PC Museum (3) MITs Altair 8800

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Albuquerque, New Mexico Micro Instrumentation Telemetry Systems（MITS） The production of Altair 8800 Many people think it is the first “ Personal computer ”—— A cheap and easy to buy computer .

At this time , Individuals do not have computers or electronic stores to buy their own computers . The only option is to build your own system from plans and designs published or sold in magazines and other sources . Find and obtain all parts required for assembly , It becomes a personal responsibility .

Altair 8800 First appeared in 1975 year 1 The month and 2 Of the month 《 Popular electronic magazines 》 On , Although this early design bears little resemblance to the final version released a few months later . Before that ,MITS To sell calculators and rocket model components （ telemetering ） Famous for .

Only 439 dollar ,Altair 8800 For the first time, everything is included in one package —— Assembly instructions 、 Metal shell 、 Power supply and manufacturing “ The most powerful computer shown as a construction project in any electronic magazine ” All plates and components required .

After many days and nights of careful welding and assembly , Is expected to create a job Altair 8800. Only real hackers will make such efforts .

MITS Ed, the owner and President of · So is Roberts Altair 8800 The designers of .

Roberts （Roberts） With 75 At the price of US dollars, we bought a large number of powerful new Intel 8080 CPU, At that time, their selling price was usually 300 More than $ .

reportedly , The low price is caused by appearance defects or other substandard chip quality problems , But in 1984 year 10 month 《 Modern electronics 》（Modern Electronics） Interview （ This is another version ）,Ed Roberts Express , They are fully functional 、 Full specification chip , And the low price is entirely due to MITS yes 8080 CPU The largest buyer of . To 1977 year , The price has been reduced to less than 15 dollar .

The system on the right has two additional circuit boards installed , but CPU Card is the only circuit board that needs a working system .

Whole Altair 8800 The system consists of a metal shell 、 A power supply 、 A front panel with a switch and a passive motherboard with an expansion slot . All the circuits ——CPU And memory —— It's all on the card , Insert the card into the expansion slot ,MITS be called “Altair Bus ”.

This has achieved a very simple and popular computer design method . Manufacturers are Altair Under the bus standard （IMSAI 8080 Is the first ） My first imitation model .Altair Bus has become the industry standard , but MITS I don't like renaming it to S-100 Bus （ It has 100 One pin ）.

Because there is no cheap keyboard or monitor , The user must initially flip the switch on the front panel , Write your own program in machine language , And look at the... On the front panel LED Lights up in response to their orders .

because S-100 Flexibility of the bus , Many expansion cards will be released soon , Including keyboard interface 、TTY、 Monitor 、 Printers and data storage , Greatly increased Altair The practicality of .

MITS Other offers Altair card ：

Function	kit price	assembled
1K static state RAM	$97	$139
2K static state RAM	$145	$195
4K dynamic RAM	$195	$275
serial interface	$119	$139
Parallel interface	$92	$114
Cassette interface	$128	$175

bill · Gates and Paul · Allen saw an opportunity , Write the Altair BASIC, A real programming language .Monte Davidoff Contributed mathematical routines , Include Altair 4K BASIC Floating point routines .Altair BASIC The price is 500 dollar , It's very expensive , But with Altair The computer 、 Interface board and 8K When you buy memory together, you only need 75 dollar .

Not long after , Gates and Allen set up their own company - Microsoft , And sell it Altair BASIC For their first product .

Why is the computer named “Altair( Altair )”？ The name is decided by the popular electronic magazine , But there are two versions of this story ：

The first and most popular saying is , The name comes from the TV series 《 Star Trek 》—— Obviously false , But it sounds good . The story is ,Les Solomon（ at that time ） yes 《 Mass electronics 》 The technical director of the magazine （ And a great storyteller ）, He asked his daughter a name , She suggested calling “ Altair Altair”, because “ This is where enterprises are going in this concentration ”—— She should be watching science fiction TV series 《 Star Trek 》.《 Star Trek 》 Only one episode mentioned Altair ：“ Crazy time ”, The first 34 Set - Original broadcast date ：1967 year 9 month 16 Japan .

in addition , Andrew Forrest ·M· Mimus III is 1984 year 11 Published in 《 Creative computing 》 Pointed out in ,Altair It will initially be named PE-8（ Popular Electronics 8 position ）, but Les Solomon I think the name is rather boring , therefore Les,Alexander Burawa（ Associate editor ）, John · McVeigh （ Technical editor ） decision “ This is a stellar event , So let's name it after the star .” McVeigh proposed “Altair ”. actually , There is a star called Altair , It is the first in the sky 11 The brightest star .

2005 year 1 month , John · McVeigh （JohnMcVeigh） Wrote me a letter , Confirmed the second statement , And recall that in PopularElectronics Good time ！

This is the real beginning of the computer age ！

1975 year 9 month , The first phase BYTE Magazine distribution . They proudly wrote on the cover ：“ The computer ： The greatest toy in the world ！”.

Even though MITS More and more advanced models have been developed , And deliver thousands of sets every month Altair Computer system , But the company is still 1976 It was sold to Pertec.Pertec Continue to produce Altair , But it's bad , In a few years ,Altair Series of computers disappeared in history .

MITS Altair 8800
Introduced:	January 1975
Available:	February 1975
Prices:	US $395 as a kit
	(prior to March) US $650 assembled
How many:	estimated 2000+
CPU:	Intel 8080, 2.0 MHz
RAM:	256 bytes, 64K max
Display:	front panel LEDs
Controls:	front panel switches
Expansion:	Altair-bus card-cage
Storage:	paper tape, cassette or floppy drive
OS:	CP/M, BASIC