory board
** CUTS — Tape I/O Interface Board, CUTS format and Kansas City standard
The Kansas City standard (KCS), or ''Byte'' standard, is a data storage protocol for standard cassette tapes at . It originated in a symposium sponsored by Byte (magazine), ''Byte'' magazine in November 1975 in Kansas City, Missouri to develop a ...
format
** 2KRO — EPROM memory board
** Helios II Disk Memory System
**GPM — General Purpose Memory, ROM board held CUTER Monitor Program
* Software
** SOLOS — Operating System
** CUTER — Monitor program and cassette tape loader.
** ASSM — 8080 Assembler
** BASIC/5 — 5K BASIC programming language
** Extended Cassette Basic (8K) — BASIC Interpreter
** FOCAL programming language
** ALS-8
** PTDOS
PTDOS or Processor Technology Disk Operating System is an operating system created in the late 1970s for computers using the Intel 8080 microprocessor and the Processor Technology Helios II Disk Memory System.
Commands
The following list of co ...
— operating system for use with the Helios II Disk Drive
** EDIT — 8080 Editor
** 8080 Chess — Chess Game
** ''TREK-80
''Trek-80'' is a text-based video game written by Steve Dompier in 1976 and sold by Processor Technology for their Sol-20 computer and suitable S-100 bus machines.
''Trek-80'' combines features of the seminal ''Star Trek'' game by Mike Mayfiel ...
'' — Star Trek Themed Game
** GamePack 1 — Collection of Games - Volume 1
** GamePack 2 — Collection of Games - Volume 2
Works cited
*
*
References
{{reflist
External links
Archive of Sol-20 information
Collection of old analog and digital computers at www.oldcomputermuseum.com
the SOL-20 at old-computers.com
Processor Technology SOL-PC – An early Sol-20 minus the 20
1975 establishments in California
1979 disestablishments in California
American companies established in 1975
American companies disestablished in 1979
Computer companies established in 1975
Computer companies disestablished in 1979
Defunct companies based in the San Francisco Bay Area
Defunct computer companies of the United States
Defunct computer hardware companies
Technology companies based in the San Francisco Bay Area