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This is an old revision of this page, as edited by WardXmodem (talk | contribs) at 17:29, 2 September 2012 (/* Continuing the article with some details? REALLY minor - e.g. closing ) etc.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

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Weasel Words?

I've spotted some phrases such as "Programming the Altair was an extremely tedious process" and "No particular level of thought (or rushed design) went into the design", which appear to be weasel words. Any confirmation on this? 220.236.18.233 08:02, 26 November 2006 (UTC)[reply]

Pretty much the whole article is in the wrong tone. :-( As the tag says, it's more like reading a mag than an encyclopedia. The weasel words is just part of it. — Northgrove 08:17, 15 August 2007 (UTC)[reply]

Altair 8800

--141.149.132.54 14:36, 10 Mar 2005 (UTC)I am doing a project on the Altair 8800. I wondered if this was the FIRST Altair design. If you know, post it on this page!

Toy or machine?

Right now the article just describes 8800's history. It doesn't say anything about the function. Right now, I don't see any useful aspects in this machine. It can only make LEDs blink. May it be used for something more useful? --134.91.77.152 11:51, 19 December 2005 (UTC)[reply]

I don't think the LEDs were just used for blinkenlights; they were actually used for data output. Personal computers haven't always had monitors. That said, I think there were add-on cards for Altairs which allowed them to be hooked up to CRT terminals.
Whoops, when I removed the signature from the post above I forgot to add in the edit summary that it was in preparation to vanish. Consider this one the same.

Yeah I've been scratching my head over this for a long time. I know that the lights must have meant something, binary values of each decimal number or something? What could the machine do, what was it's killer application besides BASIC. 86.143.234.154 07:44, 2 September 2006 (UTC)[reply]

In the January 1975 Popular Elecronics article, a sidebar is dedicated to listing possible applications. (visible at http://www.computermuseum.20m.com/images/popelec/Page%2038.jpg) JimH443 23:12, 12 May 2007 (UTC)


A stock Altair 8800 (with no additional IO cards) appears to be a very limited beast. Though the article's description of the programming task is essentially correct (flipping switches to input the binary opcodes), the description of the output isn't quite spot-on. The LEDs of the Altair are connected directly to the address bus and data bus. So, rather than writing a program to "make the lights flash", when the CPU was executing instructions, the lights would flash wildly, reflecting whatever signals were present on the bus. If the program wasn't branching, you could discern the binary incrementing of the address lines, but that's about it.

When the user was programming the Altair, the CPU is halted. The RAM in the Altair was Static RAM, and didn't need to be refreshed. Essentially, during programming, nothing is happening inside the machine. After flipping the switches to specify the next instruction, the user depressed the (spring loaded) "Deposit" switch. This action manually clocks the bus 1 cycle, thereby latching that byte into the specified RAM location.

As I understand it, a common early Altair programming technique was to write a program that performed some calculation and then wrote the result into a certain RAM location (ofter looping and doing this operation many times over...why not?). The user would then halt the program (and indeed the CPU), and then use the switches and LEDs on the front panel to examine the contents of the target RAM location.

Altair basic

The Altair basic section is kind of confusing.--Gbleem 20:24, 19 December 2005 (UTC)[reply]

Price?

I don't see the machine's price mentioned anywhere here... --Golbez 16:02, 14 July 2006 (UTC)[reply]

According to http://www.computermuseum.20m.com/popelectronics.htm, "... can be built for under $400" (this page links to an image of the article taken directly from the magazine) JimH443 23:06, 12 May 2007 (UTC)[reply]

Here is a link to the March 1975 price list.[1] The Altair 8800 kit version is $439, the assembled version is $621. A working system would cost around $2000 -- SWTPC6800 23:20, 12 May 2007 (UTC)[reply]

I bought mine in 1975 for the "Cover of Pop tronics" price of $395. At least that's what I recall! WardXmodem (talk) 17:21, 2 September 2012 (UTC)[reply]

Solomon

Who is Solomon? —The preceding unsigned comment was added by 196.25.255.246 (talk) 16:34, 12 December 2006 (UTC).[reply]


Solomon

It seems that Solomon is the young daughter of the 'Popular Electronics' magazine editor as mentioned in the Old-Computer site at http://www.old-computers.com/museum/computer.asp?st=1&c=62. --Jtravis06 07:18, 16 December 2006 (UTC)[reply]


First World Altair Computer Converence held in Albuqerque New Mexico on March 26-28 1976.

Report on a seminar held on Saturday evening.

MITS Computer Notes, April 1976, Page 7

Computer Power of the Future

Annette Milford

Les Solomon, editor of Popular Electronics, told the Saturday night crowd of 700 that five years ago he and Ed Roberts, MITS' president, were speculating about whether it might be possible to sell 200 Altairs and break even.

Les Solomon entertained a curious audience with anecdotes about how it all began for MITS. The name for MITS' computer, for example, was inspired by his 12-year-old daughter. "She said why don't you call it Altair--that's where the Enterprise is going tonight."

SWTPC6800 02:41, 26 December 2006 (UTC)[reply]

Spoiler

The spoiler template appears to be of little use: the warning is placed before it is clear which movie is spoiled. But then again, maybe the fact that the Altair 8800 appears in Malcolm in the middle is the whole spoiler? ElMorador 11:30, 19 December 2006 (UTC)[reply]

Sources

I don't see any. —Preceding unsigned comment added by 64.81.227.133 (talk) 21:22, 14 October 2007 (UTC)[reply]

Memory size?

How much memory was there in that thing? The article doesn't say. --207.176.159.90 (talk) 03:15, 19 December 2007 (UTC)[reply]

The original Altair 8800 came with 256 bytes of RAM. To get a useful system you would need to purchase additional memory boards. The early boards would hold 4K bytes and soon there were 8K and 16K boards. The Intel 8080 CPU would address 64 K bytes. A system that used audio cassettes for data storage was usable with 8K of memory. A floppy disk system would need a least 12K or 16K. In December 1976 a 4K RAM board cost around $160. -- SWTPC6800 (talk) 05:21, 19 December 2007 (UTC)[reply]

Publication date

The introduction date for the Altair computer has been reported as December 19, 1974. I have never found a source for that date. The June 1975 issue has this:

  • Ogdin, Jerry (June 1975). "Computer Bits". Popular Electronics. 7 (6). New York: Ziff-Davis: p. 69. {{cite journal}}: |pages= has extra text (help) "The break through in low-cost microprocessors occurred just before Christmas 1974, when the January issue of Popular Electronics reached readers … "

I made a visit to the Copyright office in the Library of Congress to find the correct date. The reading room is LM-404 in the James Madison building; 101 Independence Avenue, S.E., Washington, D.C. The pre 1978 records are hand written on 3 by 5 cards and stored in card catalogs drawers, just like an old library. The published date is when it went to the printer, not when it was mailed to the reader.

The January 1975 issue of Popular Electronics was published on November 29, 1974; registration number B99920. The January 1975 issue of Radio-Electronics was published on December 19, 1974; registration number B992753. -- SWTPC6800 (talk) 01:09, 22 May 2009 (UTC)[reply]

Continuing the article with some details?

Is it appropriate based upon other TALK that details be added to the article?

Let me just type off the top of my head a possible addition to the article, though it would read more like a BLOG than an encyclopedic entry - but I think Wikipedia is -- or I think Wikipedia should be -- more "friendly" -- as long as it is 100% factual.

The Altair's appeal, was not in what it could do, but in what it was - it was -- at $395 -- an affordable computer. Some people purchased it with no purpose in mind except to "own a computer", and "play with it".

With your $395 purchase for the kit, you got the chassis with front panel, power supply, CPU board, and I believe (need to check sources) 2K static RAM memory board, but populated only with 256 bytes. need confirmation - I recall 2K, previous said 256 bytes the chip was a 2102, which was 1024 x 1, so ... I can't remember that initial 256 bytes, i.e. where it was etc. Sorry.

Your only input with the base configuration above was the front panel switches, and the output was the LEDS which were hooked to an 8-bit output port.

Nevertheless, you could do a lot with nothing more:

  • Even without an Altair you could learn the 8080 instruction set
    • ...but WITH ONE you WANTED to learn it
  • Once you learned the front panel:
    • how to address memory
    • how to store bytes
    • how to read back bytes
  • you could enter small programs, address the first byte of them, and press "run".

If for example, you wrote a program (pseudocode):

 load a value of 23 hex into the accumulator
 output the accumulator to the port which addresses the front panel
 halt  

When it ran, and the lights showed

 _ _   # _ _   _ # # <= for they were laid out in an octal grouping

then you had the thrill of having learned enough of a new computer language, how to program and run it, and get the right answer.

It would be significant to know (1) how many never finished the kit; (2) how many finished it but never played with it; (3) how many were satisfied with it in its base configuration with just switches and LEDS, and (4) some examples of the height to which it rose (such as being the basis for my inventing/programming the Xmodem protocol, and with Randy Suess ably handing the hardware, inventing and programming the first BBS).

I could go on with a discussion of the options available for it in the early years, including the pitfalls (very finicky 4K dynamic RAM board), the lack of ROM so you had to "switch in" your program -or- a bootloader for some other device (from hand pulled paper tape in an optical reader, to full blown operating systems).

Then there was the huge explosion in boards for the Altair bus, later renamed S-100 when "clone" computer manufacturers supported it but didn't want to advertise the competition.

Among the most significant (TO ME, so not appropriately "encyclopedic"

  • Processor Technology Video Display Module (VDM)
    • Memory-mapped 16 x 64 character display
  • (Processor Technology?) 3P+S
    • Three bidirectional parallel ports, and a serial port, creating the foundation for most who used "serial terminals" as their "console" particularly for the CP/M operating system.
  • additional memory boards (after the reliability problems in the Altair 4K dynamic memory board)
  • various EPROM boards for their ability to hold boot loaders for peripherals.


I could go on for hours. but won't. Not without some idea as to whether my history in buying, building, and enhancing my Altair, is of interest to anyone in the context of "Wikipedia" where it was commented articles should be encyclopedic. This implies Wikipedia is NOT a place for say a blog, or a dry product review, etc.

Let me know your thoughts. WardXmodem (talk) 17:17, 2 September 2012 (UTC)[reply]