Embedded Files
Wikipedia 🌐 Altair 8800
Wikipedia 🌐 Altair 8800
1974 (April) - Intel releases the 8080
1974 (April) - Intel releases the 8080
1974 (May? ) - Roberts of MITS is planning to make a kit using the new 8080 - price negotiations start...
1974 (May? ) - Roberts of MITS is planning to make a kit using the new 8080 - price negotiations start...
See (https://en.wikipedia.org/wiki/Ed_Roberts_(computer_engineer) )
Roberts decided to return to the kit market with a low cost computer. The target customer would think that "some assembly required" was a desirable feature. In April 1974, Intel released the 8080 microprocessor that Roberts felt was powerful enough for his computer kit, but each 8080 chip sold for $360 in small quantities.[23] Roberts felt that the price of a computer kit had to be under $400; to meet this price, he agreed to order 1,000 microprocessors from Intel for $75 each.[24] The company was down to 20 employees and a bank loan for $65,000 financed the design and initial production of the new computer. Roberts told the bank that he expected to sell 800 computers, but he guessed that it would be around 200.
1974 (May - October) - Amazing story about the Altair Bus that was conceived, designed, tested, and prototyped - All in a very short timespan
1974 (May - October) - Amazing story about the Altair Bus that was conceived, designed, tested, and prototyped - All in a very short timespan
During the design of the Altair, the hardware required to make a usable machine was not available in time for the January 1975 launch date. The designer, Ed Roberts, also had the problem of the backplane taking up too much room. Attempting to avoid these problems, he placed the existing components in a case with additional "slots", so that the missing components could be plugged in later when they became available. The backplane is split into four separate cards, with the CPU on a fifth. He then looked for an inexpensive source of connectors, and he came across a supply of military surplus 100-pin edge connectors. The 100-pin bus was created by an anonymous draftsman, who selected the connector from a parts catalog and arbitrarily assigned signal names to groups of connector pins.[2]
1971 ARTICLE ON MITS
https://www.newspapers.com/image/156647143/?terms=%22MITS%2BINC%22
JAN 19 1975
https://www.newspapers.com/image/156367566/?terms=%22MITS%2BINC%22
micral 1973
https://www.arabianbusiness.com/photos/in-pictures-french-micral-n-first-commercial-non-kit-computer-based-on-microprocessor-674215.html
DEC 15 1976
https://www.newspapers.com/image/157625015/?terms=%22MITS%2BINC%22
Aug 14 2020 capture - [HK002G][GDrive]
S-100 bus
S-100 bus
For other uses, see S-100 (disambiguation).
S-100 bus
Year created
1974; 46 years ago
Created by
Width in bits
8
The S-100 bus or Altair bus, IEEE696-1983 (withdrawn), is an early computer bus designed in 1974 as a part of the Altair 8800. The S-100 bus was the first industry standard expansion bus for the microcomputer industry. S-100 computers, consisting of processor and peripheral cards, were produced by a number of manufacturers. The S-100 bus formed the basis for homebrew computers whose builders (e.g., the Homebrew Computer Club) implemented drivers for CP/M and MP/M. These S-100 microcomputers ran the gamut from hobbyist toy to small business workstation and were common in early home computers until the advent of the IBM PC (which some of them outperformed).
Contents
Contents
Architecture[edit]
Architecture[edit]
Harry Garland and Roger Melen, co-founders of Cromemco, holding S-100 backplane (1981)
The S-100 bus is a passive backplane of 100-pin printed circuit board edge connectors wired in parallel. Circuit cards measuring 5 × 10-inches serving the functions of CPU, memory, or I/O interface plugged into these connectors. The bus signal definitions closely follow those of an 8080 microprocessor system, since the Intel 8080 microprocessor was the first microprocessor hosted on the S-100 bus. The 100 lines of the S-100 bus can be grouped into four types: 1) Power, 2) Data, 3) Address, and 4) Clock and control.[1]
Power supplied on the bus is bulk unregulated +8 Volt DC and ±16 Volt DC, designed to be regulated on the cards to +5 V (used by TTL ICs), -5 V and +12 V for Intel 8080 CPU IC, ±12 V RS-232 line driver ICs, +12 V for disk drive motors. The onboard voltage regulation is typically performed by devices of the 78xx family (for example, a 7805 device to produce +5 volts). These were linear regulators which are commonly mounted on heat sinks.
The bi-directional 8-bit data bus of the Intel 8080 is split into two unidirectional 8-bit data buses. The processor could use only one of these at a time. The Sol-20 used a variation that had only a single 8-bit bus and used the now-unused pins as signal grounds to reduce electronic noise. The direction of the bus, in or out, was signaled using the otherwise unused DBIN pin. This became universal in the S-100 market as well, making the second bus superfluous. Later, these two 8-bit busses would be combined to support a 16-bit data width for more advanced processors, using the Sol's system to signal the direction.
The address bus is 16-bits wide in the initial implementation and later extended to 24-bits wide. A bus control signal can put these lines in a tri-state condition to allow direct memory access. The Cromemco Dazzler, for example, is an early S-100 card that retrieved digital images from memory using direct memory access.
Clock and control signals are used to manage the traffic on the bus. For example, the DO Disable line will tristate the address lines during direct memory access. Unassigned lines of the original bus specification were later assigned to support more advanced processors. For example, the Zilog Z-80 processor has a non-maskable interrupt line that the Intel 8080 processor does not. One unassigned line of the S-100 bus then was reassigned to support the non-maskable interrupt request.
History[edit]
History[edit]
The Cromemco XXU processor board, introduced in 1986. At 16.7 MHz, it is the fastest CPU ever developed for the S-100 bus. It uses a Motorola 68020 processor with 68881 co-processor and 16 Kbytes of high-speed cache memory. This CPU is used in the Cromemco CS-250 computer, widely deployed by the U.S. Air Force.
During the design of the Altair, the hardware required to make a usable machine was not available in time for the January 1975 launch date. The designer, Ed Roberts, also had the problem of the backplane taking up too much room. Attempting to avoid these problems, he placed the existing components in a case with additional "slots", so that the missing components could be plugged in later when they became available. The backplane is split into four separate cards, with the CPU on a fifth. He then looked for an inexpensive source of connectors, and he came across a supply of military surplus 100-pin edge connectors. The 100-pin bus was created by an anonymous draftsman, who selected the connector from a parts catalog and arbitrarily assigned signal names to groups of connector pins.[2]
A burgeoning industry of "clone" machines followed the introduction of the Altair in 1975. Most of these used the same bus layout as the Altair, creating a new industry standard. These companies were forced to refer to the system as the "Altair bus", and wanted another name in order to avoid referring to their competitor when describing their own system. The "S-100" name, short for "Standard 100", was coined by Harry Garland and Roger Melen, co-founders of Cromemco.[3][4] While on a flight to attend the Atlantic City PC '76 microcomputer conference in August 1976, they shared the cabin with Bob Marsh and Lee Felsenstein of Processor Technology. Melen went over to them to convince them to adopt the same name. He had a beer in his hand and when the plane hit a bump, Melen spilt some the beer on Marsh. Marsh agreed to use the name, which Melen ascribes to him wanting to get Melen to leave with his beer.[5]
The term first appeared in print in a Cromemco advertisement in the November 1976 issue of Byte magazine.[6] The first symposium on the S-100 bus, moderated by Jim Warren, was held November 20, 1976 at Diablo Valley College with a panel consisting of Harry Garland, George Morrow, and Lee Felsenstein.[7] Just one year later, the S-100 Bus would be described as "the most used busing standard ever developed in the computer industry."[8]
Cromemco was the largest of the S-100 manufacturers, followed by Vector Graphic and North Star Computers.[9] Other innovators were companies such as Alpha Microsystems, IMS Associates, Inc., Godbout Electronics (later CompuPro), and Ithaca Intersystems. In May 1984, Microsystems published a comprehensive S-100 product directory listing over 500 "S-100/IEEE-696" products from over 150 companies.[10]
The S-100 bus signals were simple to create using an 8080 CPU, but increasingly less so when using other processors like the 68000. More board space was occupied by signal conversion logic. Nonetheless by 1984, eleven different processors were hosted on the S-100 bus, from the 8-bit Intel 8080 to the 16-bit Zilog Z-8000.[10] In 1986, Cromemco introduced the XXU card, designed by Ed Lupin, utilizing a 32-bit Motorola 68020 processor.[11]
IEEE-696 Standard[edit]
IEEE-696 Standard[edit]
As the S-100 bus gained momentum, there was a need to develop a formal specification of the bus to help assure compatibility of products produced by different manufacturers. There was also a need to extend the bus so that it could support processors more capable than the Intel 8080 used in the original Altair Computer. In May 1978, George Morrow and Howard Fullmer published a “Proposed Standard for the S-100 Bus” noting that 150 vendors were already supplying products for the S-100 Bus. This proposed standard documented the 8-bit data path and 16-bit address path of the bus and stated that consideration was being given to extending the data path to 16 bits and the address path to 24 bits.[12]
In July 1979 Kells Elmquist, Howard Fullmer, David Gustavson, and George Morrow published a “Standard Specification for S-100 Bus Interface Devices.”[13] In this specification the data path was extended to 16 bits and the address path was extended to 24 bits. The IEEE 696 Working Group, chaired by Mark Garetz, continued to develop the specification which was proposed as an IEEE Standard and approved by the IEEE Computer Society on June 10, 1982.[14]
The American National Standards Institute (ANSI) approved the IEEE standard on September 8, 1983. The computer bus structure developed by Ed Roberts for the Altair 8800 computer had been extended, rigorously documented, and now designated as the American National Standard IEEE Std 696-1983.[14]
Retirement[edit]
Retirement[edit]
Racks of Cromemco S-100 Systems at the Chicago Mercantile Exchange in 1984
IBM introduced the IBM Personal Computer in 1981 and followed it with increasingly capable models: the XT in 1983 and the AT in 1984. The success of these computers cut deeply into the market for S-100 bus products. In May 1984, Sol Libes (who had been a member of the IEEE-696 Working Group) wrote in Microsystems: “there is no doubt that the S-100 market can now be considered a mature industry with only moderate growth potential, compared to the IBM PC-compatible market.”[15]
As the IBM PC products captured the low-end of the market, S-100 machines moved up-scale to more powerful OEM and multiuser systems. Banks of S-100 bus computers were used, for example, to process the trades at the Chicago Mercantile Exchange; the United States Air Force deployed S-100 bus machines for their mission planning systems.[16][17] However throughout the 1980s the market for S-100 bus machines for the hobbyist, for personal use, and even for small business was on the decline.[18]
The market for S-100 bus products continued to contract through the early 1990s, as IBM-compatible computers became more capable. In 1992, the Chicago Mercantile Exchange, for example, replaced their S-100 bus computers with the IBM model PS/2.[19] By 1994 the S-100 bus industry had contracted sufficiently that the IEEE did not see a need to continue supporting the IEEE-696 standard. The IEEE-696 standard was retired on June 14, 1994.[14]
Altair 8800 Computer with 8-inch floppy disk system
Developer
Manufacturer
Release date
January 1975; 45 years ago
Introductory price
Kit price 439 US$ ($2100 in 2019)
Assembled 621 US$ ($3000 in 2019)
Intel 8080 @ 2 MHz
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU.[1] Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics[2] and was sold by mail order through advertisements there, in Radio-Electronics, and in other hobbyist magazines. [3][4] The Altair is widely recognized as the spark that ignited the microcomputer revolution[5] as the first commercially successful personal computer.[6] The computer bus designed for the Altair was to become a de facto standard in the form of the S-100 bus, and the first programming language for the machine was Microsoft's founding product, Altair BASIC.[7][8]
History[edit]
History[edit]
This "Tracking Light for Model Rockets" project appeared in the September 1969 issue of Model Rocketry and was the first kit sold by MITS.
While serving at the Air Force Weapons Laboratory at Kirtland Air Force Base, Ed Roberts and Forrest M. Mims III decided to use their electronics background to produce small kits for model rocket hobbyists. In 1969, Roberts and Mims, along with Stan Cagle and Robert Zaller, founded Micro Instrumentation and Telemetry Systems (MITS) in Roberts' garage in Albuquerque, New Mexico, and started selling radio transmitters and instruments for model rockets.
Calculators[edit]
Calculators[edit]
The model rocket kits were a modest success and MITS wanted to try a kit that would appeal to more hobbyists. The November 1970 issue of Popular Electronics featured the Opticom, a kit from MITS that would send voice over an LED light beam. As Mims and Cagle were losing interest in the kit business, Roberts bought his partners out, then began developing a calculator kit. Electronic Arrays had just announced a set of six large scale integrated (LSI) circuit chips that would make a four-function calculator.[9] The MITS 816 calculator kit used the chipset and was featured on the November 1971 cover of Popular Electronics. This calculator kit sold for $175 ($275 assembled).[10] Forrest Mims wrote the assembly manual for this kit and many others over the next several years. He often accepted a copy of the kit as payment.
The calculator was successful and was followed by several improved models. The MITS 1440 calculator was featured in the July 1973 issues of Radio-Electronics. It had a 14-digit display, memory, and square root function. The kit sold for $200 and the assembled version was $250.[11] MITS later developed a programmer unit that would connect to the 816 or 1440 calculator and allow programs of up to 256 steps.[12]
Test equipment[edit]
Test equipment[edit]
In addition to calculators, MITS made a line of test equipment kits. These included an IC tester, a waveform generator, a digital voltmeter, and several other instruments. To keep up with the demand, MITS moved into a larger building at 6328 Linn NE in Albuquerque in 1973. They installed a wave soldering machine and an assembly line at the new location. In 1972, Texas Instruments developed its own calculator chip and started selling complete calculators at less than half the price of other commercial models. MITS and many other companies were devastated by this, and Roberts struggled to reduce his quarter-million-dollar debt.
Popular Electronics[edit]
Popular Electronics[edit]
January 1975 Popular Electronics with the Altair 8800 computer. Published on November 29, 1974.[13]
In January 1972, Popular Electronics merged with another Ziff-Davis magazine, Electronics World. The change in editorial staff upset many of their authors, and they started writing for a competing magazine, Radio-Electronics. In 1972 and 1973, some of the best construction projects appeared in Radio-Electronics.
In 1974, Art Salsberg became editor of Popular Electronics. It was Salsberg's goal to reclaim the lead in electronics projects. He was impressed with Don Lancaster's TV Typewriter (Radio Electronics, September 1973) article and wanted computer projects for Popular Electronics. Don Lancaster did an ASCII keyboard for Popular Electronics in April 1974. They were evaluating a computer trainer project by Jerry Ogden when the Mark-8 8008-based computer by Jonathan Titus appeared on the July 1974 cover of Radio-Electronics. The computer trainer was put on hold and the editors looked for a real computer system. (Popular Electronics gave Jerry Ogden a column, Computer Bits, starting in June 1975.)[14]
One of the editors, Les Solomon, knew MITS was working on an Intel 8080 based computer project and thought Roberts could provide the project for the always popular January issue. The TV Typewriter and the Mark-8 computer projects were just a detailed set of plans and a set of bare printed circuit boards. The hobbyist faced the daunting task of acquiring all of the integrated circuits and other components. The editors of Popular Electronics wanted a complete kit in a professional-looking enclosure.[15]
Ed Roberts and his head engineer, Bill Yates, finished the first prototype in October 1974 and shipped it to Popular Electronics in New York via the Railway Express Agency. However, it never arrived due to a strike by the shipping company. Solomon already had a number of pictures of the machine and the article was based on them. Roberts got to work on building a replacement. The computer on the magazine cover is an empty box with just switches and LEDs on the front panel. The finished Altair computer had a completely different circuit board layout than the prototype shown in the magazine.[16] The January 1975 issues appeared on newsstands a week before Christmas of 1974 and the kit was officially (if not yet practically) available for sale.[14][15][13]
The name[edit]
The name[edit]
A kit-built Altair 8800 computer with the popular Model 33 ASR (Automatic Send and Receive) Teletype as terminal.
The typical MITS product had a generic name like the "Model 1440 Calculator" or the "Model 1600 Digital Voltmeter". Ed Roberts was busy finishing the design and left the naming of the computer to the editors of Popular Electronics.
One explanation of the Altair name, which editor Les Solomon later told the audience at the first Altair Computer Convention (March 1976), is that the name was inspired by Les's 12-year-old daughter, Lauren. "She said why don't you call it Altair – that's where the Enterprise is going tonight."[17] The Star Trek episode is probably "Amok Time", as this is the only one from The Original Series which takes the Enterprise crew to Altair (Six).
Another explanation is that the Altair was originally going to be named the PE-8 (Popular Electronics 8-bit), but Les Solomon thought this name to be rather dull, so Les, Alexander Burawa (associate editor), and John McVeigh (technical editor) decided that: "It's a stellar event, so let's name it after a star." McVeigh suggested "Altair", the twelfth brightest star in the sky.[15][18]
Intel 8080[edit]
Intel 8080[edit]
Ed Roberts had designed and manufactured programmable calculators and was familiar with the microprocessors available in 1974. He thought the Intel 4004 and Intel 8008 were not powerful enough (in fact several microcomputers based on Intel chips were already on the market: the Canadian company Microsystems International's CPS-1 built-in 1972 used a MIL MF7114 chip modeled on the 4004, the Micral marketed in January 1973 by the French company R2E and the MCM/70 marketed in 1974 by the Canadian company Micro Computer Machines); the National Semiconductor IMP-8 and IMP-16 required external hardware; the Motorola 6800 was still in development. So he chose the 8-bit Intel 8080.[19] At that time, Intel's main business was selling memory chips by the thousands to computer companies. They had no experience in selling small quantities of microprocessors. When the 8080 was introduced in April 1974, Intel set the single unit price at $360 (About $1,700 in 2014 dollars). "That figure had a nice ring to it," recalled Intel's Dave House in 1984. "Besides, it was a computer, and they usually cost thousands of dollars, so we felt it was a reasonable price."[20] Ed Roberts had experience in buying OEM quantities of calculator chips and he was able to negotiate a $75 price (about $350 in 2014 dollars) for the 8080 microprocessor chips.[21][22]
Intel made the Intellec-8 Microprocessor Development System that typically sold for a very profitable $10,000. It was functionally similar to the Altair 8800 but it was a commercial grade system with a wide selection of peripherals and development software.[23][24] Customers would ask Intel why their Intellec-8 was so expensive when that Altair was only $400. Some salesmen said that MITS was getting cosmetic rejects or otherwise inferior chips. In July 1975, Intel sent a letter to its sales force stating that the MITS Altair 8800 computer used standard Intel 8080 parts. The sales force should sell the Intellec system based on its merits and that no one should make derogatory comments about valued customers like MITS. The letter was reprinted in the August 1975 issue of MITS Computer Notes.[25] The "cosmetic defect" rumor has appeared in many accounts over the years although both MITS and Intel issued written denials in 1975.[26]
The launch[edit]
The launch[edit]
A May 1975 advertisement for the Altair 8800 Computer appeared in Popular Electronics, Radio-Electronics, and other magazines.
For a decade, colleges had required science and engineering majors to take a course in computer programming, typically using the FORTRAN or BASIC languages.[27][28] This meant there was a sizable customer base who knew about computers. In 1970, electronic calculators were not seen outside of a laboratory, but by 1974 they were a common household item. Calculators and video games like Pong introduced computer power to the general public. Electronics hobbyists were moving on to digital projects such as digital voltmeters and frequency counters. The Altair had enough power to be actually useful, and was designed as an expandable system that opened it up to all sorts of applications.
Ed Roberts optimistically told his banker that he could sell 800 computers, while in reality they needed to sell 200 over the next year just to break even. When readers got the January issue of Popular Electronics, MITS was flooded with inquiries and orders. They had to hire extra people just to answer the phones. In February MITS received 1,000 orders for the Altair 8800. The quoted delivery time was 60 days but it was months before they could meet that. Roberts focused on delivering the computer; all of the options would wait until they could keep pace with the orders. MITS claimed to have delivered 2,500 Altair 8800s by the end of May.[29] The number was over 5,000 by August 1975.[30] MITS had under 20 employees in January but had grown to 90 by October 1975.[31]
The Altair 8800 computer was a break-even sale for MITS. They needed to sell additional memory boards, I/O boards and other options to make a profit. The system came with a "1024 word" (1024 byte) memory board populated with 256 bytes. The BASIC language was announced in July 1975 and it required one or two 4096 word memory boards and an interface board.
MITS Price List, Popular Electronics, August 1975.[32]
DescriptionKit PriceAssembled
4K BASIC language (when purchased with Altair, 4096 words of memory and interface board) $60
8K BASIC language (when purchased with Altair, two 4096-word memory boards and interface board) $75
MITS had no competition in the US for the first half of 1975. Their 4K memory board used dynamic RAM and it had several design problems.[31] The delay in shipping optional boards and the problems with the 4K memory board created an opportunity for outside suppliers.
An enterprising Altair owner, Robert Marsh, designed a 4K static memory that was plug-in compatible with the Altair 8800 and sold for $255.[33] His company was Processor Technology, one of the most successful Altair compatible board suppliers. Their advertisement in the July 1975 issue of Popular Electronics promised interface and PROM boards in addition to the 4K memory board. They would later develop a popular video display board that would plug directly into the Altair.
A consulting company in San Leandro, California, IMS Associates Inc., wanted to purchase several Altair computers but the long delivery time convinced them that they should build their own computers. In the October 1975 Popular Electronics, a small advertisement announced the IMSAI 8080 computer. The ad noted that all boards were "plug compatible" with the Altair 8800. The computer cost $439 for a kit. The first 50 IMSAI computers shipped in December 1975.[34] The IMSAI 8080 computer improved on the original Altair design in several areas. It was easier to assemble: The Altair required 60 wire connections between the front panel and the mother board (backplane.) The IMSAI motherboard had 18 slots. The MITS motherboard consisted of 4 slots segments that had to be connected together with 100 wires. The IMSAI also had a larger power supply to handle the increasing number of expansion boards used in typical systems. The IMSAI advantage was short lived because MITS had recognized these shortcomings and developed the Altair 8800B which was introduced in June 1976.
In 1977, Pertec Computer Corporation purchased MITS and began to market the computer, without changes (except for branding), as the PCC 8800 in 1978.[35]
Description[edit]
Description[edit]
Altair 8800 front panel (1st model)
Altair 8800b front panel (2nd model)
Inside the Altair 8800b (2nd model)
In the first design of the Altair, the parts needed to make a complete machine would not fit on a single motherboard, and the machine consisted of four boards stacked on top of each other with stand-offs. Another problem facing Roberts was that the parts needed to make a truly useful computer weren't available, or wouldn't be designed in time for the January launch date. So during the construction of the second model, he decided to build most of the machine on removable cards, reducing the motherboard to nothing more than an interconnect between the cards, a backplane. The basic machine consisted of five cards, including the CPU on one and memory on another. He then looked for a cheap source of connectors, and came across a supply of 100-pin edge connectors. The S-100 bus was eventually acknowledged by the professional computer community and adopted as the IEEE-696 computer bus standard.
The Altair bus consists of the pins of the Intel 8080 run out onto the backplane. No particular level of thought went into the design, which led to such disasters as shorting from various power lines of differing voltages being located next to each other.[citation needed] Another oddity was that the system included two unidirectional 8-bit data buses, when the normal practice was for a single bidirectional bus (this oddity did, however, allow a later expansion of the S-100 standard to 16 bits bidirectional by using both 8-bit buses in parallel). A deal on power supplies led to the use of +8V and +18V,[citation needed] which had to be locally regulated on the cards to TTL (+5V) or RS-232 (+12V) standard voltage levels.
The Altair shipped in a two-piece case. The backplane and power supply were mounted on a base plate, along with the front and rear of the box. The "lid" was shaped like a C, forming the top, left, and right sides of the box. The front panel, which was inspired by the Data General Nova minicomputer, included a large number of toggle switches to feed binary data directly into the memory of the machine, and a number of red LEDs to read those values back out.[36]
Programming the Altair via the front panel could be a tedious and time-consuming process. Programming required the toggling of the switches to positions corresponding to the desired 8080 microprocessor instruction or opcode in binary, then used the 'DEPOSIT NEXT' switch to load that instruction into the next address of the machine's memory. This step was repeated until all the opcodes of a presumably complete and correct program were in place. The only output from the programs was the patterns of lights on the panel. Nevertheless, many were sold in this form. Development was already underway on additional cards, including a paper tape reader for storage, additional RAM cards, and an RS-232 interface to connect to a proper Teletype terminal.
Software[edit]
Software[edit]
Altair BASIC[edit]
Altair BASIC[edit]
Main article: Altair BASIC
Ed Roberts received a letter from Traf-O-Data asking if he would be interested in buying its BASIC programming language for the machine. He called the company and reached a private home, where no one had heard of anything like BASIC. In fact the letter had been sent by Bill Gates and Paul Allen from the Boston area, and they had no BASIC yet to offer. When they called Roberts to follow up on the letter he expressed his interest, and the two started work on their BASIC interpreter using a self-made simulator for the 8080 on a PDP-10 minicomputer. They figured they had 30 days before someone else beat them to the punch, and once they had a version working on the simulator, Allen flew to Albuquerque to deliver the program, Altair BASIC (aka MITS 4K BASIC), on a paper tape. The first time it was run, it displayed "READY"[37] then Allen typed "PRINT 2+2" and it immediately printed the correct answer: "4". The game Lunar Lander was entered in and this worked as well. Gates soon joined Allen and formed Microsoft, then spelled "Micro-Soft".
Altair DOS[edit]
Altair DOS[edit]
Announced in late 1975, it started shipping in August 1977.
VIDEOS
VIDEOS
(Jan 22, 2020) - Bob Spencer of MITS Part 2: Intel CPUs, PC Magazine and more!
(Jan 22, 2020) - Bob Spencer of MITS Part 2: Intel CPUs, PC Magazine and more!
Saved video : [HV00CB][GDrive]
"This is part 2 of our 8-Bit Boyz interview with Bob Spencer who was one of the original engineers at MITS in Albuquerque, NM that worked on the Altair 8800 computer. I was able to sit down with Bob and have him share his memories of his days back at MITS along with the folks that help start the computer revolution such as Bill Gates, Paul Allen, David Bunnell, Ed Roberts, Eddie Currie and more. Special thanks to Bob Spencer for all his memories and stories from a time that was historic and started the computer revolution which has lead us to the devices we use daily today! "
Aug 14 2020 saved wikipedia - [HK002F][GDrive]
Ed Roberts (computer engineer)
Ed Roberts (computer engineer)
From Wikipedia, the free encyclopedia
Jump to navigationJump to search
Ed Roberts
Ed Roberts in 2002
Born
Henry Edward Roberts
September 13, 1941
Died
April 1, 2010 (aged 68)
Cochran, Georgia, United States
Nationality
American
Education
Occupation
Electrical engineer
Businessman
Entrepreneur
Farmer
Medical doctor
Known for
Spouse(s)
Joan Clark
(
m. 1962–1988)
Donna Mauldin
(
m. 1991–1999)
Rosa Cooper
(
m. 2000–2010)
Children
6
Henry Edward "Ed" Roberts (September 13, 1941 – April 1, 2010) was an American engineer, entrepreneur and medical doctor who invented the first commercially successful personal computer in 1974.[1] He is most often known as "the father of the personal computer."[2] He founded Micro Instrumentation and Telemetry Systems (MITS) in 1970 to sell electronics kits to model rocketry hobbyists, but the first successful product was an electronic calculator kit that was featured on the cover of the November 1971 issue of Popular Electronics.[3] The calculators were very successful and sales topped one million dollars in 1973.[4] A brutal calculator price war left the company deeply in debt by 1974. Roberts then developed the Altair 8800 personal computer that used the new Intel 8080 microprocessor. This was featured on the cover of the January 1975 issue of Popular Electronics, and hobbyists flooded MITS with orders for this $397 computer kit.
Bill Gates and Paul Allen joined MITS to develop software and Altair BASIC was Microsoft's first product. Roberts sold MITS in 1977 and retired to Georgia where he farmed, studied medicine and eventually became a small-town doctor living in Cochran, Georgia.
Contents
Contents
Early life[edit]
Early life[edit]
Roberts was born on September 13, 1941 in Miami, Florida to Henry Melvin Roberts, an appliance repairman, and Edna Wilcher Roberts, a homemaker. His younger sister Cheryl was born in 1947. During World War II, while his father was in the Army, Roberts and his mother lived on the Wilcher family farm in Wheeler County, Georgia. After the war, the family returned to Miami, but Roberts would spend his summers with his grandparents in rural Georgia. Roberts' father had an appliance repair business in Miami.[5][6]
Roberts became interested in electronics and built a small relay-based computer while in high school. Medicine was his true passion, however, and he entered University of Miami with the intention of becoming a doctor, the first in his family to attend college. There he met a neurosurgeon who shared his interest in electronics. The doctor suggested that Roberts get an engineering degree before applying to medical school, and Roberts changed his major to electrical engineering.[6][7]
Roberts married Joan Clark while at the university, and when she became pregnant Roberts knew that he would have to drop out of school to support his new family. The U.S. Air Force had a program that would pay for college, and in May 1962 he enlisted with the hope of finishing his degree through the Airman Education & Commissioning Program.[6][8]
After basic training, Roberts attended the Cryptographic Equipment Maintenance School at Lackland Air Force Base in San Antonio, Texas. Because of his electrical engineering studies at college, Roberts was made an instructor at the Cryptographic School when he finished the course. To augment his meager enlisted man's pay, Roberts worked on several off-duty projects and even set up a one-man company, Reliance Engineering. The most notable job was to create the electronics that animated the Christmas characters in the window display of Joske's department store in San Antonio. In 1965, he was selected for an Air Force program to complete his college degree and become a commissioned officer. Roberts earned an electrical engineering degree from Oklahoma State University in 1968 and was assigned to the Laser Division of the Weapons Laboratory at Kirtland AFB in Albuquerque, New Mexico.[6][9] In 1968, he looked into applying to medical school but learned that, at age 27, he was considered too old.[6]
Micro Instrumentation and Telemetry Systems[edit]
Micro Instrumentation and Telemetry Systems[edit]
Main article: Micro Instrumentation and Telemetry Systems
March 1970 advertisement, when MITS was located in Ed Roberts' garage.
Roberts worked with Forrest Mims at the Weapons Laboratory, and both shared an interest in model rocketry. Mims was an advisor to the Albuquerque Model Rocket Club and met the publisher of Model Rocketry magazine at a rocketry conference. This led to an article in the September 1969 issue of Model Rocketry, "Transistorized Tracking Light for Night Launched Model Rockets".[10] Roberts, Mims, and lab coworkers Stan Cagle and Bob Zaller decided that they could design and sell electronics kits to model rocket hobbyists.[11] Roberts wanted to call the new company Reliance Engineering, but Mims wanted to form an acronym similar to the Massachusetts Institute of Technology's MIT. Cagle came up with Micro Instrumentation and Telemetry Systems (MITS).[12] They advertised the light flasher, a roll rate sensor with transmitter, and other kits in Model Rocketry, but the sales were disappointing.
Mims wrote an article about the new technology of light-emitting diodes that was to be published in the November 1970 issue of Popular Electronics magazine. He asked the editors if they also wanted a project story, and they agreed. Roberts and Mims developed an LED communicator that would transmit voice on an infrared beam of light to a receiver hundreds of feet away. Readers could buy a kit of parts to build the Opticom LED Communicator from MITS for $15.[13] MITS sold just over a hundred kits. Mims was now out of the Air Force and wanted to pursue a career as a technology writer. Roberts bought out his original partners and focused the company on the emerging market of electronic calculators.[14]
Calculators[edit]
Calculators[edit]
June 1972 advertisement for MITS Model 1440 Calculator
Roberts's first real experience with computers came while at Oklahoma State University where engineering students had free access to an IBM 1620 computer.[15] His office at the Weapons Laboratory had the state of the art Hewlett-Packard 9100A programmable calculator in 1968. Roberts had always wanted to build a digital computer and, in July 1970, Electronic Arrays announced a set of six LSI integrated circuits that would make a four-function calculator.[16][17] Roberts was determined to design a calculator kit and got fellow Weapons Laboratory officers William Yates and Ed Laughlin to invest in the project with time and money.[18]
The first product was a "four-function" calculator that could add, subtract, multiply, and divide. The display was only eight digits, but the calculations were performed with 16 digits precision. The MITS Model 816 calculator kit was featured on the November 1971 cover of Popular Electronics.[3] The kit sold for $179 and an assembled unit was $275. Unlike the previous kits that MITS had offered, thousands of calculator orders came in each month.[19]
The monthly sales reached $100,000 in March 1973, and MITS moved to a larger building with 10,000 square feet (930 square meters) of space.[4] In 1973, MITS was selling every calculator that they could make, and 110 employees worked in two shifts assembling them.[20] The functionality of calculator integrated circuits increased at a rapid pace and Roberts was designing and producing new models. The popularity of electronic calculators drew the traditional office equipment companies and the semiconductor companies into the market. In September 1972, Texas Instruments (TI) introduced the TI-2500 portable four-function calculator that sold for $120.[21] The larger companies could sell below cost to win market share. By early 1974, Ed Roberts found that he could purchase a calculator in a retail store for less than his cost of materials. MITS was now $300,000 in debt, and Roberts was looking for a new hit product.[22]
Altair 8800 computer[edit]
Altair 8800 computer[edit]
Main article: Altair 8800
May 1975 advertisement for the Altair 8800 computer kit
Roberts decided to return to the kit market with a low cost computer. The target customer would think that "some assembly required" was a desirable feature. In April 1974, Intel released the 8080 microprocessor that Roberts felt was powerful enough for his computer kit, but each 8080 chip sold for $360 in small quantities.[23] Roberts felt that the price of a computer kit had to be under $400; to meet this price, he agreed to order 1,000 microprocessors from Intel for $75 each.[24] The company was down to 20 employees and a bank loan for $65,000 financed the design and initial production of the new computer. Roberts told the bank that he expected to sell 800 computers, but he guessed that it would be around 200.[25]
Art Salsberg, editorial director of Popular Electronics, was looking for a computer construction project, and his technical editor Les Solomon knew that MITS was working on an Intel 8080-based computer kit. Roberts assured Solomon that the project would be complete by November to meet the press deadline for the January 1975 issue. The first prototype was finished in October and shipped to Popular Electronics in New York for the cover photograph, but it was lost in transit. Solomon already had a number of pictures of the machine, and the article was based on them. Roberts and Yates got to work on building a replacement. The computer on the magazine cover was an empty box with just switches and LEDs on the front panel. The finished Altair computer had a completely different circuit board layout than the prototype shown in the magazine.[26]
Altair 8800 Computer with 8-inch floppy disk system
MITS products typically had generic names such as the Model 1440 Calculator or the Model 1600 Digital Voltmeter. The editors of Popular Electronics wanted a more alluring name for the computer. MITS technical writer David Bunnell came up with three pages of possible names, but Roberts was too busy finishing the computer design to choose one. There are several versions of the story of who selected Altair as the computer name. At the first Altair Computer Convention (March 1976), Les Solomon told the audience that the name was inspired by his 12-year-old daughter Lauren. "She said why don't you call it Altair – that's where the [Star Trek] Enterprise is going tonight."[6][27] The December 1976 issue of Popular Science misquoted this account, giving credit to Ed Roberts' daughter.[28] His only daughter Dawn was not born until 1983.[1] Both of these versions have appeared in many books, magazines, and web sites.
Editor Alexander Burawa recalls a less dramatic version. The Altair was originally going to be named the PE-8 (Popular Electronics 8-bit), but Les Solomon thought this name to be rather dull, so Solomon, Burawa, and John McVeigh decided that: "It's a stellar event, so let's name it after a star." McVeigh suggested "Altair", the twelfth-brightest star in the sky.[29][30]
When the January 1975 issue of Popular Electronics reached readers in mid-December 1974, MITS was flooded with orders.[31] They had to hire extra people just to answer the phones. In February, MITS received 1,000 orders for the Altair 8800. The quoted delivery time was 60 days, but it was many more months before the machines were shipped. By August 1975, they had shipped over 5,000 computers.[32]
The Altair 8800 computer was a break-even sale for MITS. They needed to sell additional memory boards, I/O boards, and other options to make a profit. The April 1975 issue of the MITS newsletter Computer Notes had a page-long price list that offered over 15 optional boards.[33] The delivery time given was 60 or 90 days, but many items were never produced and dropped from future price lists. Initially, Roberts decided to concentrate on production of the computers. Prompt delivery of optional boards did not occur until October 1975.
There were several design and component problems in the MITS 4K Dynamic RAM board. By July, new companies such as Processor Technology were selling 4K Static RAM boards with the promise of reliable operation.[34] Ed Roberts acknowledged the 4K Dynamic RAM board problems in the October 1975 Computer Notes. The price was reduced from $264 to $195 and existing purchasers got a $50 refund. MITS released its own 4K Static RAM board in January 1976.
Several other companies started making add-in boards and the first clone, the IMSAI 8080, was available in December 1975.[35]
Altair BASIC[edit]
Altair BASIC[edit]
Main article: Altair BASIC
Bill Gates was a student at Harvard University and Paul Allen worked for Honeywell in Boston when they saw the Altair computer on the cover of Popular Electronics. They had previously written software for the earlier Intel 8008 microprocessor and knew the Intel 8080 was powerful enough to support a BASIC interpreter. They sent a letter to MITS claiming to have a BASIC interpreter for the 8080 microprocessor. Roberts was interested, so Gates and Allen began work on the software. Both had experience with the Digital Equipment Corporation PDP-10 minicomputers that they would use. Allen modified the DEC Macro Assembler to produce code for the Intel 8080 and wrote a program to emulate the 8080 so they could test their BASIC without having an Altair computer. Using DEC's BASIC-PLUS language as a guide, Gates determined what features would work with the limited resources of the Altair computer. Gates then started writing the 8080 assembly-language code on yellow legal pads. In February Gates and Allen started using a PDP-10 at Harvard to write and debug BASIC. They also enlisted another Harvard student, Monte Davidoff, to write the floating-point math routines.[36]
Altair 8K BASIC on paper tape. Bill Gates gave Paul Allen a paper tape containing BASIC to take to MITS.
Paul Allen flew to Albuquerque, New Mexico, in March 1975 to test BASIC on a real Altair 8800 computer. Roberts picked him up at the airport in his pickup truck and drove to the nondescript storefront where MITS was located. Allen was not impressed. The Altair computer with 7 kB of memory that BASIC required was still being tested and would not be ready until the next day. Roberts had booked Allen in the most expensive hotel in Albuquerque and the room was $40 more than Allen brought with him. Roberts paid for the room and wondered who is this software guy who can not afford a room in a hotel.[37]
The next day the Altair with 7 kB had finally passed its memory test and Allen had their BASIC interpreter on a paper tape Bill Gates had created just before Allen left Boston. It took almost 15 minutes for the Teletype to load the program into the Altair then the Teletype printed "MEMORY SIZE?" Allen entered 7168 and the Teletype printed "READY". Both Allen and Roberts were stunned their software and hardware actually worked. They entered several small programs and they worked. The BASIC interpreter was not complete and crashed several times, but Roberts had a high level language for his computer. Roberts hired Allen as Vice President and Director of Software at MITS.[38][39] Bill Gates also worked at MITS; the October 1975 company newsletter gives his title as "Software Specialist".[40]
Bill Gates remained at Harvard, but continued working on BASIC. Students were allowed to use the DEC PDP-10, but officials were not pleased when they found that Gates was developing a commercial product. The school then implemented a policy that forced Gates to use a commercial time share service to work on BASIC.[41]
On July 22, 1975, MITS signed a contract for the Altair BASIC with Bill Gates and Paul Allen. They received $3,000 at signing and a royalty for each copy of BASIC sold, with a cap of $180,000. MITS received an exclusive worldwide license to the program for 10 years. They also had exclusive rights to sublicense the program to other companies and agreed to use its "best efforts" to license, promote and commercialize the program. MITS would supply the computer time necessary for development on a PDP-10 owned by the Albuquerque school district.[42]
MITS realized that BASIC was a competitive advantage and bundled the software with computer hardware sales. Customers who purchased the computer, memory, and I/O boards from MITS could get BASIC for $75; the standalone price was $500. Many hobbyists purchased their hardware from a third-party and "borrowed" a copy of Altair BASIC. Roberts refused to sub-license BASIC to other companies; this led to arbitration in 1977 between MITS and the new "Micro-Soft". The arbitrator agreed with Microsoft and allowed them to license the 8080 BASIC to other companies. Roberts was disappointed with this ruling. Since both Allen and Gates had been employees of MITS and he paid for the computer time, Roberts felt it was his software.[43]
Sale to Pertec[edit]
Sale to Pertec[edit]
In 1976, MITS had 230 employees and sales of $6 million.[44] Roberts was tiring of his management responsibilities and was looking for a larger partner. MITS had always used Pertec Computer Corporation disk drives[45] and on December 3, 1976, Pertec signed a letter of intent to acquire MITS for $6 million in stock.[46] The deal was completed in May 1977 and Roberts' share was $2–3 million.[6][47] The Altair products were merged into the Pertec line, and the MITS facility was used to produce the PCC-2000 small-business computer. The Albuquerque plant was closed in December 1980 and the production was moved to the Pertec plants in Irvine, California.[48]
Medical doctor[edit]
Medical doctor[edit]
In late 1977 Roberts returned to rural Georgia and bought a large farm in Wheeler County where he had often visited his grandparents' home in his youth.[6][49] He had a non-compete agreement with Pertec covering hardware products, so he became a gentleman farmer and started a software company. His age could have thwarted his dream of becoming a medical doctor, but nearby Mercer University started a medical school in 1982. Roberts was in the first class and graduated with an M.D. in 1986. He did his residency in internal medicine and in 1988 established a practice in the small town of Cochran, Georgia.[6][50][51] In 2009, Dr. Roberts was elected to Alpha Omega Alpha, the medical honor society. He was nominated by Mercer alumnus Guy Foulkes, MD based on Roberts’ dual accomplishment of developer of the first personal computer and his devotion to rural medicine.
Personal life[edit]
Personal life[edit]
Roberts married Joan Clark (b. 1941) in 1962 and they had five sons, Melvin (b. 1963), Clark (b. 1964), John David (b. 1965), Edward (b. 1970), Martin (b. 1975) and a daughter Dawn (b. 1983). They were divorced in 1988.[1][6][52]
Roberts married Donna Mauldin in 1991 and they were still married when interviewed by The Atlanta Journal-Constitution in April 1997.[1] He was married to Rosa Cooper from 2000 until his death.[53]
Roberts died April 1, 2010 after a months-long bout with pneumonia, at the age of 68.[54][55] His sister, Cheryl R Roberts (b. November 13, 1947 – d. March 6, 2010), of nearby Dublin, Georgia died at age 62, a few weeks before his death.[56] During his last hospitalization in Macon, Georgia, hospital staffers were stunned to see an unannounced Bill Gates, who had come to pay last respects to his first employer. He was survived by his wife, all six of his children and his mother, Edna Wilcher Roberts. All live in Georgia.[57]
Works[edit]
Works[edit]
Books
Roberts, H. Edward; Forrest Mims (1974). Electronic Calculators. Indianapolis: Howard W Sams. ISBN 978-0-672-21039-6.
Magazines
Mims, Forrest M.; Henry E. Roberts (November 1970). "Assemble an LED Communicator – The Opticom". Popular Electronics. Vol. 33 no. 5. Ziff Davis. pp. 45–50, 98–99.
Roberts, Ed (November 1971). "Electronic desk calculator you can build". Popular Electronics. Vol. 35 no. 5. Ziff Davis. pp. 27–32.
Roberts, H. Edward (November 1973). "Understanding computer arithmetic". Radio-Electronics. Vol. 44 no. 22. Gernsback. pp. 55–60. ISSN 0033-7862.
Roberts, H. Edward; William Yates (January 1975). "Altair 8800 Minicomputer, Part 1". Popular Electronics. Vol. 7 no. 1. Ziff Davis. pp. 33–38. ISSN 0032-4485. Part 2 in the February 1975 issue.
Roberts, H. Edward; Paul Van Baalen (November 1975). "First Motorola/AMI "6800" MPU computer project". Popular Electronics. Vol. 8 no. 5. Ziff Davis. pp. 33–36. ISSN 0032-4485. Part 2 in the December 1975 issue.
When Popular Electronics ran its first cover story on the Altair in January 1975, 1 was the technical director for the magazine and therefore fortunate enough to witness and aid in the birth of the personal/ home computer. Before those early years become set in stone, I would like to offer this reminiscence and give credit to those pioneers whose names may be unknown to the home computer users now benefiting from the fruits of their labors.
It all started for me in the summer of 1972, during a vacation trip out west. My wife and I were near Albuquerque when I called Forrest Mims, a contributor to the magazine who lived in this town out in the middle of nowhere. His father had a small company called M. I. T. S. (Micro Instrumentation and Telemetry Systems), which occupied the bathroom of Forrest's mobile home and manufactured small electronic gadgets for radio-control airplanes and model rockets.
The Mims invited us out to see them, and during the conversation Forrest mentioned that he had a friend who was as crazy about electronics as I was. He insisted that I meet this fellow, Ed Roberts, so later that night we got together in a steak bar in downtown Albuquerque. Just out of the military, Ed had this idea about offering an electronic calculator kit. And I had to listen, since he stands over six feet and weighs 235 pounds or so.
Anyway, I decided to write about the kit in the pages of Popular Electronics. After the article appeared, many kits were sold and Ed bought out M.I.T.S., moved it into a real building and dropped the periods to make it MITS. Pretty soon, everybody and his uncle got into calculators and they were a dime a dozen. Ed was giving serious thought to folding his company when we heard some electronic stirrings that sounded really wild. One of our competitors, Radio-Electronics, was preparing a story on a "computer" using an Intel 8008 microprocessor chip. Ed looked into it, obtained an even newer Intel chip called the 8080, and with a couple of engineering friends set about creating his own computer.
The MITS computer was ready that summer. Ed said it could be sold as a kit for about $400, which was fantastic since I knew the Radio-Electronics Mark-8 computer was having difficulties (no peripherals, no language, etc. ). One day he phoned to say his first computer was being shipped to me by Railway Express Agency. A week later, no computer had arrived. I complained to the people at REA, who retorted: "Our computer has never lost anything!" During the fourth week they went bankrupt, having lost not only the first MITS computer but their entire shipping empire as well.
Luckily, Ed had sent me another computer by a different route. There I was, in a small office in New York with a metal box marked PE-8 on my desk, and an ASR-33 Teletype as the only way of inputting or displaying instructions and data. Between the frontpanel switch start-up routine and the noisy Teletype, I was told to take "that thing" home, which I suppose made the PE-8 the first workable home computer.
Art Salsberg, my boss, said he would go along with me on publishing a construction article on a microcomputer ("Heaven only knows who will build one!"), so the next step was finding a catchy name for our 8-bitter. After dinner one night I asked my twelveyear-old daughter, who was watching Star Trek, what the computer on the Enterprise was called.
"Computer," she answered.
That's a nice name, I thought, but not sexy. Then she said:
"Why don't you call it Altair? That's where the Enterprise is going in this episode."
[HW0051][GDrive]
My introduction to the Mark-8 came one bright spring morning in 1973, when a forceful young man by the name of Jonathan Titus called to tell me about his working model of a microcomputer built around the new Intel 8008. (A bargain-priced 8008 microprocessor cost $125 at the time.) Deciding that a personal visit was necessary, I flew down to Blacksburg, Virginia, where Jon took me to a spare room in his college apartment and showed me the first micro system: a little green box decorated with a bunch of toggle switches and flickering red lights.
What, I wondered, would anyone do with a computer that needed to be programmed ... one step at a time ... by setting eight toggle switches to represent each instruction?
Despite my misgivings and after months of preparation, we published our article on the Mark-8 computer. There was no way we could squeeze it into a single issue, and for the second time in our history we offered a booklet of complete construction information. The booklet sold by the thousands: each new stack that came in from the printer was gone in no time, and we'd have to order more. To this day I don't know how many people spent how many hours entering instructions and data into the Mark-8 ...
I am often asked whether I anticipated the current personal computer revolution when I was introduced to Jon Titus' original micro system. My answer is yes, but I still don't think the computer is the ideal tool for everyone. In business and education there is no doubt that its growth as a tool and as a time- and dollar-saver will continue. When it comes to computers in the home, however, I have my doubts.
I am not convinced that the average person has enough need for a computer to justify its cost. Yes, it's a great game machine. Yes, it's a great educational device. Yes, it's a great typewriter. But unless you're going to do your banking, control your home appliances, keep your holiday mailing lists, calculate your income taxes and your budget, it's difficult for me to see a personal computer in every household. Until the price of hardware comes down, and until software exists at low cost to do the kinds of things the average American needs done around the home, the computer revolution will remain largely a business revolution.
LARRY STECKLER, publisher of Radio-Electronics
THE FIRST DO-IT YOURSELF PERSONAL COMPUTER
Titled simply "Computer," with the subhead "Build the Mark-8, Your Personal Minicomputer," RadioElectronic's cover story for July 1974 introduced the first homemade machine to use a microprocessor.My introduction to the Mark-8 came one bright spring morning in 1973, when a forceful young man by the name of Jonathan Titus called to tell me about his working model of a microcomputer built around the new Intel 8008. (A bargain-priced 8008 microprocessor cost $125 at the time.) Deciding that a personal visit was necessary, I flew down to Blacksburg, Virginia, where Jon took me to a spare room in his college apartment and showed me the first micro system: a little green box decorated with a bunch of toggle switches and flickering red lights.
What, I wondered, would anyone do with a computer that needed to be programmed ... one step at a time ... by setting eight toggle switches to represent each instruction?
Despite my misgivings and after months of preparation, we published our article on the Mark-8 computer. There was no way we could squeeze it into a single issue, and for the second time in our history we offered a booklet of complete construction information. The booklet sold by the thousands: each new stack that came in from the printer was gone in no time, and we'd have to order more. To this day I don't know how many people spent how many hours entering instructions and data into the Mark-8 ...
I am often asked whether I anticipated the current personal computer revolution when I was introduced to Jon Titus' original micro system. My answer is yes, but I still don't think the computer is the ideal tool for everyone. In business and education there is no doubt that its growth as a tool and as a time- and dollar-saver will continue. When it comes to computers in the home, however, I have my doubts.
I am not convinced that the average person has enough need for a computer to justify its cost. Yes, it's a great game machine. Yes, it's a great educational device. Yes, it's a great typewriter. But unless you're going to do your banking, control your home appliances, keep your holiday mailing lists, calculate your income taxes and your budget, it's difficult for me to see a personal computer in every household. Until the price of hardware comes down, and until software exists at low cost to do the kinds of things the average American needs done around the home, the computer revolution will remain largely a business revolution.
LARRY STECKLER, publisher of Radio-Electronics
The next day I called Ed to try out the new name. His answer was curt: "I don't care what you call it, if we don't sell two hundred we're doomed!" So Altair it became.
About a month before we ran the Altair story I had a visit from another imposingly large person, Roger Melen of Stanford University, who had written several articles for us. Roger contemplated the Altair set up on the table, and when I told him it was a computer his eyes glazed over. He muttered something about getting one for himself and his friend Harry Garland, who also wrote for us, and asked me for the name and address of the kit supplier. Then he vanished. Later I heard he took the next plane to Albuquerque, marched into Ed's office and bought Altair #2 right off his desk.
A few months later I got a call from Roger, asking me to fly out to San Francisco to see something very important. When I got there, he took me to the apartment he shared with Harry and showed me what he'd done with his Altair. Plugged into the machine was a double set of add-on circuit boards called the Dazzler, whose video output could create an amazing display on a color TV-the first plug-in expansion board for a personal computer. The software was called Kaleidoscope, a program that is relatively common today, but in 1976 ... ! Because of its ever-changing color display, Kaleidoscope would actually become a traffic stopper: Stan Veit ran the program all night in the window of his New York store, the first computer store east of the Mississippi, and the NYPD had to put an end to it because people kept slowing down to gawk at all those color images.
Dazzler sales went over so well that Roger and Harry formed a new company to manufacture Altair plug-ins. They decided to name it after Crothers Memorial Hall, where they had lived during their undergraduate days at Stanford. Cromemco (Crothers Memorial Company) was the first of what would become an entire subindustry of firms manufacturing add-ons to extend the capabilities of existing personal computers.
At about this time MITS held the world's first microcomputer convention, called, strangely enough, the World's First Altair Convention. Located in the Airport-Marina hotel in sunny downtown Albuquerque, it was attended by an amazing number of people who came from all over the country to see what was going on.
The Altair was a success, but the paper tape BASIC and paper tape software were an abomination. One day Jerry Ogdin, a computer consultant, had come to me with the idea of storing digital data using two tones (one for a zero, another for a zone) on an ordinary voice-grade tape cassette recorder. In September of 1975 we ran a construction article on what we called HITS (Hobbyists' Interchange Tape System), after which a number of manufacturers started using their own approach to two-tone data recording. Wayne Green, who had just started Byte magazine, wanted all the manufacturers to get together in a neutral site and hammer out a cassette standard. The site picked was Kansas City, Missouri. We all met for a weekend, and after many loud and serious discussions the Kansas City tape "standard" was born. Unfortunately, it didn't last long; before the month ended, everyone went back to his own tape standard and the recording confusion got worse.
[HW0052][GDrive]
Why, then, isn't MITS one of today's industry leaders? Well, perhaps because its founder, Ed Roberts, was a better engineer than businessman.
When MITS struck it rich with the Altair, the small staff-less than ten people-geared up to handle the hundreds of orders that poured in. They set up manufacturing operations, software development and customer service, and even published one of the first computer magazines, Computer Notes. But problems arose because no one had ever made as many computers of one type. MITS had neither the experience nor its own capital to do the job, and in those days there were no venture capitalists breaking down doors to offer development money. Further, though computer hobbyists and potential dealers helped out with prepaid orders, Ed Roberts made some serious marketing errors. For example, MITS insisted that Altair dealers carry no other line of computers: "Ford dealers only carry Fords," Roberts declared, "and Altair dealers will only carry Altairs." When MITS could not deliver the computers, many dealers went out of business or dropped the Altair line.
MITS eventually did produce the Altair 8080B, a really fine computer with a good disk system and lots of good software including business applications. The company never solved its cash flow problems, however, and eventually Ed Roberts sold out to the Pertec Computer Co., which supplied the Altair disk drives. Ed retired from the computer industry to raise pigs in Georgia, then later decided to go to medical school.
Pertec, which had ambitions to become a major computer company, felt the name Altair was too identified with "hobby computers." The line was discontinued, and the Altair vanished from the market. When Pertec was itself bought out by Adler of Germany, the Altair name was condemned to oblivion. All that was left was Microsoft BASIC and the memory of the machine that started an industry.
STAN VEIT
THE RISE AND FALL OF THE ALTAIR
Though computer kit makers like Scelbi Computer Consulting, RGS Electronics and Martin Research actually preceded MITS, the Altair 8800 with its 5100 bus and Microsoft BASIC became the foundation of the personal computer industry. More Altairs were sold than any single computer ever designed up to that time (including the famous IBM 360).Why, then, isn't MITS one of today's industry leaders? Well, perhaps because its founder, Ed Roberts, was a better engineer than businessman.
When MITS struck it rich with the Altair, the small staff-less than ten people-geared up to handle the hundreds of orders that poured in. They set up manufacturing operations, software development and customer service, and even published one of the first computer magazines, Computer Notes. But problems arose because no one had ever made as many computers of one type. MITS had neither the experience nor its own capital to do the job, and in those days there were no venture capitalists breaking down doors to offer development money. Further, though computer hobbyists and potential dealers helped out with prepaid orders, Ed Roberts made some serious marketing errors. For example, MITS insisted that Altair dealers carry no other line of computers: "Ford dealers only carry Fords," Roberts declared, "and Altair dealers will only carry Altairs." When MITS could not deliver the computers, many dealers went out of business or dropped the Altair line.
MITS eventually did produce the Altair 8080B, a really fine computer with a good disk system and lots of good software including business applications. The company never solved its cash flow problems, however, and eventually Ed Roberts sold out to the Pertec Computer Co., which supplied the Altair disk drives. Ed retired from the computer industry to raise pigs in Georgia, then later decided to go to medical school.
Pertec, which had ambitions to become a major computer company, felt the name Altair was too identified with "hobby computers." The line was discontinued, and the Altair vanished from the market. When Pertec was itself bought out by Adler of Germany, the Altair name was condemned to oblivion. All that was left was Microsoft BASIC and the memory of the machine that started an industry.
STAN VEIT
It was at Kansas City that I first met Bob Marsh, who had formed a garage-based company in San Francisco called Processor Technology. Along with circuit designer Lee Felsenstein, he was making Altair memory boards and a graphics display board called the VDM-1, also for the Altair. Lee had worked for Marty Spergel, the driving force behind M&R Enterprises, and came through with plans for the Pennywhistle modem-the first hobby modem, published in our March 1976 issue. Now we computer hobbyists had a low-cost way to communicate over the telephone lines. Lee went on to design several trend-setting computers, including the portable Osborne.
I was still unhappy. The Altair needed a video display terminal with a self-contained keyboard. Like everyone else, I had been constantly startled by Don Lancaster's brilliant innovations over the years, and I knew he had just finished his TV typewriter. I went to Phoenix, loaded Don and his typewriter into the car, and took off for Albuquerque and MITS. One thing I must say for Don Lancaster and Ed Roberts: they both have very strong personalities. When I got them together in Ed's office, the clash was pretty fierce. Since the Altair and the TV typewriter were not compatible, something had to give. Neither man, however, would give an inch.
My next step was to talk to Bob Marsh of Processor Technology. It took a little doing, but I finally convinced him that a combination of his memory boards, his VDM-1 as the video display, plus an 8080, a power supply and the S-100 bus, would make a dandy "smart" terminal-or even a computer. We decided on the smart terminal approach, since I was fairly certain the magazine would not "buy" another computer. Lee Felsenstein did the preliminary design and, using one of Don Lancaster's approaches, came up with a computer. Steve Dompier and Gary Ingram did the software. Another software person, Gordon French, came up with the idea of wooden sides for the case-an odd first for computers.
In the summer of 1976 a new, easier-to-use computer was born, one with a self-contained operating system (no complex switches to get it started), built-in video capability, an integral keyboard and a small, typewriter-size enclosure. It was decided that this new approach would be called Sol. The story I was told by Marsh and Felsenstein was that if the strangelooking computer didn't fly, they had to have someone to blame it on ... guess who? At least they didn't call it the Les. Sol appeared in the July 1976 issue of Popular Electronics.
That summer there was also the famous Atlantic City Computer Conference at the snazzy Shelbourne Hotel/Motel. This was just about the first time almost all the microcomputer people got together in one place. It was a great show and the forerunner of the many computer fairs to follow.
During the 1977 First West Coast Computer Faire, I dropped in on the Heuristics Company to see what Horace Enea had wrought. His Speechlab plugin board would allow the user to actually talk to the computer, and the computer could "understand"! Not too much later Software Technology, an offshoot of Processor Technology, came up with a variation of Steve Dompier's music system (Dompier was the first to realize that microcomputers could make music) and produced a most marvelous sound system that was used in conjunction with an external audio amplifier. From now on, no microcomputer show would be silent!
The 1977 First West Coast Computer Faire (Jim Warren, chairperson) was a success in many ways. It was one of the first times such a wide variety of computer people got together in one place on the West Coast. Outside the Brooks Hall site of the show was parked a small van containing Mike Wise and his unique computer from the Sphere Company located in Bountiful, Utah. The one thing we remember about the Sphere was that its BASIC was s-1-o-w. Real s-1-o-w! The Sphere computer was never seen again: it was advertised and a couple were even delivered to computer stores, but very soon Sphere vanished from the face of the earth-a fate shared by many other pioneering computer models.
There were a lot of other developments over the years, some good, some transitory, none of them boring. Companies came and went, as did software. (Does anyone remember Target, the first personal computer game? Or Star Trek, with its umpteen versions?) Magazines also came and went. (Anyone remember ROM, with its column "From the Fountainhead" by a young writer named Adam Osborne?) Processor Technology vanished along with the late, great Sol and the unlamented Helios disk drive; Steve Jobs and Steve Wozniak came up with Apple I, a computer on a single circuit board that would lead to bigger things; Bob Suding of the Digital Group out in Denver came up with some good hardware, unfortunately too far ahead of its time.
A couple of guys in New Jersey, Roger Amidon and Chris Rutkowski, came up with a "supercomputer": the General, with its superb software. Although the General also soon folded its tent, the idea of this machine recently returned when Roger and Chris, using the Rising Star marketing firm as a base, introduced the Epson QX-10 with Valdocs word processing software-the most user-friendly computer system I've seen as of this writing and, incidentally, the machine I used to compose this account.
This just about brings me to the end of my musings about "the good old days"-to the end of 1977, just two years after the Altair. I personally don't believe we shall ever again see such an outburst of raw talent. They were great times. (If I missed any important event or name, forgive me, fellows, I am getting old.) I salute that long-haired, blue-jeans-and-T-shirt bunch, bearded or not shaven at all, fueled by hamburgers and Anchor Steam beer (I didn't forget, Steve), limited only by their imagination. They left the legacy that a handful of guys with an idea can change the world ... because that's exactly what they did. Just look around.
[HW0053][GDrive]
When I finally got one, of course, there was precious little I could do with it. My Altair turned out to be just a box with toggle switches and neat rows of red LEDs (light-emitting diodes) decorating the front panel. The switches were its only input device; the LEDs were its output, glowing and darkening in patterns that showed what you had input from the switches and what the computer had done as a result. Both operated at the same simple-minded level as the computer itself, in binary numbers built up of 1s and 0s. A "1" was entered by raising a switch, a "0" by lowering it. The corresponding LEDs glowed for each "1" and darkened for each "0."
A one-byte program instruction, nothing more arduous than STOP, took eight switch settings.
The Plug-In Problem
Luckily, there was a world beyond the binary level. I went out and got a "terminal," with keyboard and video display screen, but then found nothing on the Altair to plug it into. What I needed was an I/O (input/ output) circuit board through which the computer and terminal could communicate. The Altair had about a dozen slots where you could plug in I/O and other boards. Put a 25-pin connector into one of the oval holes in the computer's back, run a cable from the I/O board, and you had a place to plug in the terminal.
Problem: typing on the terminal had no effect on what the Altair did. Just as nice children don't speak until they're spoken to, computers don't communicate with terminals until a program has told them they can and how to do it. There was such a program in octal (base-8) numbering that you could translate into binary and toggle in from the front panel of the Altair. Unfortunately, the program was several hundred bytes long; at eight bits per byte, this meant well over a thousand switch-flicks before the program was in the machine. Since a computer's random access memory becomes amnesiac the instant its power is shut off, you'd have to toggle in that program every time you wanted to use the machine. And if you made just one of those thousand switch-flicks wrong, the program wouldn't run-or would run amok, randomly changing the bits you'd toggled in correctly.
The solution was to put that program, and any others you needed regularly, into an EPROM (erasable, programmable, read only memory), which would hold its contents even when the computer was shut off. A whole set of such programs fit easily into just two EPROM chips. Naturally the Altair had no place to plug in those chips, so I had to buy a Cromemco Bytesaver board to hold them and plug it into the Altair's bus. With those programs, typing in instructions like C2 D5 01 ("If the zero flag is not set, jump to the program steps at memory location 01D5") was simpler than setting switch sequences of 11000010 1101010 00000001. Writing programs in tiny steps of arbitrary symbols, however, was still infuriatingly slow. What I needed was a "high-level" programming language.
By that time the Altair could run an abbreviated BASIC, the first product of a tiny new firm called Microsoft. It was only available on punched paper tape, which required a special paper-tape reader, but for once I didn't have to buy any new equipment. I had a friend with a teletype-a printing terminal that could also read and punch such tapes. I ordered BASIC and my friend read it into his machine, then rerecorded it onto a tape cassette. I might not have a paper-tape reader, but I did have a cassette recorder.
Still Plugging Away
Not surprisingly, the Altair had no place to plug in the cassette. Now what I lacked was a board that would translate between computer and cassette deck. With this I would have a fully functioning system, including all the major parts a computer needs: a keyboard and screen (on the terminal), mass storage (the cassette), a processor, and both ROM (built-in program) and RAM (user-programmable) memory. But the Altair came with 4K of RAM memory and the BASIC interpreter took up 8K, not counting the program you then wanted to run. The solution here was to plug in still more memory boards.
In those early days, few programs were readymade, in part because not all the programs marketed for the Altair were available in the same tape format. Besides, there simply weren't that many to choose from. Then along came the next generation of personal computers: machines like the Radio Shack TRS-80 Model I, the Commodore PET and the Apple II, with resident programs in permanent memory, cassette connections, keyboards and (save for the Apple) screens built in. Not only that, but they had BASIC built in, so you could run your language immediately-no waiting while you loaded it from a tape.
In principle, they were little different from my old Altair. The major difference was that these computers didn't require months of learning and searching for parts before you could use them. All you had to do was plug them in ...
IVAN BERGER, technical editor of Audio magazine
Come A Long Way
The horse-and-buggy days of home computing were not all that long ago. In fact, less than a decade has passed since I first read about the Altair and began thirsting-nay, lusting-for a computer of my own.When I finally got one, of course, there was precious little I could do with it. My Altair turned out to be just a box with toggle switches and neat rows of red LEDs (light-emitting diodes) decorating the front panel. The switches were its only input device; the LEDs were its output, glowing and darkening in patterns that showed what you had input from the switches and what the computer had done as a result. Both operated at the same simple-minded level as the computer itself, in binary numbers built up of 1s and 0s. A "1" was entered by raising a switch, a "0" by lowering it. The corresponding LEDs glowed for each "1" and darkened for each "0."
A one-byte program instruction, nothing more arduous than STOP, took eight switch settings.
The Plug-In Problem
Luckily, there was a world beyond the binary level. I went out and got a "terminal," with keyboard and video display screen, but then found nothing on the Altair to plug it into. What I needed was an I/O (input/ output) circuit board through which the computer and terminal could communicate. The Altair had about a dozen slots where you could plug in I/O and other boards. Put a 25-pin connector into one of the oval holes in the computer's back, run a cable from the I/O board, and you had a place to plug in the terminal.
Problem: typing on the terminal had no effect on what the Altair did. Just as nice children don't speak until they're spoken to, computers don't communicate with terminals until a program has told them they can and how to do it. There was such a program in octal (base-8) numbering that you could translate into binary and toggle in from the front panel of the Altair. Unfortunately, the program was several hundred bytes long; at eight bits per byte, this meant well over a thousand switch-flicks before the program was in the machine. Since a computer's random access memory becomes amnesiac the instant its power is shut off, you'd have to toggle in that program every time you wanted to use the machine. And if you made just one of those thousand switch-flicks wrong, the program wouldn't run-or would run amok, randomly changing the bits you'd toggled in correctly.
The solution was to put that program, and any others you needed regularly, into an EPROM (erasable, programmable, read only memory), which would hold its contents even when the computer was shut off. A whole set of such programs fit easily into just two EPROM chips. Naturally the Altair had no place to plug in those chips, so I had to buy a Cromemco Bytesaver board to hold them and plug it into the Altair's bus. With those programs, typing in instructions like C2 D5 01 ("If the zero flag is not set, jump to the program steps at memory location 01D5") was simpler than setting switch sequences of 11000010 1101010 00000001. Writing programs in tiny steps of arbitrary symbols, however, was still infuriatingly slow. What I needed was a "high-level" programming language.
By that time the Altair could run an abbreviated BASIC, the first product of a tiny new firm called Microsoft. It was only available on punched paper tape, which required a special paper-tape reader, but for once I didn't have to buy any new equipment. I had a friend with a teletype-a printing terminal that could also read and punch such tapes. I ordered BASIC and my friend read it into his machine, then rerecorded it onto a tape cassette. I might not have a paper-tape reader, but I did have a cassette recorder.
Still Plugging Away
Not surprisingly, the Altair had no place to plug in the cassette. Now what I lacked was a board that would translate between computer and cassette deck. With this I would have a fully functioning system, including all the major parts a computer needs: a keyboard and screen (on the terminal), mass storage (the cassette), a processor, and both ROM (built-in program) and RAM (user-programmable) memory. But the Altair came with 4K of RAM memory and the BASIC interpreter took up 8K, not counting the program you then wanted to run. The solution here was to plug in still more memory boards.
In those early days, few programs were readymade, in part because not all the programs marketed for the Altair were available in the same tape format. Besides, there simply weren't that many to choose from. Then along came the next generation of personal computers: machines like the Radio Shack TRS-80 Model I, the Commodore PET and the Apple II, with resident programs in permanent memory, cassette connections, keyboards and (save for the Apple) screens built in. Not only that, but they had BASIC built in, so you could run your language immediately-no waiting while you loaded it from a tape.
In principle, they were little different from my old Altair. The major difference was that these computers didn't require months of learning and searching for parts before you could use them. All you had to do was plug them in ...
IVAN BERGER, technical editor of Audio magazine
Page updated
Report abuse