Thanks for bringing back good memories! I remember the IMSAI 8080 with the operator panel my dad built one from a kit in early 1977 he got from The Byte Shop. He ordered his kit with the Zilog Z80 option, direct connected keyboard and interface card, 16K memory card, a cassette card, an I/O card. After a year he brought home a Micropolis 1053-2 dual disk drive with card and a Dazzler graphics card. The first "monitor" was a B&W 13" TV he modified for use with a composite signal (until he got a color TV after the Dazzler was installed). The boot sequence for the tape was the only thing I remember doing before the disk drive. Far left four blue switches-UP, 1st red switch DN, and second red UP then pull the RUN/STOP switch UP and it would load from a cassette recorder. I played a version of the Star Trek game on that computer that opened up with Admiral Fox greeting the player. Can't remember which version of the game it was and have tried to find it but haven't been able to. I played it for years until I discovered the world of BBS's after getting a Commodore 64 with the Datasette and Vic Modem for Christmas 1983. Yes. Good memories indeed! Thank you!
I worked in highschool and later college for a small startup in Colorado that had an IMSAI 8080. They did some amazing things with that computer before finally moving their development over to apple 2s. They had everything from editors and compilers to paper tape readers/writers along with other storage and video output peripherals. I think their first assembler for 6502 on Apple2 was from this IMSAI. Good memories.
Always excellent, thank you. FWLIW: On the subject of surface mount soldering from one person who doesn't do a lot to another. The 'trick' is while through-hole needs accurate soldering rather than component placement, surface mount is all about accurate placement while not giving a damn about the soldering... use a crap-ton of liquid flux, tack the corners, drag a seemingly stupid amount of solder over the pins and pads, then drag a clean iron (+/- good wick) to mop up the excess, adding more flux if the pads aren't still swimming. Repeat until all the bridges are gone! PS: Hot air is another technique again that also takes a surprising lack of care as long as there's plenty of flux on hand. This time flux, solder, flux the pads, place-ish the component, more flux if not swimming, hot air... and assuming you didn't blow the component away with too much air flow you'll know when it's done because the component will 'jump' in to alignment for you. Check for bridges and remove any with the tip of a clean iron. (flux!) ...most people who teach these techniques are pretty good at it so understandably get away with less than desirable amounts of flux (and solder) because that's quicker and less expensive. For the occasional solderer it's best to go ham with the flux, use more solder than you think is sensible, mop up the excess, and not cry about the time or waste.
I’ll +1 on that hot air technique, I was horrid at surface mount, which made me more terrified of it. I picked up a hot air station, some decent paste, and 6 SMD teaching kits. I’m better at it now, and by “better” I mean “suck a lot less”.
I do need to buy a hot air station it would probably make life easier. Its just making my self spend money on a thing I don't like is challenging when friends keep pointing out all the retro machine that are on sale that they know I want🤣
Part 2 (comments re War Games from an IMSAI owner)... If you look closely, you will notice all the LED's on the machine are always lit. This results from the fact that there's no CPU card in the machine. When phoning, he puts his telephone in an acoustic coupler (300 baud max), has a box labeled IMSAI 212 (1200 baud max and never built) and then gets data at what appears to be 9600 baud. Either Todd Fisher or Nancy Fieitas (excuse spelling) who provided the IMSAI stuff apparantly insisted that they use two hands to close the doors on the CalComp drives... If you just push down on one side you tend to break the door...
'70s computers with rocker switches are the coolest thing ever - which is a striking contrast to '70s electric organs with rocker switches. Those just remind me of being bored out of my mind at my grandma's house in the scorpion-infested outskirts of northern Tampa while my grandpa tried to play church music on his 1981 Omnichord, occasionally pausing to tell me to stop horsing around.
I came into the hobbyist market one generation after the IMSAI. That machine just looked cool. The 8080 and Z80 were fast for simple text. I used mine all the way thru law school and it gave me an edge over the other students. Wow, nostalgia.
Brings back memories. Bought one as soon as they were available back in the day. The old S100 bus (I guess more of an 8080 bus, to be exact) cards were big and not too crowded so soldering wasn't that big a deal. Got tired of keying in programs on the front panel so built a point to point wired ASKII keyboard and initially used an old Type 33 teletype as the output. Eventually added a couple of terminals and 8 inch drives I salvaged from somewhere. Great memories. Mine never talked like the one in War Games, but then the IMSAI was obsolete by the time War Games came out, anyway.
Really cool! This was the Cadillac kit, as we built the 8008 based unit published in Radio Electronics. With existing experience in broadcast automation systems using huge wire wrapped shift register memory boards, it wasn't too bad to construct. I had a friend that was a salesman for Shafer Electronics, so free mfg. reference manuals were available. Back then, these books had the complete instruction set in the appendix. Later on, I found myself working on the first American made audio mastering consoles from MCI (later bought by Sony) with motorized moving faders, using the famous Z80 as the programmable controller. As engineers, we preferred the Motorola 6800 CPUs, as they were more UNIX friendly. Apple adopted the 6800 for the Apple II, and I worked for a local shop called, "Computers and Things" that was an independent and the first Apple dealer in Austin. What an era!
I remember building several of these back when I was a computer science major at Sac State in the late seventies. We added an improvement to the S100 mother board to add termination resistors to each trace close to the ground end to suppress noise.
The Royal Mail thing reminds me a phone conversation I had with them. RM "You have been calling this office every Wednesday for last 5 months asking if there's anything for you" ME "Unless you leave a card or something, there is no way of knowing" RM "The postman leaves a card when no answer" ME "But you need to leave a card, otherwise I won't know" RM "The postman leaves a card when no answer" ME "Unless you actually LEAVE this card there's no way of knowing you've been" RM "The postman leaves a card....
I’ve had this conversation a bunch, having to explain that if they didn’t find the right doorbell and therefore the tight building lobby they couldn’t possibly leave a card for me to see. And if they could leave a card, they could also just leave the parcel by the door.
@@kaitlyn__LI once had this with UPS who sent me a postcard(!) telling me they couldn't deliver my parcel because my address was "invalid". Of course they sent said postcard to the very same "invalid" address which, as you might have guessed, wasn't so invalid after all.
Outstanding video! I got into computing in 1977 (the year of Star Wars) with the Radio Shack TRS-80; which would later be called the Model I, just as Star Wars would come to be called Episode 4, A New Hope. (Don't get me started!) My model had a 4K, Tiny BASIC on ROM, 4K of RAM, and a monochrome all-uppercase monitor and a cassette interface. I mention all this because we early computer hobbyists were aware of the Altair, IMSAI and Northstar systems, but didn't know much about them because we all had our own different Users Groups to go to. Which is why I'm so happy to find this video with such a nice explanation of the IMSAI. All good wishes.
Yup, Commodore, Atari, TI, Tandy, Sinclair, Apple, and probably missing a few, all separate groups back in the day. Once the IBM PC clones really took off, most of the others started to die off.
Thanks for making this! You have to remember the computer on Wargames was probably upgraded to a Z80 if “David” was a real hacker :) ..and he probably got it cheap considering how outdated it was by 1984. Fun fact: The WOPR prop was an Apple II!
I’ve always wondered if he got it for Xmas several years before the events in the movie take place. It then makes me wonder, if that’s the case, what does his dad do for a living.
The IMSAI was already obsolescent by the time WarGames came out, I had an Atari 800 when I saw the movie and most of my rich friends had an Apple II. David Lightman the super hacker wouldn't have been using one of these in 1983, not with the kind of money his parents had lol Hollywood always gets stuff like this wrong
I think it's because at the time Hollywood thought all computers were mysterious boxes with random lights that blink out of sequence on them and a real early 80's PC doesn't look like that, it looks like a C-64 or something, a keyboard plugged into a monitor and peripherals. Look at WOPR, it's a classic Star Trek computer with lots of meaningless lights blinking out of sequence all over it. The IMSAI fits this bill very well. Could you have even used an IMSAI to log on to an old school bulletin board system? Download things with Xmodem? Did it even have a disk drive? The Atari 400 came out in 1979 and it was ALREADY more powerful than an IMSAI lol
I built one of these High Nibble kits a couple of years ago. It sure plays a mean game of chess. The quality of the kit is outstanding, with incredible attention to detail and is only bettered by the quality of the emulation software. Be aware that the way the clear Perspex back panel is held in the metal cover can result in the Perspex cracking and breaking off around the nut fixings (ask me how I know?). The solution is to superglue the four mysterious white Perspex reinforcements shown in the top left of the video at 11:56 to the clear Perspex back around the nuts. The reinforcement with the one corner missing goes in the corner beside the ESP32. It's obvious when you try it :-)
I built one of these kits too, they are extremely well made. The only weakness is as you mentioned, mounting the back panel to the frame. After I cracked mine too, a little 3d printing later and I have a solid mount. Highly recommend the 3d printed mount as it's hidden and much stronger than the acrylic. I think this is really the only weakness of this kit.
@@kaitlyn__LExtra fun when it's been exposed to sunlight for years and years. I was once hoping I could restore an early 3D printer. Nope, all the plastic parts fell apart in my hands.
I like that name “High Nibble” ... and his slogan, “For The More Significant Bits”. Obviously nothing to do with anything you might nibble to get high ...
My first computer ran on the S-100 bus. It was a North Star Horizon, dual floppy with an extravagant 16Kb of RAM. It ran North Start DOS. This computer did real work for sales invoices and inventory, using a Hazeltine 1520 in our family business. Later upgraded it up to 64Kb so as to run CP/M. Early days! Thanks for the video.
Thanks for the fond memories. I actually have an IMSAI 8080 system that I built in 1977. One day I will look at refurbishing it (hasn't been powered up in about 40 years). I will probably want to clean up the silver-plated chip leads that have turned black as well as replace the ginormous electrolytic capacitors in the power supply.
This brings back memories. An IMSAI 8080 was the first micro I ever worked with. I was at Hughes Research Labs at the time, at the tail end of the 70s. We had a tricked-out 8080 with dual floppies and a whole 16k of static RAM that ran an automated test setup another guy and myself put together. I’m hazy on the details, but think we used an IEEE-488 card in it to control a couple of digital multimeters and an X-Y probing station. I programmed it in Microsoft Basic under CP/M. Good times :-)
Hey, One I know very little about. Although back in the mid-2000s, because of the movie Pirates of the Silicon Valley (which desperately needs a remake with history beyond 1999), I figured this or an Altair would probably be the first switch computer I ever got my hands on. Nope, PiDP-11. And I ended up playing with a PDP-1 simulator before that. 😅 12:00 Easier method of Surface Mount Soldering (which is my favourite BTW): Tack the corners, Loads of solder, don't worry if you make shorts, cover all pads and legs, everything completely coated now?, lay solder braid across all the joints on an edge, sweep your iron across the braid, raise the braid and be amazed at your factory looking SMD job, repeat across other edges. I used to hate Surface Mount Soldering until I saw one of Benjamin J. Heckendorn's tutorials on the subject. He made it extremely easy, and made me realise I was overcomplicating the job by trying to be too careful.
If you get solder paste in one of those dispenser syringes it allows you to put both solder and flux on the pad before applying heat, so you don't have to mess around with solder wire. It kinda works with an iron but it leaves many of the solder balls unmelted and floating around and you have to wash them off with isopropyl. Works much better with hot air and/or a hotplate. If I'm being lazy I will put paste on the pads and then hit like 4 legs at once(on an SOIC-8) with a 6mm chisel solder tip. If you're going to use wire the most important thing is to get the half size wire! I don't know the exact measurement of it I think the normal wire like you have is 1mm and this stuff is like 0.5mm The technique I used before that was like yours, put some solder down on one of the pads, clean and put flux on it and one end of the component, then with tweezers and the iron attach the component to that one soldered pad. Then for the other pads, lay the end of the wire down in the joint you want to solder and hit it with the iron. This limits the amount of solder to just that which is in the joint initially and you don't have to try to feed in a tiny amount of wire from the side. At this point I dread through hole component much more because there's all the fiddling around with cutting the leads and they're a pain to clean all the burnt flux off of. Surface mount is quick and clean.
The IMSAI 8080 and the Polymorphics 88 (Poly 88) were what I learned BASIC programming on. The IMSAI took a few entries on the paddle switches to get the monitor code running, before we could work on actual programming.
Great vid! Really interesting to me, as friends of my parents setup a computing shop in Epsom, Surrey, UK as an IMSAI dealership. They ploughed all of their savings into it and opened, after many teething problems. A week later IMSAI went bust… That was the end of that, really. They had to relocate to Yorkshire and start life over. I’m sure there are many other similarly sad tales.
I don't know if it's the cadence, the accent or the Royal Mail rant, but this video has the best (and possibly longest) Alan Partridge impression I've ever heard. AAA++++ would watch again
FUN fact. I ordered this exact same kit. and I politely asked the creator of the kit to solder the surface mount parts as I have a tremor in my hand, and he obliged :) Its in the mail right now :) some heroes don't need capes.
Dave is the nicest guy, after I made this video he came over to the UK for retrofest in Cambridge. So I got to spend many a happy hour chatting to him while we drank a number of warm beers. Hopfully he'll get to come over again at some point.
Never thought I would see SMD inside an IMSAI! Imagine telling the creator that one day his machine would contain, and be emulated by a 32 bit microcontroller the size of a matchbox. Let alone - it has a web interface without the need of a modem! He would **not** have believed you. Great video BTW :-)
@@RetroBytesUK Yes, its mindboggling, compared to what we had to do in the 70's/80's to get embedded stuff going. Looking at the new Teensy's for example. Incredible.
My first computer was an IMSAI 8080, i bought in kit from from Byte Shop in June 1975, I had only 24K of RAM, and a few cards, one of which was a Cromemco Bytesaver 2708 eprom programmer in which I burned a copy of Processor Technology's BASIC, I had the Processor Tech VDM-1 video card and their cassette interface (1200 baud). I had to install a line choke on the AC line because my computer would reboot every time the refrigerator came on
Our UYK-7 system could boot form reel-to-reel tape, which would then utilize Winchester disks, but we still had to manually enter the initialization code via the main console switches. I think I only had to do it once (technically twice because I screwed up the first attempt, which was common). Eventually I became the “micro computer guy” and never had to deal with that antiquated POS again. FYI: Troubleshooting the tape drives was a nightmare. I don’t think we ever had more than two of three functional at any given time.
Even the "real" IMSAI 8080 and the "real" Altair 8800 still had fake front panels. Those CPU chips didn't have enough pins to directly have the front panel lights and switches connected. What happened was that the "front panel" actually consisted of a ROM chip with tiny programs that input/output the front panel switches/lights to the CPU via the regular input/output lines. Nothing like the original PDP-8 etc, - especially the PDP-12 which was a GORGEOUS thing! - where the front panel switches and lights were directly connected to the circuits.
lol, surface mount is easier than through hole, it just takes a little practice with the right iron tip. A J tip is mandatory imo. It’s shocking how much difference it makes. PS great video, I have a High Nibble IMSAI 8080. It’s amazing.
surface mount stuff is so tiny though. very hard to not accidentally short things. also surface mount just sucks. I'm a systemelectronic engineer and i work in maintenance in a company producing cables. and fairly often some part of a machine will just randomly not work anymore at random amounts of time. its newer machines that have more problems compared to some old stuff from like the 70s and 80s.
11:09 I can relate to that, I sometimes get calls from delivery people where they say nothing on my answering machine, they apparently can't read my intercom listing for my name, input four digit codes, or leave notice they had been there. It's either that or I've been home all day and I get a message "they just missed me".😒 It's interesting to see what home computing was like for before PCs, in that era you really had to be dedicated to computing and search out materials intensely, kind of reminds me of the early days of video exports or playing Japanese games before emulation Ie. full time job to get a hold of anything.
I worked and even Ran the Company named UltraByte, back in 76 -78 and we sold over 2000 of these IMSAI 8080's. Even 20 to NASA. Basic was the simple language.
@@RetroBytesUK I did a gcse computer science project on if computers or humans were able to provide better random numbers. By looking at the distribution and the mean I could determine that computer random numbers were better than a person, but groups of people were better than computers. Oddly but not included in my final results was that random numbers generated in sc2 under cpm on a z80 were significantly more random than numbers generated by sc2 under ms dos on an 8088. I never got to the reasoning why. But it was very repeatable
The IMSI HAD a memory mapped IO card called the VIO , it had 2 k of video ram and 2 k rom with a terminal emulator and a cpu monitor with memory read and write etc. also had an serial IMSI smart keyboard with programible keys. I just added a parallel dum keyboard unstead. word star intagrated with it and it was fast.....
When I was a kid, I strolled by the local electronics store to stare at the IMSAIs. ALTAIRs and SWTP computers of the day and imagine myself building my first S100 computer. It was probably fortunate that my first computer was an apple ][+; anything I built without any experience would likely have never worked.
As someone who built a Heathkit H8 in 7th grade (took a weekend), you just earned a like & sub. Don’t know how this ended up in my recommended video list, but thank you UA-cam!
"MITS", not "MIT", for Micro Instrumentation and Telemetry Systems; they got their start making those two kinds of electronics for hobby rocketry and similar small missiles, then went into early calculator before producing the Altair 8800.
The easiest way to solder smd chips is to just solder 2 pins on opposite corners then drag the solder and iron across all pins it will bridge some thats ok then use solder wick and suck up the extra and the solder on bridged pins this method looks great and haven't ever had a bad solder joint
There's something quick to try that might fix the vertical hold sync issue on your vt220. Take the case off and look on the lower right or left side for two turn-pots. One is the vertical hold, and it's worth a try to turn it back and forth a few times to clean the contact. This might fix it..
You mentioned the 4004. Well, I was disassembling a huge number of PC boards, and sorted the chips to be sold later. I had a number of chips I wasn't familiar with. Among them was an Intel 4040. I looked up the number, and couldn't believe what I had. I was a bit frustrated because I wanted to know what board it came from to see the support chips if any, and what it did. None the less, it is worth over $100.
OK, now I'm curious how much allowance a teenager in 1983 would have to have to afford all the components of his computer. The computer was sold 1975 to 1979, but there couldn't have been that much of a price decay, right? Even if we assume he got it used from someone picking up something new and fancy, it seems way out of his budget. Or did prices fall off that hard after everyone moved on?
To put the machine into context, David Lightman grew up as an only child in an upper middle class family. And that family was in bicycle range of Microsoft's headquarters, and Lightman had friends at Microsoft. Lightman's socioeconomic status is confirmed by seeing both parents with good paying careers, and a family home which had en suite bathrooms, well in 1983 that was hardly a normal feature in family homes at the time.
You're talking about a last generation computer in a rapidly evolving market. In 1983 you could buy a Commodore 64 for $300 USD, the IMSAI 8080 was $400 USD new in 1976. So the IMSAI in 1983 was 7 years old, pretty old for computer. $400 USD in 1983 is worth the same as $1200USD in 2023 . So it would be within reach for a teenager, especially one with rich parents. But those twin 8" floppy drives would have been crazy expensive, a cassette tape interface would have been more 'in budget'. While the IMSAI is iconic in this movie, I would have thought the C-64 would have been much more the tool of the 80's hacker, and much more likely to be owned by a teenager, you know, color graphics and games.
That’s so funny (or my cell phone is listening at me). I literally watched it yesterday evening again! After hunting for an IMSAI is the price. And even the kit is pricey but I may sway for that.
@@RetroBytesUK I noticed! I was browsing eBay yesterday evening most are in the US, so that’s completely out of the question with me residing in the The Netherland. I saw one in the UK, the prices in your place are even worse than the US prices. So I settled for watching WarGames instead 🤣But this kit is really nice also not cheap at woeien 270 euros but still better than 2400 quid or 2100 dollars. And both of without diskdrive!
There's a thumb-wheel trimpot near the edge of the main board in a VT220 that, when it gets dirty over time, can cause that sort of vsync issue. You may just have to gently tweak it.
@RetroBytesUK on my vt220 all i had to do was tap it sharply with my finger. But i think i then cleaned it and readjusted it anyway. I found the solution in a very old comp.terminals posting
11:30 - One superiority US mail has over UK mail. We don't need a card, just our license to walk in and get our missed packages. No fuss, no muss, and if the town is small enough you don't need a license after the first visit.
The unbuilt kit sitting in the corner just begging to be built, its so nice when you finally find the time for it. I have a kim-1 replica kit just sitting there still waiting.
We love War Games because it is Romantic Comic Idyllicism from the 1980s. We don´t love postmodern media, because it is Ironic Comic Sadism or Ironic Tragic scapegoating
How about a video about mainframe computers, not just IBM, but Burrows and all the other mainframe computer manufacturers? As for IBM, how about discussing MVS?
Great… But… The loud vocal music absolutely wrecks your spoken track. Generally, you don’t need music at all, but if you feel like you have to use it, then make it much lower volume instrumental music in the background…
Prepare for pedantic comments about how the 6502 isn’t a 6800 clone because it doesn’t run 6800 machine code. I got plenty of replies saying that, the last time I compared the Z80 to the 6502 in the exact way you did here 😅
@StringerNews1 thanks for proving my point! It all depends on one’s definition of clone; and the 6501 was designed to be a drop-in replacement electrically, specifically conceived in the design phase as “the 6800 but actually affordable”. No one’s claiming it was exactly the same, everyone knew it had fewer registers etc. Being able to plug in the exact same machine code is only one definition, and in practice doesn’t matter much as memory mapping etc can be so different that your code still won’t work on another machine. If you were editing the memory map anyway, it wasn’t that hard in most programs to change the registers or swap to using the stack to work with the 650X. Just because it can’t run the exact code like a Z80 can with 8080 code, doesn’t mean they weren’t both conceived for the same purpose: a cheap alternative for a particular style of CPU. Especially since most Z80 users also relied on Z80-exclusive functionality, so the 8080 code was getting partially rewritten anyway. As far as the chip market is/was concerned, they’re both clones. A computer designer intending to use an 8080 can use the Z80, and same for a computer designer using the 6800. Both can switch plans after the circuit board mask was already made - which is exactly why the lawsuit getting rid of the 6501 occurred and forced those customers to use 6502 with a pinout adapter. BTW thanks for assuming I’m a CPU arch dummy 😘 I just don’t think being so prescriptive is useful. Where most such nerds will go “ackshully it’s NOT a clone” in an adversarial way, people could instead start a more productive conversation about different types of cloning. But I hardly ever see the latter. I considered snarkily asking if that mini essay was proof enough of my knowledge, but then I realised I don’t actually care.
I'm just sittin here wonering how much somebody would charge to finish the surface mount stuff if I bought one. I love retro, I love wargames, but not nearly enough to attempt surface mount!
When the WarGames movie came out in 1983, the portrayed IMSAI was already painfully obsolete. This was intentional by the filmakers, who wanted to show how hacker-savy Matthew Broderick's character was even with old equipment.
For those looking to hear more from Poke (and there are quite a few of you). soundcloud.com/user-455711299
Thanks for bringing back good memories! I remember the IMSAI 8080 with the operator panel my dad built one from a kit in early 1977 he got from The Byte Shop. He ordered his kit with the Zilog Z80 option, direct connected keyboard and interface card, 16K memory card, a cassette card, an I/O card. After a year he brought home a Micropolis 1053-2 dual disk drive with card and a Dazzler graphics card. The first "monitor" was a B&W 13" TV he modified for use with a composite signal (until he got a color TV after the Dazzler was installed). The boot sequence for the tape was the only thing I remember doing before the disk drive. Far left four blue switches-UP, 1st red switch DN, and second red UP then pull the RUN/STOP switch UP and it would load from a cassette recorder.
I played a version of the Star Trek game on that computer that opened up with Admiral Fox greeting the player. Can't remember which version of the game it was and have tried to find it but haven't been able to. I played it for years until I discovered the world of BBS's after getting a Commodore 64 with the Datasette and Vic Modem for Christmas 1983. Yes. Good memories indeed! Thank you!
That was a nice setup your dad put together.
@@RetroBytesUK Thank you.
I worked in highschool and later college for a small startup in Colorado that had an IMSAI 8080. They did some amazing things with that computer before finally moving their development over to apple 2s. They had everything from editors and compilers to paper tape readers/writers along with other storage and video output peripherals. I think their first assembler for 6502 on Apple2 was from this IMSAI. Good memories.
Its quite impressive just how much you could do with one of them, and the extra hardware you could add.
Yesss. In bed sick on a weekend but new RetroBytes makes that okay!
Vaxxed
Hope you feel better soon.
@@Benny_Shill🤦♂️🤦♂️
I hope you’ve recovered. Agreed that our UA-cam favorite channels are comforting when sick.
Same here, but 5 months later 😅
Always excellent, thank you. FWLIW: On the subject of surface mount soldering from one person who doesn't do a lot to another. The 'trick' is while through-hole needs accurate soldering rather than component placement, surface mount is all about accurate placement while not giving a damn about the soldering... use a crap-ton of liquid flux, tack the corners, drag a seemingly stupid amount of solder over the pins and pads, then drag a clean iron (+/- good wick) to mop up the excess, adding more flux if the pads aren't still swimming. Repeat until all the bridges are gone!
PS: Hot air is another technique again that also takes a surprising lack of care as long as there's plenty of flux on hand. This time flux, solder, flux the pads, place-ish the component, more flux if not swimming, hot air... and assuming you didn't blow the component away with too much air flow you'll know when it's done because the component will 'jump' in to alignment for you. Check for bridges and remove any with the tip of a clean iron. (flux!)
...most people who teach these techniques are pretty good at it so understandably get away with less than desirable amounts of flux (and solder) because that's quicker and less expensive. For the occasional solderer it's best to go ham with the flux, use more solder than you think is sensible, mop up the excess, and not cry about the time or waste.
I’ll +1 on that hot air technique, I was horrid at surface mount, which made me more terrified of it. I picked up a hot air station, some decent paste, and 6 SMD teaching kits. I’m better at it now, and by “better” I mean “suck a lot less”.
I do need to buy a hot air station it would probably make life easier. Its just making my self spend money on a thing I don't like is challenging when friends keep pointing out all the retro machine that are on sale that they know I want🤣
Part 2 (comments re War Games from an IMSAI owner)... If you look closely, you will notice all the LED's on the machine are always lit. This results from the fact that there's no CPU card in the machine. When phoning, he puts his telephone in an acoustic coupler (300 baud max), has a box labeled IMSAI 212 (1200 baud max and never built) and then gets data at what appears to be 9600 baud. Either Todd Fisher or Nancy Fieitas (excuse spelling) who provided the IMSAI stuff apparantly insisted that they use two hands to close the doors on the CalComp drives... If you just push down on one side you tend to break the door...
@@GladeSwope The credits list Fisher Freitas as suppliers. They got IMSAI after it folded...
'70s computers with rocker switches are the coolest thing ever - which is a striking contrast to '70s electric organs with rocker switches. Those just remind me of being bored out of my mind at my grandma's house in the scorpion-infested outskirts of northern Tampa while my grandpa tried to play church music on his 1981 Omnichord, occasionally pausing to tell me to stop horsing around.
I came into the hobbyist market one generation after the IMSAI. That machine just looked cool. The 8080 and Z80 were fast for simple text. I used mine all the way thru law school and it gave me an edge over the other students. Wow, nostalgia.
Brings back memories. Bought one as soon as they were available back in the day. The old S100 bus (I guess more of an 8080 bus, to be exact) cards were big and not too crowded so soldering wasn't that big a deal. Got tired of keying in programs on the front panel so built a point to point wired ASKII keyboard and initially used an old Type 33 teletype as the output. Eventually added a couple of terminals and 8 inch drives I salvaged from somewhere. Great memories. Mine never talked like the one in War Games, but then the IMSAI was obsolete by the time War Games came out, anyway.
Really cool! This was the Cadillac kit, as we built the 8008 based unit published in Radio Electronics. With existing experience in broadcast automation systems using huge wire wrapped shift register memory boards, it wasn't too bad to construct. I had a friend that was a salesman for Shafer Electronics, so free mfg. reference manuals were available. Back then, these books had the complete instruction set in the appendix. Later on, I found myself working on the first American made audio mastering consoles from MCI (later bought by Sony) with motorized moving faders, using the famous Z80 as the programmable controller. As engineers, we preferred the Motorola 6800 CPUs, as they were more UNIX friendly. Apple adopted the 6800 for the Apple II, and I worked for a local shop called, "Computers and Things" that was an independent and the first Apple dealer in Austin. What an era!
Unix would never have run on any Motorola chip less than a 68000-family one.
And it wasn’t a Motorola chip that Apple used, it was the rival 6502.
I remember building several of these back when I was a computer science major at Sac State in the late seventies. We added an improvement to the S100 mother board to add termination resistors to each trace close to the ground end to suppress noise.
The Royal Mail thing reminds me a phone conversation I had with them.
RM "You have been calling this office every Wednesday for last 5 months asking if there's anything for you"
ME "Unless you leave a card or something, there is no way of knowing"
RM "The postman leaves a card when no answer"
ME "But you need to leave a card, otherwise I won't know"
RM "The postman leaves a card when no answer"
ME "Unless you actually LEAVE this card there's no way of knowing you've been"
RM "The postman leaves a card....
I’ve had this conversation a bunch, having to explain that if they didn’t find the right doorbell and therefore the tight building lobby they couldn’t possibly leave a card for me to see. And if they could leave a card, they could also just leave the parcel by the door.
@@kaitlyn__LI once had this with UPS who sent me a postcard(!) telling me they couldn't deliver my parcel because my address was "invalid". Of course they sent said postcard to the very same "invalid" address which, as you might have guessed, wasn't so invalid after all.
Outstanding video! I got into computing in 1977 (the year of Star Wars) with the Radio Shack TRS-80; which would later be called the Model I, just as Star Wars would come to be called Episode 4, A New Hope. (Don't get me started!) My model had a 4K, Tiny BASIC on ROM, 4K of RAM, and a monochrome all-uppercase monitor and a cassette interface. I mention all this because we early computer hobbyists were aware of the Altair, IMSAI and Northstar systems, but didn't know much about them because we all had our own different Users Groups to go to. Which is why I'm so happy to find this video with such a nice explanation of the IMSAI. All good wishes.
Yup, Commodore, Atari, TI, Tandy, Sinclair, Apple, and probably missing a few, all separate groups back in the day. Once the IBM PC clones really took off, most of the others started to die off.
Thanks for making this!
You have to remember the computer on Wargames was probably upgraded to a Z80 if “David” was a real hacker :) ..and he probably got it cheap considering how outdated it was by 1984.
Fun fact: The WOPR prop was an Apple II!
I’ve always wondered if he got it for Xmas several years before the events in the movie take place. It then makes me wonder, if that’s the case, what does his dad do for a living.
@@c1ph3rpunkhe probably owns a dog washing business
The IMSAI was already obsolescent by the time WarGames came out, I had an Atari 800 when I saw the movie and most of my rich friends had an Apple II. David Lightman the super hacker wouldn't have been using one of these in 1983, not with the kind of money his parents had lol Hollywood always gets stuff like this wrong
I think it's because at the time Hollywood thought all computers were mysterious boxes with random lights that blink out of sequence on them and a real early 80's PC doesn't look like that, it looks like a C-64 or something, a keyboard plugged into a monitor and peripherals. Look at WOPR, it's a classic Star Trek computer with lots of meaningless lights blinking out of sequence all over it. The IMSAI fits this bill very well. Could you have even used an IMSAI to log on to an old school bulletin board system? Download things with Xmodem? Did it even have a disk drive? The Atari 400 came out in 1979 and it was ALREADY more powerful than an IMSAI lol
@@James_Knott I believe I just said that lol it's such a trope Shatner makes fun of it in the Airplane sequel ua-cam.com/video/Ebo0aLLPYwA/v-deo.html
I built one of these High Nibble kits a couple of years ago. It sure plays a mean game of chess. The quality of the kit is outstanding, with incredible attention to detail and is only bettered by the quality of the emulation software.
Be aware that the way the clear Perspex back panel is held in the metal cover can result in the Perspex cracking and breaking off around the nut fixings (ask me how I know?). The solution is to superglue the four mysterious white Perspex reinforcements shown in the top left of the video at 11:56 to the clear Perspex back around the nuts. The reinforcement with the one corner missing goes in the corner beside the ESP32. It's obvious when you try it :-)
Thanks for the tip, I'm guessing that's something I don't want to discover the same way you had to.
I cracked sooo many acrylic panels in school. It’s so damn brittle
I built one of these kits too, they are extremely well made. The only weakness is as you mentioned, mounting the back panel to the frame. After I cracked mine too, a little 3d printing later and I have a solid mount. Highly recommend the 3d printed mount as it's hidden and much stronger than the acrylic. I think this is really the only weakness of this kit.
@@kaitlyn__LExtra fun when it's been exposed to sunlight for years and years. I was once hoping I could restore an early 3D printer. Nope, all the plastic parts fell apart in my hands.
I like that name “High Nibble” ... and his slogan, “For The More Significant Bits”. Obviously nothing to do with anything you might nibble to get high ...
My first computer ran on the S-100 bus. It was a North Star Horizon, dual floppy with an extravagant 16Kb of RAM. It ran North Start DOS. This computer did real work for sales invoices and inventory, using a Hazeltine 1520 in our family business. Later upgraded it up to 64Kb so as to run CP/M. Early days! Thanks for the video.
Thanks for the fond memories. I actually have an IMSAI 8080 system that I built in 1977.
One day I will look at refurbishing it (hasn't been powered up in about 40 years).
I will probably want to clean up the silver-plated chip leads that have turned black as well as replace the ginormous electrolytic capacitors in the power supply.
Same here - mine's been in the attic since the 80's. A fantastic machine at the time.
This brings back memories. An IMSAI 8080 was the first micro I ever worked with. I was at Hughes Research Labs at the time, at the tail end of the 70s. We had a tricked-out 8080 with dual floppies and a whole 16k of static RAM that ran an automated test setup another guy and myself put together. I’m hazy on the details, but think we used an IEEE-488 card in it to control a couple of digital multimeters and an X-Y probing station. I programmed it in Microsoft Basic under CP/M. Good times :-)
This series should be released as a podcast. I like to listen to these while driving
Hey, One I know very little about. Although back in the mid-2000s, because of the movie Pirates of the Silicon Valley (which desperately needs a remake with history beyond 1999), I figured this or an Altair would probably be the first switch computer I ever got my hands on. Nope, PiDP-11. And I ended up playing with a PDP-1 simulator before that. 😅
12:00 Easier method of Surface Mount Soldering (which is my favourite BTW): Tack the corners, Loads of solder, don't worry if you make shorts, cover all pads and legs, everything completely coated now?, lay solder braid across all the joints on an edge, sweep your iron across the braid, raise the braid and be amazed at your factory looking SMD job, repeat across other edges.
I used to hate Surface Mount Soldering until I saw one of Benjamin J. Heckendorn's tutorials on the subject. He made it extremely easy, and made me realise I was overcomplicating the job by trying to be too careful.
If you get solder paste in one of those dispenser syringes it allows you to put both solder and flux on the pad before applying heat, so you don't have to mess around with solder wire. It kinda works with an iron but it leaves many of the solder balls unmelted and floating around and you have to wash them off with isopropyl. Works much better with hot air and/or a hotplate. If I'm being lazy I will put paste on the pads and then hit like 4 legs at once(on an SOIC-8) with a 6mm chisel solder tip.
If you're going to use wire the most important thing is to get the half size wire! I don't know the exact measurement of it I think the normal wire like you have is 1mm and this stuff is like 0.5mm
The technique I used before that was like yours, put some solder down on one of the pads, clean and put flux on it and one end of the component, then with tweezers and the iron attach the component to that one soldered pad. Then for the other pads, lay the end of the wire down in the joint you want to solder and hit it with the iron. This limits the amount of solder to just that which is in the joint initially and you don't have to try to feed in a tiny amount of wire from the side.
At this point I dread through hole component much more because there's all the fiddling around with cutting the leads and they're a pain to clean all the burnt flux off of. Surface mount is quick and clean.
I should give the solder paste approach a try.
I remember watching this movie in the theater. It was one the reasons I got into IT.
Awesome. The IMSAI 8080 is one of my dream computers, even though I have no idea what I'd actually do with it.
Mine too, I was always fascinated by it. War games probably really helped that fascination along. That and it ignited my interest in modems.
That movie also gave the name to the technique of “war dialling”.
And what is also surprising is that the film also coined the very used word in the industry from there on: "firewall".
The IMSAI 8080 and the Polymorphics 88 (Poly 88) were what I learned BASIC programming on. The IMSAI took a few entries on the paddle switches to get the monitor code running, before we could work on actual programming.
I played a similar version of Spacewar in the early 80s on the TRS-80 Mod. 1. Back at that time, it was fun, at least for me. 24:45
I absolutely must get my hands on this, the web interface is second to none!
Great vid! Really interesting to me, as friends of my parents setup a computing shop in Epsom, Surrey, UK as an IMSAI dealership. They ploughed all of their savings into it and opened, after many teething problems. A week later IMSAI went bust… That was the end of that, really. They had to relocate to Yorkshire and start life over. I’m sure there are many other similarly sad tales.
That's really sad for them, I hope they where able to get their lives back on a even keel.
I don't know if it's the cadence, the accent or the Royal Mail rant, but this video has the best (and possibly longest) Alan Partridge impression I've ever heard. AAA++++ would watch again
FUN fact. I ordered this exact same kit. and I politely asked the creator of the kit to solder the surface mount parts as I have a tremor in my hand, and he obliged :) Its in the mail right now :) some heroes don't need capes.
Dave is the nicest guy, after I made this video he came over to the UK for retrofest in Cambridge. So I got to spend many a happy hour chatting to him while we drank a number of warm beers. Hopfully he'll get to come over again at some point.
They really should use a bitmap font to make that terminal feel a little more authentic.
Never thought I would see SMD inside an IMSAI! Imagine telling the creator that one day his machine would contain, and be emulated by a 32 bit microcontroller the size of a matchbox. Let alone - it has a web interface without the need of a modem! He would **not** have believed you. Great video BTW :-)
It still amazes me what we can now do with l microcontrollers. So much power for somthing so compact and cheap.
@@RetroBytesUK Yes, its mindboggling, compared to what we had to do in the 70's/80's to get embedded stuff going. Looking at the new Teensy's for example. Incredible.
You never know -- the designer of this machine is still around, although his "wild years" are long gone -- he may be watching right now? 😉
@@kwgm8578 Joe ?
I think he would be more blown away by the fact people can now wear computers that are a million times more powerful on their wrist.
My first computer was an IMSAI 8080, i bought in kit from from Byte Shop in June 1975, I had only 24K of RAM, and a few cards, one of which was a Cromemco Bytesaver 2708 eprom
programmer in which I burned a copy of Processor Technology's BASIC, I had the Processor Tech VDM-1 video card and their cassette interface (1200 baud). I had to install a line choke
on the AC line because my computer would reboot every time the refrigerator came on
Our UYK-7 system could boot form reel-to-reel tape, which would then utilize Winchester disks, but we still had to manually enter the initialization code via the main console switches. I think I only had to do it once (technically twice because I screwed up the first attempt, which was common). Eventually I became the “micro computer guy” and never had to deal with that antiquated POS again.
FYI: Troubleshooting the tape drives was a nightmare. I don’t think we ever had more than two of three functional at any given time.
I actually used WordStar to write Z80 assembly language programs... around 45 years ago. Thanks for the trip back in memory alley.
Even the "real" IMSAI 8080 and the "real" Altair 8800 still had fake front panels. Those CPU chips didn't have enough pins to directly have the front panel lights and switches connected. What happened was that the "front panel" actually consisted of a ROM chip with tiny programs that input/output the front panel switches/lights to the CPU via the regular input/output lines.
Nothing like the original PDP-8 etc, - especially the PDP-12 which was a GORGEOUS thing! - where the front panel switches and lights were directly connected to the circuits.
My school had one of these when I was in year 11. And an Altair 8800. They were so precious that us students were not allowed to use them. Sad really.
I worked at Computerland when I was young in 1985. Fun times.
lol, surface mount is easier than through hole, it just takes a little practice with the right iron tip. A J tip is mandatory imo. It’s shocking how much difference it makes.
PS great video, I have a High Nibble IMSAI 8080. It’s amazing.
surface mount stuff is so tiny though. very hard to not accidentally short things. also surface mount just sucks. I'm a systemelectronic engineer and i work in maintenance in a company producing cables. and fairly often some part of a machine will just randomly not work anymore at random amounts of time. its newer machines that have more problems compared to some old stuff from like the 70s and 80s.
@@SilasonLinux good flux like Amtech + a J tip on your iron makes even the fine pitch IC’s easy to solder.
I’ve been living abroad for a few years now and I think these videos have been what prevents me getting homesick
19:25 LGR would be drooling over the vintage woodgrain PC.
11:09 I can relate to that, I sometimes get calls from delivery people where they say nothing on my answering machine, they apparently can't read my intercom listing for my name, input four digit codes, or leave notice they had been there. It's either that or I've been home all day and I get a message "they just missed me".😒
It's interesting to see what home computing was like for before PCs, in that era you really had to be dedicated to computing and search out materials intensely, kind of reminds me of the early days of video exports or playing Japanese games before emulation Ie. full time job to get a hold of anything.
I worked and even Ran the Company named UltraByte, back in 76 -78 and we sold over 2000 of these IMSAI 8080's. Even 20 to NASA. Basic was the simple language.
Its loverly to know NASA bought some, that did not come up in my research. Thanks David.
I've got an unbuilt AC-30 on the shelf - new in the box, still in the bags. It looks awesome!
It really is a fantastic looking bit of kit, very of its time, and yet has aged well.
It's interesting, that in the War Games book it was Altair 8800 ...
You want to get some of that flux that Louis Rossmann uses. That shit's amazing! Makes light work of surface mount.
A friend of mine had an Altair. We had a lot of fun with it.
Great video, I remember using supercalc 2 at home on my cpm machine. Takes me back.
I was the first spread sheet program I was even shown.
@@RetroBytesUK I did a gcse computer science project on if computers or humans were able to provide better random numbers. By looking at the distribution and the mean I could determine that computer random numbers were better than a person, but groups of people were better than computers. Oddly but not included in my final results was that random numbers generated in sc2 under cpm on a z80 were significantly more random than numbers generated by sc2 under ms dos on an 8088. I never got to the reasoning why. But it was very repeatable
The IMSI HAD a memory mapped IO card called the VIO , it had 2 k of video ram and 2 k rom with a terminal emulator and a cpu monitor with memory read and write etc. also had an serial IMSI smart keyboard with programible keys. I just added a parallel dum keyboard unstead. word star intagrated with it and it was fast.....
When I was a kid, I strolled by the local electronics store to stare at the IMSAIs. ALTAIRs and SWTP computers of the day and imagine myself building my first S100 computer. It was probably fortunate that my first computer was an apple ][+; anything I built without any experience would likely have never worked.
I played a little bit with the MCI when it came out at one of the computer shows I went to, but I went to Apple as soon as I could
As someone who built a Heathkit H8 in 7th grade (took a weekend), you just earned a like & sub. Don’t know how this ended up in my recommended video list, but thank you UA-cam!
Thanks for the sub!
"MITS", not "MIT", for Micro Instrumentation and Telemetry Systems; they got their start making those two kinds of electronics for hobby rocketry and similar small missiles, then went into early calculator before producing the Altair 8800.
Absolutely elated to see a new video. Thank you.
Used the original in college. Even had a floppy (8inch) with CP/M. Fun!
I thought the two planes in ‘Dogfight’ were going to just fly into each other lol
Mini computer
Micro computer.
Where are we now?
Pico computer?
Nano computer?
I still have my old Altair. Haven't pulled it out in decades, but never getting rid of it =)
The easiest way to solder smd chips is to just solder 2 pins on opposite corners then drag the solder and iron across all pins it will bridge some thats ok then use solder wick and suck up the extra and the solder on bridged pins this method looks great and haven't ever had a bad solder joint
What’s the song during the soldering montage? Really digging that bass player.
There's something quick to try that might fix the vertical hold sync issue on your vt220. Take the case off and look on the lower right or left side for two turn-pots. One is the vertical hold, and it's worth a try to turn it back and forth a few times to clean the contact. This might fix it..
Thanks Joe, I'll give that a try. It would be great if that's all the issue is. I could do with out having another thing I need to recap.
Another beaut! Great video, I'll have a look for the kit.
If I didn’t know better I’d have said that montage tune was Jethro Tull
You mentioned the 4004. Well, I was disassembling a huge number of PC boards, and sorted the chips to be sold later. I had a number of chips I wasn't familiar with. Among them was an Intel 4040. I looked up the number, and couldn't believe what I had. I was a bit frustrated because I wanted to know what board it came from to see the support chips if any, and what it did. None the less, it is worth over $100.
Purchased my Apple IIe and Amiga 1000 from ComputerLand.
That was a long time ago......
Amgia 1000, so an early adopter of the amiga.
Thank you very much for this. Always enjoy your content.
Love your style and videos
Keep it up.
what's the DE/WM/theme you were using when you opened the TTY app thing?
yooooo, War Games (1983) IS MY FAVORITVE MOVIE
We have to give credit where credit is due. 👍
OK, now I'm curious how much allowance a teenager in 1983 would have to have to afford all the components of his computer. The computer was sold 1975 to 1979, but there couldn't have been that much of a price decay, right? Even if we assume he got it used from someone picking up something new and fancy, it seems way out of his budget. Or did prices fall off that hard after everyone moved on?
The twin 8" drive system he had with it would probably have cost more than the machine its self.
It’s like how Ferris Bueller had an E-mu Emulator, a bit of wish fulfilment for the audience ;)
To put the machine into context, David Lightman grew up as an only child in an upper middle class family. And that family was in bicycle range of Microsoft's headquarters, and Lightman had friends at Microsoft. Lightman's socioeconomic status is confirmed by seeing both parents with good paying careers, and a family home which had en suite bathrooms, well in 1983 that was hardly a normal feature in family homes at the time.
You're talking about a last generation computer in a rapidly evolving market.
In 1983 you could buy a Commodore 64 for $300 USD, the IMSAI 8080 was $400 USD new in 1976.
So the IMSAI in 1983 was 7 years old, pretty old for computer.
$400 USD in 1983 is worth the same as $1200USD in 2023 .
So it would be within reach for a teenager, especially one with rich parents.
But those twin 8" floppy drives would have been crazy expensive, a cassette tape interface would have been more 'in budget'.
While the IMSAI is iconic in this movie, I would have thought the C-64 would have been much more the tool of the 80's hacker, and much more likely to be owned by a teenager, you know, color graphics and games.
Bought in 78-79. CPU/MB/PS - $699, 16k Ram - $799 - 64k Ram $2799 - 2 CalComp142 8" FDD with DIO controller - $2999.
That’s so funny (or my cell phone is listening at me). I literally watched it yesterday evening again! After hunting for an IMSAI is the price. And even the kit is pricey but I may sway for that.
In uk the original machines go for scary amounts of money.
@@RetroBytesUK I noticed! I was browsing eBay yesterday evening most are in the US, so that’s completely out of the question with me residing in the The Netherland.
I saw one in the UK, the prices in your place are even worse than the US prices.
So I settled for watching WarGames instead 🤣But this kit is really nice also not cheap at woeien 270 euros but still better than 2400 quid or 2100 dollars. And both of without diskdrive!
I still have my IMSAI. It almost certainly needs new power supply caps :)
There's a thumb-wheel trimpot near the edge of the main board in a VT220 that, when it gets dirty over time, can cause that sort of vsync issue. You may just have to gently tweak it.
Thanks Eric, I going to give contact cleaning that pot a go. I'll see if adjusting it resolves my issue.
@RetroBytesUK on my vt220 all i had to do was tap it sharply with my finger. But i think i then cleaned it and readjusted it anyway. I found the solution in a very old comp.terminals posting
"Assuming Royal Mail uses a postman and not a ninja" = LOL 😅🤣😂😆
It's like listening to Alan Partridge talking tech....
... well, I know what I am asking Santa for this year...
11:30 - One superiority US mail has over UK mail. We don't need a card, just our license to walk in and get our missed packages. No fuss, no muss, and if the town is small enough you don't need a license after the first visit.
It would be really nice not to need the card.
New subscriber: this is brilliant. I have one of these kits waiting for my 1 year to pass since I haven’t had time to build it. 😂. Love the channel
The unbuilt kit sitting in the corner just begging to be built, its so nice when you finally find the time for it. I have a kim-1 replica kit just sitting there still waiting.
Yes I know it’s a kit, but still 10/10 for patience and skill Sir!
Regards from Brum! 👍🏼
the way he says PCB WAY makes me chuckle haha
Royal Mail Ninja, thanks, that made my day !
We love War Games because it is Romantic Comic Idyllicism from the 1980s. We don´t love postmodern media, because it is Ironic Comic Sadism or Ironic Tragic scapegoating
You sir, have earned my like, subscribe, and comment. Good job.
9:06 Black paper tape ... don’t recall having seen that before.
I really rather like the black paper tape, I don't think it's somthing I'd seen before either.
Do ... you ... want ... to ... play ... a ... game?
Could some party win majority in parliament entirely on the platform of “we’ll make Royal Mail wait for you to come to the door”?
Great video.
How about a video about mainframe computers, not just IBM, but Burrows and all the other mainframe computer manufacturers? As for IBM, how about discussing MVS?
Great… But… The loud vocal music absolutely wrecks your spoken track. Generally, you don’t need music at all, but if you feel like you have to use it, then make it much lower volume instrumental music in the background…
This is what we learned on in high school. Sometimes it worked.
Prepare for pedantic comments about how the 6502 isn’t a 6800 clone because it doesn’t run 6800 machine code. I got plenty of replies saying that, the last time I compared the Z80 to the 6502 in the exact way you did here 😅
@StringerNews1 thanks for proving my point!
It all depends on one’s definition of clone; and the 6501 was designed to be a drop-in replacement electrically, specifically conceived in the design phase as “the 6800 but actually affordable”. No one’s claiming it was exactly the same, everyone knew it had fewer registers etc.
Being able to plug in the exact same machine code is only one definition, and in practice doesn’t matter much as memory mapping etc can be so different that your code still won’t work on another machine. If you were editing the memory map anyway, it wasn’t that hard in most programs to change the registers or swap to using the stack to work with the 650X.
Just because it can’t run the exact code like a Z80 can with 8080 code, doesn’t mean they weren’t both conceived for the same purpose: a cheap alternative for a particular style of CPU.
Especially since most Z80 users also relied on Z80-exclusive functionality, so the 8080 code was getting partially rewritten anyway.
As far as the chip market is/was concerned, they’re both clones.
A computer designer intending to use an 8080 can use the Z80, and same for a computer designer using the 6800. Both can switch plans after the circuit board mask was already made - which is exactly why the lawsuit getting rid of the 6501 occurred and forced those customers to use 6502 with a pinout adapter.
BTW thanks for assuming I’m a CPU arch dummy 😘 I just don’t think being so prescriptive is useful.
Where most such nerds will go “ackshully it’s NOT a clone” in an adversarial way, people could instead start a more productive conversation about different types of cloning. But I hardly ever see the latter.
I considered snarkily asking if that mini essay was proof enough of my knowledge, but then I realised I don’t actually care.
Wanted one of these for a while. What was the royal mail ransom tax like on this?
In the US, we pronounce it "sodder", or simply sod for short. "Are you going to sod those chips onto the board?" 🤣
🤣
Careful running Zork, You are likely to be eaten by a Grue!
I can not recall the last time I enjoyed a video so much that made me fee so stupid.
Ever think about tinning up the contact pads first, then using a heat gun to surface mount solder the components?
Thank you very much for making an entertaining video.
That sneaky UA-cam algorithm got me to watch a video about this movie after several tries that I declined. I wonder if it has an agenda.
I'm just sittin here wonering how much somebody would charge to finish the surface mount stuff if I bought one.
I love retro, I love wargames, but not nearly enough to attempt surface mount!
It's easier than you think and there are guides-a-plenty on the web with a lot of great tips.
What the heck was R.A.L.F. from Wiz Kids? What monstrosity was that?
When the WarGames movie came out in 1983, the portrayed IMSAI was already painfully obsolete. This was intentional by the filmakers, who wanted to show how hacker-savy Matthew Broderick's character was even with old equipment.