I still have my Altair 8800 and I was partners with a friend in an IMSAI 8080. I wrote the BIOS to make it work with our eight inch floppy disk drives and the print driver for a parallel interface daisy wheel printer. Every programmer should write some assembly language programs just to experience computing at a very fundamental way.
Built my first Imsai in Winter of '78. It was the PCS8030 with the 8085 3Mhz processor. Got a base 8080 chassis a few months later and modified the front panel to work with the MPU-B. Added a pair of Calcomp 142's with the DIO-B and actually got several MIO's to work. With the VIO-C used it for a few years before I built a Z-80 with a Jade-DD HD controller. When I bought the first one, told myself I was only going to learn enough to do what I needed, then Imsai died and I had to. The Imsai 22 slot backplane was much superior to the Altair because it was MUCH quieter (electrical noise) and the MPU-B's 8085 had data latched on the trailing edge of the ALE signal allowing you to run 3 MHz with 666ns memory (extra clock cycle to get memory data stable). Used CP/M until I eventually went to DOS when it was 3.0. If you want to see the easter egg in Wordmaster, try entering an EOF in the middle of a document by hitting ^P ^Z and the software will respond with 'TURKEY' because you just cut off your document at that point. Still have the unit and most parts and docs unpowered for many years. Really enjoyed the simplicity of the machine once you got over the binary thing. I actually labeled the toggle switches 8 4 2 1 to help familiarize myself with the conversion. It's amazing how many useless and obscure deatails you can remember after 35+ years.
Still have mine! Actually it's a Fulcrum clone of an IMSAI, but it does have a Z80A CPU and hard drive controller. Taught myself a lot with that machine.
Just made one of these to add to my retro collection - although it's not really retro. Took about 3 hours to build and now I'm having loads of fun. Awesome cheap fun!
So cool. I recall looking at the IMSAI 8080 back in ghe 70s with a good deal of envy. Out of my price range back then. I'm going to follow up and get more information. Thanks for sharing this...!
Bit of a late comment, but the Altair 8800 was actually the first 8080 computer available in kit form in 1975. IMSAI came second. The primary difference is that the Altair front panel subdivided the toggle switches/LEDs into groups of 3 to designate "Split Octal", where a byte was represented as 76 543 210, or 377 if all the bits were 1s. This was the common number base used by mainframes and mini-compters at the time. The IMSAI was the first to subdivide the toggle switches/LEDs into groups of 4 to designate "Hexadecimal", the up-and-coming replacement for split octal, as it allowed all bit groupings to be identical. Bytes were split into 2 groups of 4... 7654 3210, or FF if all the bits were 1s.
This was great! I remember seeing this 1st in Popular Electronics back in the day. I was a 15 year old kid that had just finished a radio broadcasting class and had my 3rd class Radio FCC license for broadcasting. I wanted one so bad but my Mom had the school bill to pay. So I could only look at it in the magazines of the time. By my 17th birthday I had saved enough to get a Timex Sinclair from Radio Shack. I did the usually basic programing but I did not like the logic of basic. So I just loaded programs from the computer magazines of the day. The UK had the best computer mags when it came to the Sinclair.
....I botched my first Altair 8800 in 1976 at 13 years old, but shortly after getting my Novice Ham license in 1977 I built my first IMSAI 8080. I want back and completed the Altair a couple of months later but the IMSAI was definitely better. It was amazing at the time but in retrospect I can completely comprehend how they felt in the stone ages.
Great video Mick! What Dave have done is very impressive, not only the hardware side, also the software side. The web interface is looking stunning and he also use websockets (close to real-time)! Thumbs up! Recently I saw a video "EEVblog #1232 - Add Web Access To Old Instruments!" and despite the effort, it is not that great (clunky) because it is using polling instead, not websockets. The product of Dave seems to be very well made and using all kind of modern webtech to get maximum experience. Allot of effort, he must be a perfectionist. Amazing! Any idea how much the unit will costs because it is not mentioned on the website.
I stated with an Altair 8800 was SerNo 33. But liked to appearance of the IMSAI better and it had a full S100 mother board while Altair had to join 4 slot segments. Power supply on IMSAI also was better. STILL HAVE THE IMSAI TODAY! Have not run it for many years now, but have MANY S100 Cards. Built own Harddrive interface and wrote Bios , formatting, partitioning software. Mainly ended up with much Cromemco hardware.
I had a 8080 running 4 a/d, timing, 4 pnuematics and 16 vibratory mechanisms. It was slow. It was 1 megahertz. I went a overclocked it 1.25 and just was able to keep up. I thought that I put in a 8047 board running 4.77 megahertz that It would fine, but 4.77 /4 = 1.19 and 1.25 on the 8080 a lot more. Counting instructions.
And mine was with Intel 8080 based computer (Intelec(?) 8080, Serial #0000000014) in 1977 or 1978. RMIT Physics dept. ordered the Intel 8008 computer but switched order to 8080 as soon as it became available. It too had rows of switches and leds and had to be manually programmed to execute a jump to eprom monitor, via a 3 byte instruction at address 0x0. A reset would get things going. Once in eprom monitor, it was possible to execute OS boot function to load OS from 8" floppy drive.
@@MickMake It was never an inexpensive computer to make when it first came out because of the quality of materials and construction. Truly industrial grade throughout.
It is tempting to order one of these but I'm holding off due to lack of information about the price range on the web site. I don't know if it will be $100 or so or closer to $1000. There is an Altair 8800 replica that runs about $600. I was tempted by it but at that price point I've held off getting it. I'm sure both the 8800 and 8080 replicas are still cheaper than the real vintage 8800 I saw at a market where the owner wanted $4000 for it.
A critical moment in my 46 year career as a mainframe programmer (1966-2012) was sitting at the console of an IBM 7094 mainframe and entering and running a small program through the console switches. That's when the lightbulb went on. en.m.wikipedia.org/wiki/IBM_7090#IBM_7094
I see you making pcbs etc. Have you ever had boards completely built, parts soldered on? I have a project with strong potential to sell but not to DIYers.
I still think the Altair-Duino 8800 (Altair 8800 Clone) is an more authentic 8800 experience. I have my Altair Duino 8800 connected directly to a DEC VT terminal. The IMSAI 8080 replica is interesting but I still like the Altair 8800 Clone more, as the source code is open (thanks to David Hansel Opensource Software and Hardware) and their are lots of great resources & kits available from Adwater & Stir and Mike Douglas.
@@MickMake The porting Z80pack work? I think David Hansel's open source software and hardware s still a much more impressive and open project . github.com/dhansel/Altair8800 Hardware www.hackster.io/david-hansel/arduino-altair-8800-simulator-3594a6
A long time ago I had a SWTPC 6809 system running with 2 x 8 inch and 2 x 5.25 inch floppies. I really wish I still had it, despite the fact it was incredibly unreliable (mostly the floppy controllers). Actually, now I think about it that is probably why it was given to me! :)
wargames ..love it .. however in movie its very unlikely he could have afforded such a machine as it was a massive expensive in day around $931 dollars = $4,824.62 in 2022 just for the base unit alone
Used to have a "real" one in the '90... But I really preferred my HP3000 which took most of my basement ! www.hpmuseum.net/images/3000-II_1977-PromoPhoto-27.jpg
You never know. I can't remember off hand the specs of the S-100 bus, but it might be doable with maybe an I2C S-100 converter. Would be a custom jobbie. Later in the year, I might investigate this, (once my other projects are done).
I still have my Altair 8800 and I was partners with a friend in an IMSAI 8080. I wrote the BIOS to make it work with our eight inch floppy disk drives and the print driver for a parallel interface daisy wheel printer. Every programmer should write some assembly language programs just to experience computing at a very fundamental way.
Built my first Imsai in Winter of '78. It was the PCS8030 with the 8085 3Mhz processor. Got a base 8080 chassis a few months later and modified the front panel to work with the MPU-B. Added a pair of Calcomp 142's with the DIO-B and actually got several MIO's to work. With the VIO-C used it for a few years before I built a Z-80 with a Jade-DD HD controller. When I bought the first one, told myself I was only going to learn enough to do what I needed, then Imsai died and I had to. The Imsai 22 slot backplane was much superior to the Altair because it was MUCH quieter (electrical noise) and the MPU-B's 8085 had data latched on the trailing edge of the ALE signal allowing you to run 3 MHz with 666ns memory (extra clock cycle to get memory data stable). Used CP/M until I eventually went to DOS when it was 3.0. If you want to see the easter egg in Wordmaster, try entering an EOF in the middle of a document by hitting ^P ^Z and the software will respond with 'TURKEY' because you just cut off your document at that point. Still have the unit and most parts and docs unpowered for many years. Really enjoyed the simplicity of the machine once you got over the binary thing. I actually labeled the toggle switches 8 4 2 1 to help familiarize myself with the conversion. It's amazing how many useless and obscure deatails you can remember after 35+ years.
Still have mine! Actually it's a Fulcrum clone of an IMSAI, but it does have a Z80A CPU and hard drive controller. Taught myself a lot with that machine.
Just made one of these to add to my retro collection - although it's not really retro. Took about 3 hours to build and now I'm having loads of fun. Awesome cheap fun!
I always liked the Imsai front panel over the Altair. Those paddle switches are much nicer than plain old toggles.
So cool. I recall looking at the IMSAI 8080 back in ghe 70s with a good deal of envy. Out of my price range back then. I'm going to follow up and get more information. Thanks for sharing this...!
No probs, mate.
Bit of a late comment, but the Altair 8800 was actually the first 8080 computer available in kit form in 1975. IMSAI came second. The primary difference is that the Altair front panel subdivided the toggle switches/LEDs into groups of 3 to designate "Split Octal", where a byte was represented as 76 543 210, or 377 if all the bits were 1s. This was the common number base used by mainframes and mini-compters at the time.
The IMSAI was the first to subdivide the toggle switches/LEDs into groups of 4 to designate "Hexadecimal", the up-and-coming replacement for split octal, as it allowed all bit groupings to be identical. Bytes were split into 2 groups of 4... 7654 3210, or FF if all the bits were 1s.
Built two, one for a friend and one for me. Both working great. Really liking this.
This was great! I remember seeing this 1st in Popular Electronics back in the day. I was a 15 year old kid that had just finished a radio broadcasting class and had my 3rd class Radio FCC license for broadcasting. I wanted one so bad but my Mom had the school bill to pay. So I could only look at it in the magazines of the time. By my 17th birthday I had saved enough to get a Timex Sinclair from Radio Shack. I did the usually basic programing but I did not like the logic of basic. So I just loaded programs from the computer magazines of the day. The UK had the best computer mags when it came to the Sinclair.
....I botched my first Altair 8800 in 1976 at 13 years old, but shortly after getting my Novice Ham license in 1977 I built my first IMSAI 8080. I want back and completed the Altair a couple of months later but the IMSAI was definitely better. It was amazing at the time but in retrospect I can completely comprehend how they felt in the stone ages.
A+. You know you're a nerd when seeing that switch panel makes the front of your trousers tighten a bit.
You are DEFINITELY using those switches wrong.
So women can't be nurds? what gender centric nonsense is this..
Flux fixes everything from chunky soldering iron bits to existential angst.
I played Star Trek on an Altair 8800. It was like living in the future for child of the 70's
Oh yeah. Those were the days.
I had an IMSAI 8080 but eventually got rid of it. How I wish I had held on to it. It would be quite a collector's item today!
There was a Z80 board available for the IMSAI 8080 that really cracked it up.
Awesome to watch & re-live this build again 20 months later.
Mick was so incredibly annoying that day! :)
It does the Z80! The Z80! The Z80! Sweet! I need to get one.
I’m interested in details how exactly imsai front panel works
Great video Mick! What Dave have done is very impressive, not only the hardware side, also the software side. The web interface is looking stunning and he also use websockets (close to real-time)! Thumbs up! Recently I saw a video "EEVblog #1232 - Add Web Access To Old Instruments!" and despite the effort, it is not that great (clunky) because it is using polling instead, not websockets. The product of Dave seems to be very well made and using all kind of modern webtech to get maximum experience. Allot of effort, he must be a perfectionist. Amazing! Any idea how much the unit will costs because it is not mentioned on the website.
Where are you mick?
I stated with an Altair 8800 was SerNo 33. But liked to appearance of the IMSAI better and it had a full S100 mother board while Altair had to join 4 slot segments. Power supply on IMSAI also was better. STILL HAVE THE IMSAI TODAY! Have not run it for many years now, but have MANY S100 Cards. Built own Harddrive interface and wrote Bios , formatting, partitioning software. Mainly ended up with much Cromemco hardware.
I had a 8080 running 4 a/d, timing, 4 pnuematics and 16 vibratory mechanisms. It was slow. It was 1 megahertz. I went a overclocked it 1.25 and just was able to keep up. I thought that I put in a 8047 board running 4.77 megahertz that It would fine, but 4.77 /4 = 1.19 and 1.25 on the 8080 a lot more. Counting instructions.
My first introduction to computers was an IMSAI 8080 back in early 80's.
What an intro!
And mine was with Intel 8080 based computer (Intelec(?) 8080, Serial #0000000014) in 1977 or 1978. RMIT Physics dept. ordered the Intel 8008 computer but switched order to 8080 as soon as it became available. It too had rows of switches and leds and had to be manually programmed to execute a jump to eprom monitor, via a 3 byte instruction at address 0x0. A reset would get things going. Once in eprom monitor, it was possible to execute OS boot function to load OS from 8" floppy drive.
Love it! Awesome !
An IMSAI just sold on EBay for $1925. Also there is one sitting on the shelf if you watch the comedy series The IT Crowd.
Yeah amazing how retro kit ends up being just as expensive years later as the day it came out
@@MickMake It was never an inexpensive computer to make when it first came out because of the quality of materials and construction. Truly industrial grade throughout.
I miss CP/M 2.2
I haven't PIP'd anything in years....
I haven't pip'd since I had my Morrow Micro Decision.
It's the reverse of what we do today. pip [where it's going to] [where it's coming from]
1. Can you 'import' your own floppies?
2. How true is the panel display to the original? ( in terms of activity, not the physical panel)
Soundtrack straight from Starsky 'n Hutch?
Your computer called me !!!!
David, machines don't call people.
You have to remove the G+ in the intro soon
Thanks for sharing this vintage computer :-)
Yeah, I think it's time for a refresh!
Vintage sharing for a vintage computer?
Was that Kath Day-Knight?
It is tempting to order one of these but I'm holding off due to lack of information about the price range on the web site. I don't know if it will be $100 or so or closer to $1000. There is an Altair 8800 replica that runs about $600. I was tempted by it but at that price point I've held off getting it. I'm sure both the 8800 and 8080 replicas are still cheaper than the real vintage 8800 I saw at a market where the owner wanted $4000 for it.
You might prefer the altair-duino, a cheaper replica that looks really nice. I have one and really enjoy it. www.adwaterandstir.com/altair/
I read on the forum it was $250.
@@avt3216 Thank you for the information. That's a decent price. It is very tempting to buy one.
Poor Kean! Great video though!
A critical moment in my 46 year career as a mainframe programmer (1966-2012) was sitting at the console of an IBM 7094 mainframe and entering and running a small program through the console switches. That's when the lightbulb went on.
en.m.wikipedia.org/wiki/IBM_7090#IBM_7094
I see you making pcbs etc. Have you ever had boards completely built, parts soldered on? I have a project with strong potential to sell but not to DIYers.
Yes indeedy. However I can’t really take on any more projects. I’m flat to the boards at the moment.
Thank You!
hey Mick we miss you. Hope all is well.
I still think the Altair-Duino 8800 (Altair 8800 Clone) is an more authentic 8800 experience. I have my Altair Duino 8800 connected directly to a DEC VT terminal. The IMSAI 8080 replica is interesting but I still like the Altair 8800 Clone more, as the source code is open (thanks to David Hansel Opensource Software and Hardware) and their are lots of great resources & kits available from Adwater & Stir and Mike Douglas.
Dave McNaughton has open sourced his code and has actually contributed a lot.
@@MickMake The porting Z80pack work? I think David Hansel's open source software and hardware s still a much more impressive and open project . github.com/dhansel/Altair8800 Hardware www.hackster.io/david-hansel/arduino-altair-8800-simulator-3594a6
Are we there yet? No! Are we there yet? No! Poor guy! ;)
where are ya Mick?
Awesomeness!
Where is MickMake?
👍👍👍
YOu back soon?
No, REALLY, how much? We can't decide whether to be interested without a ballpark. $50? $500? Makes or breaks it for a novelty.
I own an original dual floppy 8 inch floppy system
Oh nice!
A long time ago I had a SWTPC 6809 system running with 2 x 8 inch and 2 x 5.25 inch floppies. I really wish I still had it, despite the fact it was incredibly unreliable (mostly the floppy controllers). Actually, now I think about it that is probably why it was given to me! :)
Kean Maizels a friend of mine still has his: www.obsoletecomputermuseum.org/swt/
wargames ..love it .. however in movie its very unlikely he could have afforded such a machine as it was a massive expensive in day around $931 dollars = $4,824.62 in 2022 just for the base unit alone
Mick you don't look old enough to have been in the 70s.
Ho-Hum!!!
Used to have a "real" one in the '90... But I really preferred my HP3000 which took most of my basement !
www.hpmuseum.net/images/3000-II_1977-PromoPhoto-27.jpg
Yeeeeee
""Shall we play a game?""
Thanks Mick. Great video. I forgive you for being such a pest :D
nice
But can it play Doom?
It's no fun if you can't put your own cards in it.
You should suggest it to Dave!
@@MickMake that'd increase the kit's cost too much, I presume.
You never know. I can't remember off hand the specs of the S-100 bus, but it might be doable with maybe an I2C S-100 converter. Would be a custom jobbie.
Later in the year, I might investigate this, (once my other projects are done).
Still lots of fun, but I know what you mean. I still have my heavily modified VIC-20 from the early 80's.
DOOD!