Definitely liking the hardware deep dives into the peripheral chips. Interesting to see the deep levels of integration they were able to do and writing small device drivers is one of my favourite things.
Another reason for Baudot code to use inverse frequency order is how it was originally input: an operator manually entered each character by pressing (or not pressing) keys on a five-key keyboard, 2 keys under the left hand and 3 under the right. This bit arrangement meant that the most common characters needed the fewest keys pressed to type them.
Wow, that would have been painful, I only know back to the early Siemens 100 telex machines - hand coding baudo at any speed sounds like a real challenge, although if you were coming from Morse code, maybe not that hard
I had used a Bardot tty in the army, but the tty and paper tape in the video are. ASCII, 8 BIT as someone else noted. For a data acquisition system,I use a sphere 6800 based setup and loaded Microsoft 4K basic to it from paper tape. That took 45 minutes, I immediately saved it to 8 inch floppy disk 128 bye sectors.
Yeah, I'm running the hack to "return RUclips dislikes" Why would anyone (16 so far) dislike a video like this. No one makes you watch it. There are very few still capable of troubleshooting this old hardware, fewer still willing to. I just don't understand people. Thanks Dave, I know this isn't going to change the world, but it certainly is bringing back memories and showing just how bright the early developers were. I'll be here 'till the end.
I had a similar computer to the KIM-1 called a TEC-1. Hex keyboard & 7seg displays, only it was Z80 based. My dad had one of those teletypes and I used to save my assembler programs on it. This KIM-1 of yours is bringing back memories.
Like you it was the first computer I ever got my hands on, also at school, in the UK. We though didn't have a fancy pants teletype terminal. everything was input on the hex keypad and output on the 7-segment based display. Programs were (unreliably) stored on audio tape. Thanks so much, I’m filled with nostalgia. It, and the ZX81 changed my life.
Brings back memories. I not only programmed through the ASR-33, but did the maintenance on it, the SEL mainframe to which it was attached and all the associated peripherals (magnetic tape drives, 10MB disk drives, 132 column line printer etc.) back in the mid 70's. This all while in the military. The training and experience I got allowed me later to have a long career in aerospace.
I never got serial to work on my KIM-1 using the same Corsham board. I never thought to check if my KIM-1 was modified... I certainly will now! Thanks for the inspiration and great videos
I do enjoy your videos, keep them coming. I started with a card punch, card sorter, and card reader, with overnight scheduling to run your code, and picking up your output the next day, because the University placed a premium on the use of teletypes to where the students in general could not afford to use them. If I remember right, they had a Burroughs system. Sadly, I had to throw out my paper tape, cards, and the like about 15 years ago in a move. The oldest stuff I got left is a couple of Osbornes (off white/blue edition), with 5 1/4 floppies of some programs and CPM OS. At this point I don't know if any of it still works as floppy disks lose their magnetism over time, but hey, it's cool to have.
It appears that I have transgressed the unwritten law ( in RUclips) tried posting some information on where a few tons of DEC equipment went. Messages post then vanish. Oh well .
I really enjoy the deep dives into this old stuff. As a kid, I remember drooling over the likes of SWTPC, IMSAI, and Vector Graphics, and literally wearing out the Heathkit catalog. I got my BSEE, specializing in digital design. I love these old systems; they are simple enough for someone to understand what's going on.
For the KIM-1 Microsoft BASIC, you are better off just hitting 'ENTER' at the memory size prompt. It will start and the end of BASIC and probe its way upward until it runs into non-RAM. You can PRINT FRE(0) to see the amount of free space that is available. The only reason you'd want to manually enter a value is if you have code loaded in high upper RAM that you want to make sure BASIC doesn't clobber, but I'd imagine any such RAM wold go in the lower 5K RAM space of the KIM-1.
I was taught basic on a Teletype ASR 33 attached to a Wang minicomputer. Paper tape was out "mass storage" It was upper case only. It is said some of Unix /Linux's cryptic commands come from avoiding typing much on the Teletype terminals. They had a very heavy keystroke. Pie plates were used to store our coils of paper tape. With the source , basic can be extended freely. Well within the limits of your Ram and rom. I have an Aim 65 . It is essentially, the keyboard extension of the kim. a 20 character display and adding machine like printer are its terminal. It will be great to see more of this historic machine.
I have always been interested in early computers like the KIM 1 and this was a great explanation! I used to hate math growing up, but since learning about computers and how binary works, I am so fascinated by it. Thanks Dave, great information.
Very early computer actually did NOT use binary math ! Well into the 1960s, they used Binary Coded Decimal (BCD) for arithmetic operation. 4 bit could encode all digits from 0-9.
My final year university project used a SYM-1 (the UK version of the KIM-1) to control a 'robot' chassis - two windscreen wiper motors for movement, ultrasonic and bumper collision detection, hand made encoders for speed and position calculation and all the code was hand assembled and entered via the hex keypad
I was sceptical towards your Channel for too long, Dave. Great work. I'm so gonna use your videos to teach my daughter IT for her GCSE- big thanks. IT Legend
Just gave Inverse frequency a few minutes and came up with the following list - Fewer Holes means: Stronger Tapes Faster Printing 1) Based on original manual keying method Faster Printing 2) Better waste management with fewer 'dots' to exhaust (less manual emptying) Faster Printing 3) Better Temperature management on punch solenoids Fewer write errors (miss-punched - based on a fixed error rate) Fewer read errors (obscured holes - based on a fixed error rate) Better Longevity on write punch equipment.
History of these machines is so fascinating. I grew up with a c64 and loved it. Kids today just can’t understand what it was like without these great videos you make.
The ETAOIN SHRDLU sequence, while indeed reflecting English letter frequency, comes from the keyboard arrangement on the old Linotype typesetting machines, which was also frequency-ordered I guess to help the machine operators set type faster.
There is a beautiful documentary from 1978 titled "Farewell, Etaoin Shrdlu" on Vimeo that shows the final day of printing with the Linotype at the New York Times.
When I was younger (iBC.. Before Creation of the internet) I worked out my own version of this and remember mine as ETAONRISHDLUC and can’t recall the rest. I use it often in hangman game and it works well most of the time. It was based on the letter frequency of use from English (Australian or British) encyclopedias at the time. That sequence is somewhat dependent on what country and year it was based on. I’d imagine in the future it will be based on TLAs, L337 and SMS or internet jargon 😀
Indeed, and it's basically the equivalent of a modern "asdf". Back in the day, when you made a typesetting mistake, it would be easier and faster to cast the slug, throw it into the melting pot and re-type the phrase, so Linotype operators just marked their mistakes with a nonsensical bunch of characters.
KIM-1 used the 6530 RIOT which is a Ram/Rom Input/Output-Timer variant. Atari used by far the most 6532s - probably 30-35 million in 2600s and another few million in 8-bit peripherals.
This is really cool. I'm getting a lot of flashbacks to Ben Eaters breadboard computer. It looks like the KIM was using very similar logic with it's addressing.
Happy days at college, programming my BBC Micro's PIO User Port at address &FE60, with the Data Direction Register (DDR) at &FE62 - and all in 6502 assembler. Thirty-five years later, and I can still hook up my old college project (a simple spoken command interpreter), to that same BBC Micro, loading the code from the same floppies - and everything still works like a dream.
Your computer history videos are so interesting. That's why I keep coming back to your channel and also why you are my favorite RUclipsr. Keep up the good work, Dave!
Ah brings back memories of converting a KSR 33 with dial-up modem to current loop used by all the SEL computers we were running back in the day. The interesting things you find out they did to make one system work and then backing those changes out.
This is where the real magic lives! I learned about these chips with Atari and Apple computers. I love this stuff and it has come in handy many times fixing things. Older industrial gear remains useful and these topics speaks to what one needs to fix and use that gear. Too much fun Dave!
My stepfather bought some RCA single board computer with a calculator type terminal on the end of a thick ribbon cable. It had prototyping PCB space and LEDs. We did put a program in it to add 2 + 2 but after that we could not see what the point of the thing was. It was not until he bought a proper desktop computer Superbrain Z80 with integrated screen, keyboard and floppy drives that I was able to figure out what a computer was and what it could do. That RCA thing was just too obscure to get my head round.
This series is very interesting to me. I was born in 78 but I remember the TRS80 era machines. It's amazing what humanity had to go through to get to super computers in our pockets
Great video! In middle technical school in the 90’s we were taught about the 8086 and chips surrounding It. But It took them forever to explain what you just did in minutes. Of course you’ll need to know stuff to understand other stuff and I probably didn’t know enough back then. Most certainly i’ll enjoy a deeper dive.
The teletype makes me think of Saturday afternoons watching the live football scores go past on TV. The screen would be split in 2, and the bottom part(about 1/5th of the screen) would be taken up with a camera pointing at a teletype that would give a printout of the updated score, time of goal and name of the player who scored every time a goal was scored, as well as half time and full time scores. This still goes on this day using digital means on BBC1, but they still pipe in the teletype sounds. Keep in mind for this, there's a TV blackout on football between 3-5pm on Saturdays here. The talk about the RIOT chip makes me think of a C64 tape game that said it used more memory than normally available because it would turn off I/O lines the game didn't need to gain a bit of RAM back without bank switching. I assume that this is related to how the RIOT(or CIA in this case) is mapped into the memory addresses. I still have that game on tape, but I can't play it without using an emulator because I lost the copy protection booklet.
Enjoy hearing about, yes. Enjoy doing... not so much. It reminds me of programming a PDP 7, which I was given brief opportunities in college lab to do.
Originally, the ASR/KSR 33 Teletype 33 came with a 20 mA "current loop" serial interface. This allowed fairly long (100s of feet?) cables to be used to drive it. VT220 were actually the fourth generation of "glass teletype" from Digital Equipment Corporation (DEC). The followed the VT05, the VT50/52 and the VT100 family.
I am new to Ardino and i understood 70% if this. But its amazing to see this old hardware getting a new life by someone who is so passionate about it. I love the videos!
Baudot code is a perfect example of variable length encoding, allowing for efficient serial transmission / increasing transfer speed of English language-specific content. Another example of the variable length encoding is Morse code.
I still have my Dragon 32 which is basically a TRS-80 Color Computer. 6809 CPU and 32k of RAM 16k ROM and 16k expansion ROM. I learned to program in Assembler on that.
The ASR33 teletype reader (110 bps) was not much faster than typing :) I used it in the early seventies to develop device drivers for our OS, after half a year I switched to synchronous displays (24x80 chars) in a multi-drop configuration with say 12 displays sharing one 9600 bps line. The fun things was, that in my previous department I tested the prototypes of that data-communication hardware. Once there was a problem with the data communication in our computer center after a modification, so they did sent me downstairs to solve it. That was much faster than calling the official service organization, especially since ~12 displays were unusable.
3:20 "fewer holes are better" without knowing the construction, I'd assume that every paper chip has a chance to go somewhere it shouldn't. So fewer paper chips might also mean longer service intervals.
We used a KIM-1 for the Modern Physics lab. Programs were stored on cassette tape (on a Radio Shack player). I remember copying the program and typing it into the KIM-1, messing up and having to start over (because it couldn't read the program last stored on the tape- gah!).
We had a number of Teletypes that we used to load programs into a DEC PDP-8. The tapes were fragile, especially when loaded contently. We ended up using Mylar tape for many of the programs. they were tough to punch, but survived
In a world across the pond, we had the BBC micro. A 6502 at the heart and a pair of 6522 VIAs (from memory (there is a joke there (see my self out))). One VIA did 'user port' and the other did 'printer'. Truth was you could mess with either. I seem to remember that the DIY eprom programmer from BeeBug magazine(?) used both ports for Address and Data busses and control. Anybody? I was ~15 and I'm 51 now.... and I've a beer since then.
I like this series a lot. I was 13 when the KIM-1 came out, but did not get interested in electronics until I was around 16-17 y/o. Then because I loved arcade games, I got interested in computers and bought a TRS-80 Color Computer w/ 4K RAM for $399 in late 1981 early 1982. Loved computers/electronics ever since and I became a programmer. Even though I never owned a KIM-1 I love learning about computers from this era -- including the SWTPC 6800, Altair and IMSAI computers. You should get those as well and do a series on them!! :) :) :) ...
Loving these KIM videos, please continue exploring! :) This is such rare hardware these days, most people will never see a KIM in real life, much less be able to play with one. Given the tremendous importance of the 6502 chip, and seeing this is how it all began, I consider this important history and treasure every video I get.
excellent breakdown of the KIM's 6530s function and how memory is addressed on the KIM. I learned new things today, thanks. I would like to add that the extra 128 bytes of RAM was critically important to some programmers. A text adventure game for the bare KIM is Kim-Venture written by Bob Leedom in the 70's uses all of the 1152 bytes available minus six bytes. It was hand complied by the author and is a masterpiece of coding efficiency.
Thanks Dave, educational and enjoyable as usual! I have a definitive memory of (seeing my dad…) being able to run communication with old VT 100 much faster than 4800 baud. Now feeling the urge to try to fire up the KIM-1 rev b that I have successfully hidden every time “someone”has wanted to rid the house from useless stuff (-:
Same chip MOS marketed to Atari for use in their 2600 console back in the day, though they only used one. It's one of 3 major parts along with a watered down 6502 (6507) which is actually the smallest package of the three. Interesting! Oh, and I would say "First" but this project deserves more respect than that.
Not so much a "watered down 6502", but a 6502 with a reduced pin count. It turns out that external pins were a major source of the cost of ICs back in the day. Internally, a 6507 is a 6502. Incidentally, this is also why Mostek ended up dominating the DRAM market: multiplexing helped reduce pin count, and thus costs and board sizes, because you had to route fewer traces, so the extra logic to support multiplexing made sense.
Wow - that brought back memories of some of my first college gear in the mid -late 80s. Teletypes, papertapes and having to set the memory map. ( that got me into 6502 assembly to get the hardware to read and control external electronics , which paid well for a while)
The Intel 4004 is the first microprocessor, and did have I/O instructions. It too targetted calculators initially. In the real big computer world, the IBM System/360 (big) line had one I/O instruction, SIO - Start I/O. External hardware executed the channel (I/O) program. On the later System/370 line I got to use the operating systm macro instruction, EXCP, to write and execute my own channel programs.
Aha …. This video is a perfect example of what my digita1 Fonts controllers were doing … aka Teletype font ⚛️⏰✅🔑 TTY font used with teleport , telephony and teleprompt FONTS. Like a calculator the fonts could be used to compress and/or encrypt data . It’s great to see the hardware of how all this is strung together. Like Mp3 .wav
Hello Dave, I really like and enjoy your videos, and also your book about autism. I have never thought about it too much, but it is very interesting to read your very detailed description and explanition of your thoughts of autism, and how well you have analyzed your personal thoughts about it. I am a retired electrical engineer and learned to program when only Fortran was taught and Basic was brand new. we had to program Fortran on a coding sheet and then have it punched for input on paper tape or cards by the key-punch operater. Machine language was also around, of course, and Assembly. My interest was circuit design (TTL & analog), System design and RF fields and waves. I have built a lot of systems around DEC PDP/11s, VAX 780s, Data General and ModComp computers. I was also a HAM a long time ago, and one had to learn Morse code. I believe your questions about inverse character utilization and holes punched in paper tape relate back to sending code. It was important to send code at a high rate, and this was more quickly sent by the most- used characters being the shortest, i.e. the ' E ' and such. Maybe some others have mentioned this, but it seems so obvious to an old HAM! Congratulations on a great career, MS-DOS and Windows development and your many accomplishments with MicroSoft. It appears to me, that your eye-contact is perfect.! Keep Up the GOOD Work!
Excellent video Dave. Made sense to me. I'm not old enough to have ever used punched tape but I was taught by those who did. My first proper job after university involved assembly language with Zilog Z8 microcontrollers (not to be confused with Z80 microprocessors) and RS232 UARTS and 74LS logic chips and stuff like that. Still looking after some of them today.
sadly im old enough to remember kim, but my fav was a pet computer, learned machine code ,basic, and got the bug for programming from that day forward.
everyone interested in this subject would probably like catching the latest Floppy Days Vintage Computing podcast where the person that wrote the floating point of the first MS BASIC for the MITS Altair is interviewed - the person that owns the title of being THE first MS employee (albeit only briefly for a summer)
Love these videos Dave. Maybe progress from the Kim1 to the PET, c64, c128 and Amiga, showing how chips improved with each generation. That would be fun.
This is awesome and kind of what I am doing to learn more of how a computer works. I may even start off with a breadboard computer project made mostly out of logic ICs and move up from there to microprocessor, micro controller and maybe FPGA. Computers have gotten boring now. I think I would be much further and had a lot more fun with them if I started out in the wild west home brew days when you were soldering your own boards together.
About 99% of this is over my head, yet I find it absolutely fascinating, and can't wait for more!
Same here. If he was speaking in Koine Greek I wouldn't understand less.
It's sinking in somewhere.
Someday you might be doing some arduino crap and it'll all come together in your head lol
whaaaaa COOL!!
Ah. The eternal "I am le dumb" comment. Why are you even watching this?
Ah. The eternal “I am le autist” comment on RUclips. Why are you even interacting with people? Shouldn’t you be locked up somewhere?
Nowadays few people know this. I really appreciate you sharing that vintage architecture. It is a very important video.
Definitely liking the hardware deep dives into the peripheral chips. Interesting to see the deep levels of integration they were able to do and writing small device drivers is one of my favourite things.
Too bad you don't work for HP their drivers are so bloated!
These KIM videos have been my favorite of all your videos to date. Tinkering on and investigating old equipment is very interesting.
Another reason for Baudot code to use inverse frequency order is how it was originally input: an operator manually entered each character by pressing (or not pressing) keys on a five-key keyboard, 2 keys under the left hand and 3 under the right. This bit arrangement meant that the most common characters needed the fewest keys pressed to type them.
wasnt even morse code intended to work that way?
Wow, that would have been painful, I only know back to the early Siemens 100 telex machines - hand coding baudo at any speed sounds like a real challenge, although if you were coming from Morse code, maybe not that hard
I had used a Bardot tty in the army, but the tty and paper tape in the video are. ASCII, 8 BIT as someone else noted.
For a data acquisition system,I use a sphere 6800 based setup and loaded Microsoft 4K basic to it from paper tape. That took 45 minutes, I immediately saved it to 8 inch floppy disk 128 bye sectors.
Yeah, I'm running the hack to "return RUclips dislikes" Why would anyone (16 so far) dislike a video like this. No one makes you watch it. There are very few still capable of troubleshooting this old hardware, fewer still willing to. I just don't understand people.
Thanks Dave, I know this isn't going to change the world, but it certainly is bringing back memories and showing just how bright the early developers were. I'll be here 'till the end.
Definitely, all dislike of the video are wrong click on the Smartphone
I’ve disliked a couple of videos before, but it was accidental. Most likely that’s the primary reason for most of the dislikes.
I had a similar computer to the KIM-1 called a TEC-1. Hex keyboard & 7seg displays, only it was Z80 based. My dad had one of those teletypes and I used to save my assembler programs on it. This KIM-1 of yours is bringing back memories.
Like you it was the first computer I ever got my hands on, also at school, in the UK. We though didn't have a fancy pants teletype terminal. everything was input on the hex keypad and output on the 7-segment based display. Programs were (unreliably) stored on audio tape. Thanks so much, I’m filled with nostalgia. It, and the ZX81 changed my life.
Brings back memories. I not only programmed through the ASR-33, but did the maintenance on it, the SEL mainframe to which it was attached and all the associated peripherals (magnetic tape drives, 10MB disk drives, 132 column line printer etc.) back in the mid 70's. This all while in the military. The training and experience I got allowed me later to have a long career in aerospace.
Loving this KIM1 series Dave. I'm fully liked and subscribed!
I never got serial to work on my KIM-1 using the same Corsham board. I never thought to check if my KIM-1 was modified... I certainly will now! Thanks for the inspiration and great videos
I do enjoy your videos, keep them coming.
I started with a card punch, card sorter, and card reader, with overnight scheduling to run your code, and picking up your output the next day, because the University placed a premium on the use of teletypes to where the students in general could not afford to use them. If I remember right, they had a Burroughs system. Sadly, I had to throw out my paper tape, cards, and the like about 15 years ago in a move.
The oldest stuff I got left is a couple of Osbornes (off white/blue edition), with 5 1/4 floppies of some programs and CPM OS. At this point I don't know if any of it still works as floppy disks lose their magnetism over time, but hey, it's cool to have.
Has me thinking about digging out my old KIM and seeing if it still works. Then again the SuperPet is gathering dust too.
Hold on now. This isn't Gary Gough of Regina is it? If so, please tell you have a PDP-11 somewhere still...
@@DavesGarage looked, saw at least an 11/04 in the inventory.
🇨🇦!
It appears that I have transgressed the unwritten law ( in RUclips) tried posting some information on where a few tons of DEC equipment went. Messages post then vanish. Oh well .
@@DavesGarage I am indeed myself, actually in Regina right now.
Might be he most concise explanation of how ICs are memory mapped I’ve ever seen. Excellent work.
I really enjoy the deep dives into this old stuff. As a kid, I remember drooling over the likes of SWTPC, IMSAI, and Vector Graphics, and literally wearing out the Heathkit catalog. I got my BSEE, specializing in digital design. I love these old systems; they are simple enough for someone to understand what's going on.
For the KIM-1 Microsoft BASIC, you are better off just hitting 'ENTER' at the memory size prompt. It will start and the end of BASIC and probe its way upward until it runs into non-RAM.
You can PRINT FRE(0) to see the amount of free space that is available.
The only reason you'd want to manually enter a value is if you have code loaded in high upper RAM that you want to make sure BASIC doesn't clobber, but I'd imagine any such RAM wold go in the lower 5K RAM space of the KIM-1.
You have connected so many concepts in my mind. Genuinely, thank you for your work and sharing it with us.
I once have an MPF-1 (Micro Professor I, Z80) board.
I was taught basic on a Teletype ASR 33 attached to a Wang minicomputer. Paper tape was out "mass storage" It was upper case only. It is said some of Unix /Linux's cryptic commands come from avoiding typing much on the Teletype terminals. They had a very heavy keystroke. Pie plates were used to store our coils of paper tape. With the source , basic can be extended freely. Well within the limits of your Ram and rom. I have an Aim 65 . It is essentially, the keyboard extension of the kim. a 20 character display and adding machine like printer are its terminal. It will be great to see more of this historic machine.
I have always been interested in early computers like the KIM 1 and this was a great explanation! I used to hate math growing up, but since learning about computers and how binary works, I am so fascinated by it. Thanks Dave, great information.
Very early computer actually did NOT use binary math ! Well into the 1960s, they used Binary Coded Decimal (BCD) for arithmetic operation. 4 bit could encode all digits from 0-9.
My final year university project used a SYM-1 (the UK version of the KIM-1) to control a 'robot' chassis - two windscreen wiper motors for movement, ultrasonic and bumper collision detection, hand made encoders for speed and position calculation and all the code was hand assembled and entered via the hex keypad
I was sceptical towards your Channel for too long, Dave. Great work. I'm so gonna use your videos to teach my daughter IT for her GCSE- big thanks. IT Legend
Just gave Inverse frequency a few minutes and came up with the following list - Fewer Holes means:
Stronger Tapes
Faster Printing 1) Based on original manual keying method
Faster Printing 2) Better waste management with fewer 'dots' to exhaust (less manual emptying)
Faster Printing 3) Better Temperature management on punch solenoids
Fewer write errors (miss-punched - based on a fixed error rate)
Fewer read errors (obscured holes - based on a fixed error rate)
Better Longevity on write punch equipment.
History of these machines is so fascinating. I grew up with a c64 and loved it. Kids today just can’t understand what it was like without these great videos you make.
The ETAOIN SHRDLU sequence, while indeed reflecting English letter frequency, comes from the keyboard arrangement on the old Linotype typesetting machines, which was also frequency-ordered I guess to help the machine operators set type faster.
There is a beautiful documentary from 1978 titled "Farewell, Etaoin Shrdlu" on Vimeo that shows the final day of printing with the Linotype at the New York Times.
When I was younger (iBC.. Before Creation of the internet) I worked out my own version of this and remember mine as ETAONRISHDLUC and can’t recall the rest. I use it often in hangman game and it works well most of the time. It was based on the letter frequency of use from English (Australian or British) encyclopedias at the time. That sequence is somewhat dependent on what country and year it was based on. I’d imagine in the future it will be based on TLAs, L337 and SMS or internet jargon 😀
cool!
Indeed, and it's basically the equivalent of a modern "asdf". Back in the day, when you made a typesetting mistake, it would be easier and faster to cast the slug, throw it into the melting pot and re-type the phrase, so Linotype operators just marked their mistakes with a nonsensical bunch of characters.
I don't understand much about the inner workings of a computer, But I always feel like I understand a tiny bit more after watching you
Yay, my day just got better!
KIM-1 used the 6530 RIOT which is a Ram/Rom Input/Output-Timer variant. Atari used by far the most 6532s - probably 30-35 million in 2600s and another few million in 8-bit peripherals.
ironic that Atari had to buy all those chips from commodore after commodore bought MOS.
Hardware level videos are always enjoyable.
This is really cool. I'm getting a lot of flashbacks to Ben Eaters breadboard computer. It looks like the KIM was using very similar logic with it's addressing.
Happy days at college, programming my BBC Micro's PIO User Port at address &FE60, with the Data Direction Register (DDR) at &FE62 - and all in 6502 assembler. Thirty-five years later, and I can still hook up my old college project (a simple spoken command interpreter), to that same BBC Micro, loading the code from the same floppies - and everything still works like a dream.
I watch this channel every day even though I understand like 1 out of 10 concepts
Absolutely do like. I saw my 1st and only KIM-1 strapped to the top of a educational robot in tech college many years ago.
Your computer history videos are so interesting. That's why I keep coming back to your channel and also why you are my favorite RUclipsr. Keep up the good work, Dave!
Ah brings back memories of converting a KSR 33 with dial-up modem to current loop used by all the SEL computers we were running back in the day. The interesting things you find out they did to make one system work and then backing those changes out.
Thanks Dave, keep it up. This pre-dates my computer usage by 3 years, but it’s super interesting!
This is pretty cool. I like the deep delve into the history of computing.
This is where the real magic lives! I learned about these chips with Atari and Apple computers. I love this stuff and it has come in handy many times fixing things. Older industrial gear remains useful and these topics speaks to what one needs to fix and use that gear.
Too much fun Dave!
If Dave Plummer had worked at NASA,
he'd be known as "a steely-eyed missile man".
Love it Dave. I so wanted a KIM-1 back in the late 70’s. I had to settle for a COSMAC Elf with an RCA 1802 cpu. Keep these videos coming!
My stepfather bought some RCA single board computer with a calculator type terminal on the end of a thick ribbon cable. It had prototyping PCB space and LEDs. We did put a program in it to add 2 + 2 but after that we could not see what the point of the thing was. It was not until he bought a proper desktop computer Superbrain Z80 with integrated screen, keyboard and floppy drives that I was able to figure out what a computer was and what it could do. That RCA thing was just too obscure to get my head round.
This series is very interesting to me. I was born in 78 but I remember the TRS80 era machines. It's amazing what humanity had to go through to get to super computers in our pockets
Great video! In middle technical school in the 90’s we were taught about the 8086 and chips surrounding It. But It took them forever to explain what you just did in minutes. Of course you’ll need to know stuff to understand other stuff and I probably didn’t know enough back then. Most certainly i’ll enjoy a deeper dive.
We used paper tapes on our high speed IBM printers back in the early 70s, hooked up to a 1401 (1) and the 360-160 (3)
The teletype makes me think of Saturday afternoons watching the live football scores go past on TV. The screen would be split in 2, and the bottom part(about 1/5th of the screen) would be taken up with a camera pointing at a teletype that would give a printout of the updated score, time of goal and name of the player who scored every time a goal was scored, as well as half time and full time scores. This still goes on this day using digital means on BBC1, but they still pipe in the teletype sounds. Keep in mind for this, there's a TV blackout on football between 3-5pm on Saturdays here.
The talk about the RIOT chip makes me think of a C64 tape game that said it used more memory than normally available because it would turn off I/O lines the game didn't need to gain a bit of RAM back without bank switching. I assume that this is related to how the RIOT(or CIA in this case) is mapped into the memory addresses. I still have that game on tape, but I can't play it without using an emulator because I lost the copy protection booklet.
Enjoy hearing about, yes. Enjoy doing... not so much. It reminds me of programming a PDP 7, which I was given brief opportunities in college lab to do.
Originally, the ASR/KSR 33 Teletype 33 came with a 20 mA "current loop" serial interface. This allowed fairly long (100s of feet?) cables to be used to drive it.
VT220 were actually the fourth generation of "glass teletype" from Digital Equipment Corporation (DEC). The followed the VT05, the VT50/52 and the VT100 family.
Loving the KIM-1 stuff, Dave. Looking forward to the next one.
I am new to Ardino and i understood 70% if this.
But its amazing to see this old hardware getting a new life by someone who is so passionate about it. I love the videos!
Too many memories. I had a SCAMP before progressing to a OSI with three CPU's, 6502, 6800, Z80. A teletype was my printer.
Baudot code is a perfect example of variable length encoding, allowing for efficient serial transmission / increasing transfer speed of English language-specific content. Another example of the variable length encoding is Morse code.
Loving these deep dives. Thanks for sharing.
Fascinating. I think the oldest machine I have fond memories of using was the TRS-80 model 2.
I still have my Dragon 32 which is basically a TRS-80 Color Computer. 6809 CPU and 32k of RAM 16k ROM and 16k expansion ROM. I learned to program in Assembler on that.
this is a comment to feed the algorithm, to help you have the desire to keep making videos on the KIM - you'll get at least one more "watch" :)
Awsome Dave, really takes me bk, cheers, n enjoying!!!
Great Video! Like a fire hose if information. You must have been so pumped when that transistor worked ! Congratulations .
The ASR33 teletype reader (110 bps) was not much faster than typing :) I used it in the early seventies to develop device drivers for our OS, after half a year I switched to synchronous displays (24x80 chars) in a multi-drop configuration with say 12 displays sharing one 9600 bps line. The fun things was, that in my previous department I tested the prototypes of that data-communication hardware. Once there was a problem with the data communication in our computer center after a modification, so they did sent me downstairs to solve it. That was much faster than calling the official service organization, especially since ~12 displays were unusable.
Interesting factoid: etaoin shrill we’re the first two columns on a Lino-Type machine, and we’re used to flag a slug with errors.
3:20 "fewer holes are better" without knowing the construction, I'd assume that every paper chip has a chance to go somewhere it shouldn't. So fewer paper chips might also mean longer service intervals.
This is some useful knowledge for my recently completed RC2014(z80 solder yourself kit).
We used a KIM-1 for the Modern Physics lab. Programs were stored on cassette tape (on a Radio Shack player). I remember copying the program and typing it into the KIM-1, messing up and having to start over (because it couldn't read the program last stored on the tape- gah!).
We had a number of Teletypes that we used to load programs into a DEC PDP-8. The tapes were fragile, especially when loaded contently. We ended up using Mylar tape for many of the programs. they were tough to punch, but survived
In a world across the pond, we had the BBC micro. A 6502 at the heart and a pair of 6522 VIAs (from memory (there is a joke there (see my self out))). One VIA did 'user port' and the other did 'printer'. Truth was you could mess with either. I seem to remember that the DIY eprom programmer from BeeBug magazine(?) used both ports for Address and Data busses and control. Anybody? I was ~15 and I'm 51 now.... and I've a beer since then.
See if you can type MEMORY SIZE? A - In my old OSI C1P it said "WRITTEN BY RICHARD W. WEILAND."
I like this series a lot. I was 13 when the KIM-1 came out, but did not get interested in electronics until I was around 16-17 y/o. Then because I loved arcade games, I got interested in computers and bought a TRS-80 Color Computer w/ 4K RAM for $399 in late 1981 early 1982. Loved computers/electronics ever since and I became a programmer. Even though I never owned a KIM-1 I love learning about computers from this era -- including the SWTPC 6800, Altair and IMSAI computers. You should get those as well and do a series on them!! :) :) :) ...
Loving these KIM videos, please continue exploring! :)
This is such rare hardware these days, most people will never see a KIM in real life, much less be able to play with one. Given the tremendous importance of the 6502 chip, and seeing this is how it all began, I consider this important history and treasure every video I get.
There are kits!
Dave, this video (and pretty much all of your others) is pure gold! You know your stuff sir :-)
Wow, thanks!
excellent breakdown of the KIM's 6530s function and how memory is addressed on the KIM. I learned new things today, thanks. I would like to add that the extra 128 bytes of RAM was critically important to some programmers. A text adventure game for the bare KIM is Kim-Venture written by Bob Leedom in the 70's uses all of the 1152 bytes available minus six bytes. It was hand complied by the author and is a masterpiece of coding efficiency.
Ahhhh now this is cool. I can't resist old hardware!
The joys of system programming. Keep it up!
Kim One and the Riot Chips is such a good name for a math rock band
This is awesome!! I can't wait for the next episode!
Thanks Dave, educational and enjoyable as usual! I have a definitive memory of (seeing my dad…) being able to run communication with old VT 100 much faster than 4800 baud.
Now feeling the urge to try to fire up the KIM-1 rev b that I have successfully hidden every time “someone”has wanted to rid the house from useless stuff (-:
Excellent overview of memory decoding, as many other things
Definitely interest in more of this series here.
Same chip MOS marketed to Atari for use in their 2600 console back in the day, though they only used one. It's one of 3 major parts along with a watered down 6502 (6507) which is actually the smallest package of the three. Interesting!
Oh, and I would say "First" but this project deserves more respect than that.
Not so much a "watered down 6502", but a 6502 with a reduced pin count. It turns out that external pins were a major source of the cost of ICs back in the day. Internally, a 6507 is a 6502.
Incidentally, this is also why Mostek ended up dominating the DRAM market: multiplexing helped reduce pin count, and thus costs and board sizes, because you had to route fewer traces, so the extra logic to support multiplexing made sense.
I used this Teletype in 1974 and HP basic at the uiversity. That was exciting.
Wow - that brought back memories of some of my first college gear in the mid -late 80s. Teletypes, papertapes and having to set the memory map. ( that got me into 6502 assembly to get the hardware to read and control external electronics , which paid well for a while)
The Intel 4004 is the first microprocessor, and did have I/O instructions. It too targetted calculators initially.
In the real big computer world, the IBM System/360 (big) line had one I/O instruction, SIO - Start I/O. External hardware executed the channel (I/O) program.
On the later System/370 line I got to use the operating systm macro instruction, EXCP, to write and execute my own channel programs.
There is interest. Thank you and glory to The Algorithm! May the interactions with your videos help spread the channel across RUclips!
Aha …. This video is a perfect example of what my digita1 Fonts controllers were doing … aka Teletype font ⚛️⏰✅🔑 TTY font used with teleport , telephony and teleprompt FONTS.
Like a calculator the fonts could be used to compress and/or encrypt data . It’s great to see the hardware of how all this is strung together.
Like Mp3 .wav
Hello Dave, I really like and enjoy your videos, and also your book about autism. I have never thought about it too much, but it is very interesting to read your very detailed description and explanition of your thoughts of autism, and how well you have analyzed your personal thoughts about it.
I am a retired electrical engineer and learned to program when only Fortran was taught and Basic was brand new. we had to program Fortran on a coding sheet and then have it punched for input on paper tape or cards by the key-punch operater. Machine language was also around, of course, and Assembly. My interest was circuit design (TTL & analog), System design and RF fields and waves. I have built a lot of systems around DEC PDP/11s, VAX 780s, Data General and ModComp computers. I was also a HAM a long time ago, and one had to learn Morse code.
I believe your questions about inverse character utilization and holes punched in paper tape relate back to sending code. It was important to send code at a high rate, and this was more quickly sent by the most- used characters being the shortest, i.e. the ' E ' and such.
Maybe some others have mentioned this, but it seems so obvious to an old HAM!
Congratulations on a great career, MS-DOS and Windows development and your many accomplishments with MicroSoft. It appears to me, that your eye-contact is perfect.!
Keep Up the GOOD Work!
pretty cool video!! Brings back memories from the day.
Again, great video, Dave! Thanks!
Commenting to drive engagement! I am loving this series, keep it up!
Love this series.
Love the fact you played with sexy Amiga's. I have worked with A500 & A4000T, still have a running A1200
Hi Dave, and thanks for sharing your knowledge on these things, and detailed workarounds you done to get things working on KIM-1. Awesome stuff ;-)
Wow. Very cool. I'm in awe!
Excellent video Dave. Made sense to me. I'm not old enough to have ever used punched tape but I was taught by those who did. My first proper job after university involved assembly language with Zilog Z8 microcontrollers (not to be confused with Z80 microprocessors) and RS232 UARTS and 74LS logic chips and stuff like that. Still looking after some of them today.
Dave,please keep your excellent videos coming. Stuart from Melbourne AU
I LOVE this series! please keep it up
First video for me. Loved it immensely! Subbed.
sadly im old enough to remember kim, but my fav was a pet computer, learned machine code ,basic, and got the bug for programming from that day forward.
Amazing stuff Dave thank you
Was anyone else distracted by the cool tire table like I was?
everyone interested in this subject would probably like catching the latest Floppy Days Vintage Computing podcast where the person that wrote the floating point of the first MS BASIC for the MITS Altair is interviewed - the person that owns the title of being THE first MS employee (albeit only briefly for a summer)
I miss the chairs for our little friends outro . . .
Love these videos Dave. Maybe progress from the Kim1 to the PET, c64, c128 and Amiga, showing how chips improved with each generation. That would be fun.
6502 stuff is just simple enough that understanding the steps in these videos isn't hard. Hope to see more KIM-1 stuff
This is awesome and kind of what I am doing to learn more of how a computer works. I may even start off with a breadboard computer project made mostly out of logic ICs and move up from there to microprocessor, micro controller and maybe FPGA. Computers have gotten boring now. I think I would be much further and had a lot more fun with them if I started out in the wild west home brew days when you were soldering your own boards together.
dave I am certainly enjoying this deep dive into the kim-1! I wish I could get my RevE to work!
Good video Dave! Thanks for sharing it with us!👍💖😎JP