Apple Printer on a Commodore PET
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- čas přidán 9. 09. 2021
- PET printers are hard to find and unique since they use GP-IB. So what if you didn't have to get one?
This is a video I've wanted to do for SO LONG and it's such a simple concept. But it has been fraught with issues every time I've tried to make it. So I decided that I would do it before moving and no matter what happened I would press on through and finish it. So it's not ideal, and very long, but I was at least able to do what I wanted and use the subject.
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So I actually found CMC and Richard Rosner, who wrote the word processing program. I'm emailing him a link to the video and hopefully y'all can connect!
Did he answer?
I have this theory that the words "I'm just quickly gonna..." are some kind of magic spell, which, when formulated (whether verbally or mentally, regardless of the language) actually invokes the forces of the universe to conspire against you.
Make haste slowly
Almost as dangerous as "This is simple" or "It'll be easy"
@@stinchjack Also called hurry up and wait
This video very accurately captures the frustration involved when messing with (old) computer stuff and little moments of pure happiness when things actually start to work.
Modern computer stuff can piss in your pocket the same way. "Computers are infuriating."
You're giving me flashbacks of when I connected my XT to a serial line printer (it was the size of a writing desk) using a custom cable I bought from someone at a swap meet. Man that thing was fast! I was probably 10 years old. That reminds me, I need to thank my Mom for being so supportive of my computer interest. This kind of stuff made me the CS engineer I am today.
I'm glad to see that printer user experience hasn't changed a whole lot over 40 years.
"Made by some dude in a shed" says the dude who makes random electronic in his apartment. LOL
6:59 AkBKukuU: "This is supposed to be a quick and simple video".
37 minutes later...
;)
At the end when everything finally works: _It's been 84 years_
As on many other BASIC's, the OPEN command tells the system to create a device descriptor (not sure if that's the right denomination but it's basically a handle) and assign a device to it. The first number is the device descriptor and the second number is the device. On Commodore computers, I think 0 is the screen and keyboard, 1 and 2 are the cassette recorders, 4 and 5 are printers, 8 and 9 are disks. So OPEN 130,4 opens the printer and assigns it to descriptor 130. Then you can use the device descriptor to do stuff with it, such as PRINT#130, "HELLO PRINTER". The command CMD redirects all command output to a device descriptor, so OPEN 130,4:CMD 130: LIST will print a listing to the printer. To make it stop, use CLOSE 130 (in this case).
Most of the time, it's easiest to use the same number for the device descriptor as the device, i.e. OPEN 4,4. But you can use variables too.
When you start a program using RUN, it resets all variables and probably also device descriptors. If you would have used GOTO 10 instead of RUN, your program that contained only PRINT#130,"BLABLA" commands, would have worked. You could have also used PRINT (not PRINT#) in your program, and used OPEN130,4:CMD4:RUN.
Reading data from an I/O port works the same as from the keyboard I think. If I remember correctly it's possible to use INPUT#130,"BLA BLA",A$ but that's probably not what you want. I think there are READ# and WRITE# commands to read and write data to and from a device descriptor which makes it possible to read and write data files to disk and tape, and it's even possible to create non-sequential files on disk, but you'll have to read the commodore BASIC manual for more information about that. I hope maybe you'll get back to that after you move to your new location. That 8050 disk drive is really awesome, you could store 512KB on one side of a double density floppy disk -- I was pretty disappointed when I used an IBM PC with the disappointing 360K storage on a double sided disk -- only a third of what the Commodore at my high school could do. Also the 8050 (and all other Commodore drives) are computers that you can program: You can write a program in Assembler (sorry no BASIC) and send it to the drive, and let the drive processor execute it from the RAM buffer.
IIRC, when you run a program, it resets all the file handles ON THE COMPUTER' END but does nothing on the device end. This is not a serious problem for a printer, but for a disk drive it means the drive's end of the logical file connection is now flapping loose, connected to nothing, and the drive doesn't even know to write whatever it has in a buffer to the disk. IIRC, you can fix this (more or less) by sending the Initialize command to the drive, but that is the drive's reset command, which means if you've changed the drive's ID number in software, it's no longer changed. (Putting external DIP switches for the drive number was the biggest QOL improvement on the 1571 over the 1541, even more than the optical track 0 sensor so it didn't bang it's head to death verifying head position or being double sided or being so much faster on a 128 in 128 mode.)
Oh, one important detail about writing drive executable programs: The dual-disk units have 2 different processors. Not one to run each drive, one to run both drives and the other to run all the external communications. That makes writing software for such a drive really interesting. (A 6502 does NOT like having a second processor running at the same time accessing the same memory. To make matters more fun, 6502's need to take the first two pages of memory, page 0 and page 1, for their own purposes. Page 0 is used in a number of special addressing modes that let it use fewer memory cycles by using 1 byte addresses instead of 2, and there's couple of ways it can use an address stored in zero page and either add an index register to it or use the other index register to step through memory to pick from a list of indirect addresses. Indirect addressing modes are powerful, and like all powerful tools, extremely dangerous if used carelessly. Page 1 is the hard-wired system stack page on a 6502. This all makes both the hardware and software design of Commodore dual-drive floppy disk units a great deal of fun. There's a reason they gave up on the 1572, the never completed dual-drive variant of the 1571. They weren't able to debug the damn thing properly.)
To print lower case, open with the cmd channel to 7, eg.
Open 4,4,7: print #4,"this is a test"
In the PRINT# command, the first parameter is the device handle (which you need to have opened in the current program, not the parent environment, as you saw. Everything after this I believe is parameters to print; commas will I believe space or tab separate parameters; in the example program they gave, A would have been an integer value assigned elsewhere, and GT$ would have been a string value; it would have printed those before the string literal, like: "432 VARIABLE_TEXT STRING LITERAL GOES HERE"
TT and LGR vid on the same day. Sweet! Best of luck with the move.
Great video. Love all the details and not skipping past the issues encountered when dealing with old hardware.
This channel is starting to remind me of Hand Tool Rescue. Which has been turning into more power tool and machine tool rescue of late. (But I am amused he seems to have derailed the plans of this guy who came up with a clever fractal-jawed vice that can hold objects of almost any shape...which was originally patented in 1913.)
Even at Commodore's height, their printers weren't the easiest to get a hold of, and some questioned whether they were worth the effort. So that's why a cottage industry to make these types of interfaces existed. But it was, as you observe, a cottage industry, especially early on. And that was something Jack Tramiel was fairly proud of. He wanted to make his money, but he was glad other people were able to profit off his stuff too.
You're make a WAY bigger deal about the hobby grade product properties than it really is. Outside of universities, this was a hobbyist computer. There were no (well, very few and far between) stores that sold this stuff back in the 70s. This was not the mid 80s when computers were everywhere and sold in Kmart and Sears. This was the 70s when nearly all of it was hobbyist and sold through mail order in the backs of magazines. This was the norm.
Just a couple of years prior, like literally 2 to 3, computers were sold as box of components.
The person most likely to buy this was one of the hobbyists who were only slightly behind the guys who literally bought a box of chips, resisters, capacitors etc and boards as their first computer.
The PET line was started in the 2nd wave of home micros. The problem was, the only major retailer that was involved in that launch was Radio Shack wit their TRS-80 Model I.That was, for most people, the only computer you could walk into a local shop and but at retail, so it was, for a while, the dominant machine in the market.
Otherwise, yeah, it was pretty much mail order, if you could even find an ad to order from as computer publications were a distinctly specialist thing before home computers took hold. And mail ordering a PET, with it's heavy yet delicate integrated monitor and heavy steel case was an expensive proposition.
@@evensgrey Yes. The PET was aimed at different people than was even an Atari 400/800. It was never aimed at families the way the Atari 8 bit line was nor was it sold at big box retail. I don't think he really grasps that.
My high school had two of the chicklet versions in 1978. Learned programming on them and my career was launched! And oddly, yesterday, I found a box in my garage with a cassette holder, and in it was my first ever program I wrote for the PET. Can't believe it! I think I placed it in that box in 1985 and totally forgot about it! The name of my program was "Star-Chase" where I used basic and 6052 machine code for speed.
I quite enjoyed seeing failure and being able to overcome it somehow. Thanks Shelby!
Yep. Agreed. Makes a good video.
I just wanted to watch a video about tech, but this guy just went off on a tangent.
Brought back a lot of memories when I worked at Ward's Computers, a Commodore dealer in Cincinnati.
Dont worry about putting too much time into editing I quite enjoyed this episode even without all the "normal" polish
I truly enjoyed watching you go through this, especially the frustration factor! This brings me back so much to the reality of using these kinds of devices. These kinds of small company devices were everywhere back then, and it was far more niche hobbyist using computers and trying to get things to talk to each other. Sure, we still have lots of proprietary things today, but there's so much more interoperability now than there was back then.
My uncle owned a small company called parallel technologies Incorporated up here in Washington That spent its early life making all kinds of niche products similar to this for the Apple 2.
I usually fix those type of keyboard contacts by gluing aluminum foil discs right to the carbon rubber pads. It's not pretty, but I've yet to have one fail.
thanks to you, the most important revelation to me this year is the existence of IEEE 488, and the vibrant ecosystem of things making such effective usage of it across multiple platforms. tbqh the 80s were pretty alright
so the 4 is the device number. The 130 is the channel, which can be anything between 1 and 255, take note that typically channel numbers above 127 turn on some feature. On Commodore printers using channels with the high bit set (above 127) enables the lowercase mode which replaces 1/2 the graphics character with lower case.
open 130,4 -- opens device four on channel 130
you can also use print# command to print to a specific channel
The cmd command redirects the output of the print command to the channel specified.
I'm sure that old line editor has a select print device command which is what you need to do to print something out with it.
If you want full a full serial interface, you need an rs232 adapter that goes in the user port. You can use terminals, modems, and even printers this way. The device you are using allows you to communicate with a serial printer the normal commodore way. Actual Commodre printers do have all the PET characters in them, the Apple printers does not.
Another amazing video Shelby. Always enjoyable. I hope you have good luck finding a place. Ill try to support the channel as much as possible.
Your number of supporters has certainly expanded.
Your frustration shows why this product is made the way it is. It wasn't designed for the general public, it was designed for pet owners who knew how to use a pet and who understood commodore idiosyncrasies.
The way you deal with peripherals in commodore basic is through the open command. It's very odd. I had to learn all this crap in the 80s. This is why most people didn't own computers back then. For the VAST majority of people they were little more than eye cue (sic) tests and really complicated ways of doing very uninteresting things most people didn't need to do.
I really like the way the PET opens up like a hood on the front of a car thats so cool and makes it easier to work on
The determination is off the charts here 👏
This is true vintage computing
This actually had the feel of one of your old videos, very nostalgic
I'm sorry you struggled so much, but this was hilarious to watch. I loved this.
Neat! I have a SWTPC PR-40 I'm trying to get working. While researching it I found documentation that explains how to connect it to a PET. It and a PET 2001 would be an interesting pairing as contemporaries of one another.
You can print out that word processor source code on the printer to analyse it... :) :) :)
Still enjoying the content, Thanks sir
Great video Shelby. But you're missing the crucial fix for integrating Commodore and Apple equipment: copious amounts of beer.
For your PET's keyboard, try getting some of the conductive paint that comes in a little bottle for repairing remote controls and things like that. I had the same sort of issues with my 8032's keyboard, and the repairs using that stuff seem to be holding up ok. Should work on any of those conductive-rubber-plunger-on-copper-fingers type of keyboards and keypad matrices. Cool video!
reminds me of learning the kaypro's word processor, I ended up using the default text editor instead, CP/M is a different beast to learn
There were few GPIB-to-serial adapters, but there were LOTS of serialized-GPIB to Centronics (that is, the most common parallel printer interface, the one on the other end of the parallel printer cable for a IBM PC) adapters, and there were also serialized-GPIB to parallel-GPIB adapters (which were able to be pretty simple because they only needed to switch from serial to parallel because the data formats and command formats were the same).
Who, exactly says or ever said that hooking a Commodore machine to an Apple printer is even discouraged, let alone a heresy? This kind of thing was incredibly common. Maybe not this particular adapter, but they made these by the bucket load.
The adapter needs to have some brains, though. Commodore expected a fairly smart peripheral. Most other manufacturer's machines didn't. Apple machines in particular usually ran most of their peripherals under direct system control.
@@evensgrey To do anything fancy, yes.
@@tarstarkusz Actually, I was particularly thinking of floppy drives, which were under the direct control of the host system in the Apple ][ series. No on-board brains at all, compared to the Commodore floppy drives, which had one or two 6502 processors on board. (They each had as many processors as floppy drives, although in the dual units one ran the drives and the other the external communications. Given the requirements and proclivities of the 6502, that made for interesting hardware and software design.)
@@evensgrey It allowed the computers to be cheaper, but it made the floppy drives more expensive. Given the 64, which has this setup was the best selling computer of all time, they made the right choice. Probably wouldn't have been the best selling computer of all time if they had made different design choices.
67458 is larger than 65535, which is the largest address a 6502 can address. (the address bus is 16 bits) You are misremembering the number. The special characters with the shift is normal.
I think he's thinking of 64738, which if i'm not mistaken is the place you sys to hard reset a c64.
I worked with lots of serial and parallel printers in the 80's, and I don't recall reading data back from them. There just wasn't much need to do so. Life was simpler.
You can use an ATTiny85 to replace all of the logic on the printer and give it a new serial interface. I love old stuff, but I am all for upgrading the brains of things.
Ah, printing in the 8-bit era. Endlessly flipping DIP-switches, each piece of software needing individual configuration. And if you, like me, live in a country with a national character set you were in for yet another world of utter frustration, very rarely were you able to get a setup where all characters came out right. And when the first laser printers appeared that somehow managed to make configuration even more aggravating. I'm at good terms with most tech, except printers, and that can probably be traced back to those years.
You're giving me bad vi flashbacks 🤣
I'm reminded of the MS-DOS program EDLIN
I really don't miss it very much.
I assume the reason for the 15V PSU is possibly to make sure there is enough headroom for a 7812 voltage regulator that's probably used in the GPIB adaptor as they need 2V iirc more than the rated output voltage. Most PSU's back then were unregulated so the output voltage would vary with line voltage and load so unsuitable for sensitive electronics without some further proper voltage regulation.
Your suffering is our entertainment. Thank you.
>hastily records video during a move
>the video is 45 minutes long
also
>repair keyboard
because Murphy's law.
Hey, I thought last night I was going to use Manjaro MATE but encountered Bluetooth issues on my current machine, yet _somehow_ Manjaro KDE works just fine live and post-install. So Idefk what was going on with that, but by the time I was actually doing something I wasted quite a few hours.
@@bluephreakr you switch from pulseaudio to pipewire?
@@armanelgtron4533 Pipewire has been integrated into my distribution of preference.
I suspect this would happen if you decided to opt for the software.
1. Send CMC your warranty card by mail.
2. CMC receives it and puts a big red stamp on the card marked SENT so you can’t send it in again.
3. Makes a note in your file (your PAPER file) to keep for their records. MAYBE they have an Apple ][ with VisiCalc.
4. Packs your warranty card AND the software in a mailing envelope, and maybe adds return receipt, then sends you the whole thing along with a thank you card.
5. A few days later you’d receive everything so you could use your new device.
Ghod, how did we even live in the 70s/80s?
back in the day we had adapters to allow paralell printers to be used with a C-64. Many would show symbols as the key strokes in brackets
I was able to use my PET 2001 with an HP 132 column daisy wheel printer using only a GPIB to IEEE-448 cable. It worked natively with no problem.
The commands for reading data back are GET# and INPUT#, for a single character and a string terminated by a Carriage Return, respectively.
You use them like this:
GET#x, A$
INPUT#x, B$
In both cases, x is the file handle, which you have to create using an OPEN command (OPEN x, device#, device# is normally 4 on a printer, these are more complex for a device like a disk drive which an do many more things), and A$ and B$ are string variables, needed to hold what's going to be character data. (They can hold 8-bit characters, so they may not have any meaning to the screen display subroutines of the PET.)
About all you can get from a printer is a status code, and even then it requires the printer actually send them and the interface actually converts them and make them available on the GPIB interface. A lot of serial printers for the home market didn't do that, mostly because they didn't need to. You could just look at it to check the status lights.
Part of the frustration with this set up probably comes from the fact that the interface isn't as smart as a Commodore printer would have been. Most Commodore GPIB connected devices (both parallel and serial versions) were at least as powerful a computer as the computer using them. In the case of that disk unit, twice as powerful as the PET, since the disk unit has two 6502's driving it, while the PET only has one.
Man, if you would like to speed up your production with videos like this, I don't think it would be bad. This still has an incredible production value for me and maybe you are requiring too much from yourself.
Long story short: I like this video a lot and I wouldn't notice that was a video made in a hurry if you didn't repeat that many times during the record.
Good luck moving to the new house :)
Hmm, back when I was originally using Commodore 8-bit computers: 64 first, then 128; and a reasonably compatible printer, the BMC BX-80 (also with an interface somewhat similar to this one; and I can't remember why my dad didn't just buy us a Commodore 1525/-6 or MPS 801/-2/-3 instead, and I can't ask him now, and he probably wouldn't remember if he were still with us), we never had do do anything about baud rate. I didn't even know printers had such a thing. All these years I thought baud rate was just for modems. Ours had one wire with a pass-through card that went to the tape drive connector for some odd reason, and I don't remember the interface having its own power adaptor. I still have it but it's quite "buried" at the moment. But come to think of it, we did have some of those little switches (probably DIP) on the _interface_ to mess around with; I just never remembered them as being for baud.
I lived this in the early 80s. Printers on Unix VMS systems, terminals over leased line 1200 baud modems etc etc. frustrating back the and just as frustrating now. Computers suck, yet I love tinkering with them, there must be something wrong with me.
variable capacitors are not a good idea, they drift so bad
So long as you redirect to the printer that is all you need and would want in the day.
"Print#" is one of the commands. It didn't like the space because it didn't recognize "print #" as one of the commands.
And here I was proud of the wrongness I was regularly committing by using an Apple Imagewriter II with my Tandy 1000. The cable's the only really hard part there.
"This exact box..."
* "This exact _model_ of box."
Oh, I didn't realize that was just a project box from electronics/hobby stores, etc.
Wow, what a weird word processor! I don't think I could function with that. The first WP we bought was Easy Script. It was pretty... well... "EASY" in comparison!
Instead of using graphite from a pencil on the pet keyboard, you could use those "graphite thermal pads" wich are more solid, and provably do give a way better contact. And being a pad, you cant cut and glue them as you like
did the same with a pc with a translation software to emulate fx80 with an apple compatible printer
I think you would need some sort of time sharing device/software to get a terminal to both send and receive from the Pet. I have no idea if that was a thing for a computer of this processing power.
The arcane editor vaguely reminds of edlin for MS-DOS / Windows NT.
Or Vi for linux
Cool video though, thanks!
that is some hardware way before my time.. any chances of reviewing a pc that resembles like the grid compass pc in the future ?
OK, let's talk about those questions at the end... A modem or terminal would have normally connected to that other mystery port in the back, called the user port. An RS-232 interface to the user port is fairly simple (2 chips I think). THAT connection would be bi-directional. I think the user port is device#2. To read and write you'd use the commands INPUT# and PRINT# (which you already used). So it would be something along the lines of this:
1 OPEN 2,2
10 PRINT#2,"SENDING DATA."
20 INPUT#2, A$
30 PRINT A$
As for decent word processors, I think Paper Clip and Word Pro were two reasonably good ones for the PET. (I'm more of a 64/128 guy.) Question is whether you can find them on TAP files. But those two, if I'm correct that there were PET versions, would be worth finding. They were much better than what you had on the video.
Noting the "key cuts" in the passthru connector and matching them to the back of the computer would have assisted you in getting the correct port and orientation.
I believe there is a parallel printer adapter for Commodore PET/CBMs that plugs into the User Port; but I'm much more interested in the adapter you showed today 👍😊
As for the IEEE-488 GPIB interface, yes, just like the floppy drive it can obviously read data back; can the APA 1450 interface? It might be able to report back an out of paper error.
I would advise you to use aluminium tape for the keyboard, rather than graphite, I did this trick on my PET 2001 and it works all the time without a problem.
Time to go on fleabay and buy a pack of 100 thin conductive silicone rubber disks, and use some silicone to redo all the keys. Sold to repair keyboards that are doing exactly what the PEt one is doing. You might have to carefully slice the old ones off though.
You know you are being so critical when people had to hand write or type college work. Primitive these things may have been but the difference these systems made to tasks were so much greater than the incremental changes now. They made the near impossible, reasonable even if not easy.
Problem using the Apple printer is it can't print special characters as the PET used PETSCII not ASCII.
The PETSCII characters are used extensively in BASIC programs as control codes to clear the screen, move cursors etc. So printing a listing won't print the control characters and you kiss important parts of the program.
There were some EPSON printers that came in both PETSCII and ASCII versions the only difference being the character set ROM.
But even without that card-edge pass-through, wouldn't you be able to connect an actual IEEE-488/GPIB printer to it via the back of the disk drive, with the other kind of cable (maybe 488 on both ends)? Also, since you can still connect both up using this style of cabling system instead, why leave them disconnected as if you want to make sure you don't use the floppy drive unless you have to?
There has to be a system command that lets you save machine code that was supplied on tape to another tape or disc.
Not such a "short video" after all. 😁
i wish i knew basic, but i was born 1980 and didnt use any computer but the apple ii in school and i only used a few things on disk. now i have a vic 20, trs 80 coco 2, ibm 5150, apple iie enhanced, trs 80 model 3 and a radioshack mc-10 which i dont count. it sits in its box. so i am limited to what i can do with any of them.
Wish you had opened that box. We like it if you take time to look at the details.
CmC WP reminds of edlin/ed. Real word processors start at line zero :-)
from back when it was a real accomplihsment to actually
print anything. ANyway, I think that the bidirectional means that the thing can report back to the computer, if the printer allows it, not that it can be inserted reverse
If you were going to load the program _off of_ a .tap file, then what were you going to load it *FROM?*
Haha, "new" was the best thing you ever did with that WP program!
But why did you think you needed to restart the computer, as if "new" wouldn't clear the BASIC code well enough?
Are you sure this program predates the computer, if it was made for the 4016 and 4032 that came out in 1979 (I used the 40xx in 1979 at school as a kid)?
Why would it be important to keep the warranty card anyway? Sending that in wouldn't really cause any limitation, would it? It would just register it for the warranty purpose and also get you your software. And if you wanted your copy of it just for keepsake, you could just make a photocopy of it either by using a copy machine or taking an actual photo of it (back then it would be on film, though, of course, so most people would probably think twice before doing that)?
15 volts DC. Power voltage for Cisco DPC series cable modems. Everyone else is 12 VDC. Only Cisco wants 15.
How would you read data into a computer back from an output-only device, anyway?
I too have a PET with a keyboard that acts persnickety every single time I fire it up.
Printers always seem to cause problems back in the day 😂
Where do you go to buy "tractor" paper?
Please open up the video list for your channel on your phone (in the official CZcams app) and I think you will see why you probably need to put your logo back where it used to be in the thumbnail. ☺
Is it just me or is that printed list of supporters at the end getting longer? EDIT: Pretty soon you're going to have to get one of those high-speed line printers! 😁
Hope the move went well!
Dude! Your the guy I need info from lol. I'm a musician, who needs a computer that can run a DAW (digital audio workstation) The problem is, I "HATE" modern PC's and I can't stress that enough, for many reasons, bloatware being at the top of the list and the fact that modern PC's have no style to them. They just look terrible to me.
I have always loved old PC's like the Commodore Pet or the Compaq Portable III system, they just look awesome. Is it possible to upgrade those to run a DAW? And also a mouse? lol The mouse is a must :D
Poking to address 67458 within a 64KB address space does not make sense :-)
26:20-26:24 Can I have this by itself as a reaction video? I love computers so much and by all rights, they should be predictable, but sometimes that's just not the case.
im waiting for "putting a Porsche engine in a 1967 VW beetle"
"As best I can"?
* The best I can. ("Best" isn't something that's adjustable and thus comparable with an "as.")
Why wouldn't that WP be designed for printers? What good would a WP be without a printer?
hmmm "GT" is probably "getTime" since it was going to print the time?
Some dude in a shed that was funny has hell
Yeah, it's interesting that in the case of opening and closing those channels, the program ignores what was set up in direct mode, even though strings and variables can be set in direct mode and then the program can use them as-is. And I don't even know why there has to be an "open" statement anyway, when the "print#4" ought to take care of that by itself. The same with the more complex disk commands. It seems redundant to me. Why can't they just always be open, and only receive data when you send "print#" to them? Of course you don't know that; I'm just asking it "to the air."
Wow, adjusting an analog component like a capacitor or potentiometer for a digital setting like either baud or BPS is kind of strange.
That program gives me vi flashbacks
A lot of those power adaptors regulated to DC right inside themselves. Why is that so surprising to you?