IT Crowd Altair - Lifting the Lid - Computerphile

What's inside the case of this 40yr old Altair? Jason from the Centre for Computing History opens up this early machine to find some surprising changes.
Main Altair Film: • Computer That Changed ...
Most Difficult Program: • The Most Difficult Pro...
Pushing the Atari Limits: • Pushing the Atari Limi...
Arduino Hardware: • Arduino Hardware - Com...
Centre for Computing History: www.bit.ly/C_ComputerMuseum
/ computerphile
/ computer_phile
This video was filmed and edited by Sean Riley.
Computer Science at the University of Nottingham: bit.ly/nottscomputer
Computerphile is a sister project to Brady Haran's Numberphile. More at www.bradyharan.com

[@stachowi]

FYI... Reason why the one on the cover looks different is because the real #1 was lost during shipment, the one on the cover is a non-working version (just the shell). Paul Allen's autobiography is my reference, great book by the way especially about the beginning of the Altair.

[@MartKencuda]

Where are the holes for those buttons on his sweater?

[@PublicCommerce]

Rabid Rabbit Rabbi A good quality sweater will come with a few spare button holes in case some of the originals fall off.

[@thelol1759]

Rabid Rabbit Rabbi They're behind the flap, so you dont see the buttons when its buttoned up.

[@benjaminhanke79]

I just realized how much I got distracted by that.

[@stevenjlovelace]

This talk of CP/M makes me want to see a Computerphile video about Gary Kildall.

[@TheChipmunk2008]

Steve Lovelace Yes. This!

[@wisteela]

Superb. I've never seen on ungraded with a hard drive before. Great bit of history there, and the IT Crowd connection makes it even better.

[@squidcaps4308]

I'll bet that if you re-upload this one and use title "IT Crowd Altair" you'll get loads more hits ;) The show is more known than Altair and for me the importance of this machine doubled, and i'm really in to old computers..

[@Computerphile]

SquidCaps renamed :) >Sean

[@squidcaps4308]

***** Awesome, that made my day complete and it was pretty damn good one to start with :)

[@maciej-36]

***** So IT Crowd is coming back on this channel? Hoooorey! :D

[@slaquers]

Love this Altair video!

[@kevincozens6837]

I kept my copy of the January 1975 issue of Popular Electronics. I used to have the start of an S-100 bus system but never finished putting it together. I no longer have the motherboard, the power supply, or the 8" floppy disk drives for the system. I still have an 8080 CPU card, a memory card, and a video adapter card. I also an original set of CP/M manuals. I also have (or had) an original 8" floppy of CP/M from DR. A few years ago I saw an Altair 8800 at a flea market selling for $4,000 with a couple of additional cards inside it beyond the basic boards. BTW, DOS is a bit like CP/M as it was loosely(?) based on CP/M.

[@shayneoneill1506]

I remember being a little kid in about 1979 and my uncle ., who was doing a maths degree at the time (Really the only way to study computers in the 70s) bringing one of these home. It was a fascinating box, but a bit confusing as a kid. Eventually we got a computer called a "Dick smith wizzard" , a 4K australian computer, and a few years later a C64

[@edgeeffect]

Brilliant to see an Altair... but I kept getting distracted by the BBC Micro behind him.

[@WillBreaksStuff]

Your camera work is akin to a chipmunk on hardcore street drugs. I came here to see the machine!

[@JerryWalker001]

Hi, I know it is a long time since you posted this video but I am in the process of making clone boards for the 8800 and I am trying to find a dimensional diagram for the front panel layout. DO you happen to have such a thing or would you be able to take a front on photo with a ruler up against the panel so that I can use it to determine the switch and LED locations. Really like the videos by the way.

[@realraven2000]

More specs, please? How much ram on the ram expansion board? I remember soldering / socketing big Ram chips like that myself... How big was the hard drive 2 Mbyte or more? I think the quantities are quite important to put things into perspective.

[@Computerphile]

Realraven2000 We did investigate the HDD size but sadly WD have re-used the model number, think it was WD1000 from memory. Centre For Computing History may be able to help further >Sean

[@Landrew0]

The childlike enthusiasm is refreshing.

[@sparrowthesissy2186]

I wish there was some kind of equivalent of the Altai 8800 as a toy set for kids. A snap-together computer with some visual programming on it might make some money. I suppose that's kind of what the Lego robotics stuff is, though.

[@trstmeimadctr]

That exists. It's called Kano. There is also the MakeyMakey

[@johankotze42]

Aaah! I did notice it on The IT Crowd.

[@SapphireCrook]

Wait, that's 40 years old? That's what they looked like 40 years ago? Geezes I'm just baffled. If this is 40 years of development, who knows what we'll have in 20 years.

[@Hepglon]

***** With silicon atleast. There are other materials gearing up to replace silicon however. :)

[@rogerwilco2]

I have an ICL machine form 1980 or so, with 7 serial terminals, a full size 20 MB winchester, 2x 256 kB RAM, a 720 kB 5.25 inch floppy drive, a 80186 CPU, a Xebex 1210 disk controller, all connected on a SASI bus and running CPM/86. I can't look up the model number right now, it's in the attic, I'm working from memory. It was used in a typography office.

[@WAQWBrentwood]

IIRC the Z80 cpu is still in production and is used in embedded systems!

[@bman12three43]

and in TI-84s

[@WAQWBrentwood]

TheAlternateAir Cool! I was a long time our of school by the time graphing calculators came out, But I have to get a TI - 84 just to have a spiritual connection to the the Sinclairs I started on :)

[@DrMcCoy]

There also was a popular-ish build-your-own computer thing in Germany, the MOPPEL. That one was in the early 80s, though, and ran on an 8085: de.wikipedia.org/wiki/Moppel

[@p8651]

Very cool! :)

[@mUbase]

I want to have a go on one of these. I was born in 1975 so started on the zx81 and the bbc. :)

[@jakewisher4623]

I got the little "in joke" on the IT crowd (I wondered why they pointed out a sinclair zx81, but not the altair!)

[@ASquared007]

Is that a Google Cardboard app running on the TV behind you (via Trinus Gyre)?

[@randomaccessbrains]

ASquared007 Probably oculus but trinus gyre is awesome too (if you can get it working)

[@grn1]

@@randomaccessbrains There's an Oculus sign above the monitor.

[@andljoy]

The Z80 crops up everywhere you look. Its still made today, right now somewhere they are spinning silicon for one of them bad boys, thats one hell of a run. Don forget the Z80 rule, if it exists there has been a z80 in it at some point in its life , if not to this day.

[@DrMcCoy]

Andrew Joy The TI-83+ graphics calculator had a Z80. That was my introduction into assembly programming 15 years ago when I got one for school. :) The original gameboy also had a (modified) Z80, IIRC.

[@rsjohan838]

***** My TI-84+ has one as well. I was really surprised when I found that out, since it's such an old chip design, and I paid quite a bit of money for it.

[@sporkafife]

rsjohan838 them damn graphics calculators are ridiculous! Usually, computer power increases and computers with the same power get cheaper. Not bloody graphics calculators! You're still forced to pay loads of money for hardware that has hardly changed in 20 years :P

[@DarrenLandrum]

sporkafife Consider this: graphing calculators are required purchases for students taking math classes at university. Once you think of these calculators as being like textbooks, their price is easy to understand.

[@mUbase]

Ive got a Micro professor. :)

[@JanBabiuchHall]

What's the Polish site he mentioned?

[@shayneoneill1506]

Concurrency on a Z80? I'm not sure about that. I know there was a concurrent x86 version of CP/M, but I'm not sure about the Z80. Its possible that this multiple serial port setup was used for a single user with multiple serial prehipherals . Possibly industrial control? edit: Ok, on further research there was something called "TurboDos" , a multitasking version of CP/M, and another OS called EUMEL which ran on Z80s and supported concurrency. TurboDos however required special hardware, as rather than multitasking on a single processor, it needed multiple processors, so was more of an early version of clustering. EUMEL used some strange java style VM type arangement and I dont know if it had much impact on the world outside of academia. There was also something called MP/M which I don't know much about.

[@HarleyPebley]

Shayne O'Neill Concurrency on a Z80? Absolutely! There were operating systems that supported multiple users on Z80 hardware. Oasis (later renamed Theos) and Pick come to mind. I had customers with 8 simultaneous users (plus additional peripherals) on Z80 based machines.

[@ianwalker6546]

Shayne O'Neill You can do co-operative multitasking on anything. For pre-emptive multitasking you need hardware designed for the job. Windows worked the co-operative way up until v3

[@HarleyPebley]

RaymondHng Ah, ok. I never worked on Pick myself. Only knew of it as a competitor to Oasis in some markets. Thanks for the clarification. Cheers.

[@RaymondHng]

Harley Pebley The Pick operating system's main competition was Unix back then. Pick was suited for vertical-market business applications while Unix was suited for scientific applications. In the '80s, Pick was a database management system that was also the native operating system. It continues to live on to this day under different trademarked names as a database under a host operating system such as Unix, Windows, Linux, MS-DOS, etc. as well as a native operating system.

[@azmanabdula]

Could someone tell me roughly how much money went into upgrading this Altair?

[@typograf62]

"I had to have it!" Naturally so.

[@markcummins6571]

I assembled the basic kit for my boss in 1975 or 1976. It worked the first time I turned it on. Thank goodness as I really did not know anything about the programing at that time. It only had the front switch board and the board on the bottom (CPU and system) no S100 slots. I also built and RS232 interface for the keyboard and video modulator and an audio FSK modulator for streaming to an audio cassette recorder/player. I started working for DEC in 1979 and found out the software end of things. DEC gets very little credit for its contribution to the hobbyist computing world but I know first hand that it was immense. If you get a chance I would love to see a video of the base system unit that I think you referred to please?

[@PeterWalkerHP16c]

+Mark Cummins I think DEC gets loads of (silent) kudos in the hobbyist area. So many people had exposure to the PDP series. I mean Gates used a -11 or -10 to write BASIC for the Altair. SpareTimeGizmos even had kits to build an SBC -8 for a while.

[@markcummins6571]

I saw a picture of him beside an 11/23 with RX02 floppies supposedly at his University. If it was correct I suspect he was running a version of RT11. I started with version V3b and if was very good to learn on. I currently own an 11/23 and 11/73 in the same type of cabinet. I have a second cab with 3 RL02's. I want to power it up again but it has not seen coulombs supplied to the power input since 2000. I suspect it with not rise easy.

[@FireicerCooper]

The born ultimatum of the PC

[@kurtbuck99]

The capacitors on that are about as big as the ones on my Pioneer SX-1050. Looks like it puts out around 100 watts per channel...

[@1ebutuoy2]

Back then I used to build multi user accounting systems with s100 computers and turbodos.

[@shayneoneill1506]

1ebutuoy2 Those things used multiple Z80s to achieve their concurrency right?

[@Jaffaparty]

Is this #DanTheMan 's Dad? ;)

[@BlackEpyon]

You guys need to do the IBM PC and the Tandy 1000.

[@BlackEpyon]

MichaelKingsfordGray But was it PC-compatible? :P

[@BertGrink]

+BlackEpyon In 1977? Highly unlikely, as the original IBM PC only appeared around 1980~81.

[@BlackEpyon]

Gert Brink Nielsen The IBM PC was the original standard. My first machine, the Tandy1000 HX, was PC compatible.

[@StephenTack]

So, I bet the documentary mentioned is Triomph of the Nerds - by Robert X. Cringely, who (IIRC) is also the Silicon Valley journalist who owns the Altair No. 2?

[@HailAnts]

Yes, and according to Cringely serial number one was lost in the mail, so he owns essentially the first home computer (serial #2)...

[@richardjames712]

HailAnts i wouldn't believe Cringely if he claimed Monday follows Sunday.

[@typo148]

ooops, you said the Z80 was a Mos-Tek chip. Nope it was Zilog of course.

[@PeterWalkerHP16c]

+typo148 MK3880P

[@nilswegner2881]

typo148 maybe that specific chip was a mos-tek. The z80 has been manufactured by a lot of different companies

[@lotrbuilders5041]

DJ Slinus all early chips were actually produced by mostek, since Zilog didn’t have any chip fans yet

[@BigMiau]

Who's playing Sonic in the background? xD

[@explosiveegg3920]

@Rabid Rabbit Rabbi silly, they're spare buttons. In case one falls off and you lose it.

[@charliefoxtrotthe3rd335]

I am trying to figure out how I would play Mine Craft on it

[@hellrocker1212]

Any one else see them running minecraft in the background for 3D.

[@TrolleyMC]

HellbentMadness Thats not minecraft.

[@bolognahero]

2:36

[@hurktang]

Hey ! Don't put your fingers on the contacts. There is plenty of room on that card to put your wet fingers on !

[@andro7x]

USD $1111 ? Wow, that is a LOT of money.

[@SapphireCrook]

andromedar1977 That's an awfully SPECIFIC amount of money.

[@andro7x]

Sapphire Crook Agree, and i mised a "1", so it's 11111 :)

[@strangelimey]

I do wish the camera man would stop all the shaking and snap-zooms. This is not an action movie...

[@skeggjoldgunnr3167]

It was an action movie! Who needs high speed chases, scantilly clad women and big fiery explosions when you've got all THIS!!!

[@xoom1712]

Am I really the only person who saw the title and thought: "ASSASSIN'S CREED!"???

[@proxy1035]

I wish i had one... jus tfor the jokes... but man... i need to save up for like a year to affort one

[@hello_world777]

Interesting, but he talks way too fast!!

[@dafl00]

Digging and yanking on it without proper grounding... Uuuuggghhhhh You may be better off keeping it in a vacuum sealed box.

[@PeterWalkerHP16c]

+dafl00 TTL probably, tough stuff.

[@grn1]

@@PeterWalkerHP16c Did they even have CMOS at the time, just looked apparently they did. As far as I can tell it did use TTL though so, probably not too much to worry about (TTL is what you often start with when learning to build electronics because while it's not as efficient as CMOS it can take a lot more abuse).

[@PeterWalkerHP16c]

@@grn1 I don't think there were too many CMOS chips if any. The were 74LS / 74HC TTL as far as I can see

[@grn1]

@@PeterWalkerHP16c My search revealed that CMOS had been invented in 69 I think (not bothering to look it up again) but not how common it was.

[@PeterWalkerHP16c]

@@grn1 Doesn't matter when they came out. I've seen the circuit boards.

[@realraven2000]

1111 binary? so you only paid 15Dollars :)

[@Slithy]

Realraven2000 I think he said "eleven thousand". So it would be 11111, or a grand total of 31 dollars :D

[@Slithy]

A. Z. That doesn't sound right to me. I think "eleven hundred" was a tongue slip.

[@realraven2000]

11 grand for an old computer for realz? These people have too much money...

[@RealCadde]

He's talking too fast at times. Makes it really hard to discern what he is saying.

[@nunyabiznez4408]

what exactly is a "web processor file"? Sorry, but the ol' bullshit sensor went off full blast we I heard that. Having a thing doesn't make one knowledgeable about a thing. P.S. I built an Altair when I was 11, so I am unimpressed with yet another Johnny come lately.

[@ggklncnoifewAsdarp]

"word processor files"

[@ingmarm8858]

"this is my $11000 Altair 8800", "let me show you how ESD will turn it into a pile of worthless silicon" :-(