1980 Terminal with Linux - TeleVideo 950

The first thing I wanted to get back up and running after getting my capacitor reforming setup done was my S-100 stuff, but I'm going to need a terminal to use those computers so we're starting with this deceptive looking Televideo 950!
More on reforming capacitors: • Reforming Capacitors -...
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[@Xarius86]

It actually kind of makes sense that the "back space" goes back a space, and the "delete" key actually deletes a character.

[@user-fh2fm7vr4m]

This is my experience with AS/400 as well, at least thru terminal emulators.

[@southernflatland]

back space backs a space delete key deletes a key Gotcha 👍

[@randomdesign6304]

That's how they worked back in the day, including on DEC VT terminals. So it's not a weird mapping, it's correct by design.

[@deang5622]

Backspace goes back a single character, not a space.

[@tramadol42]

​@@randomdesign6304 Absolutely, it went so far that on the keyboard of my good old Siemens terminal, the key has a double label: "Backspace / Backstep". Together with the Shift key, it sends the code for "Delete".

[@KnutBluetooth]

There's no fundamental reason why all the features of this terminal do not work with Linux. The termcap definition is just incomplete/wrong. Someone just needed to get some basic stuff working with this terminal and submitted an incomplete/wrong definition and no one has cared ever since. Just like there are tons of non standard keyboards that don't have proper definitions that don't work fully with Linux because no one bothered. Maybe try with a BSD.

[@athompso99]

In general, Linux and the major BSD flavours all share the same ncurses-supplied termcap, so this sadly probably won't make any difference. If you want a proper tvi950 termcap, you might have to go back to the SunOS 4.x era, maybe a 2nd-gen SVR4 system like Unixware. [Source: I am a termcap/terminfo author for several terminals, but not the TVIs.]

[@nickwallette6201]

So true. Linux _seems_ like it has all this support for a huge variety of platforms and modular components, but in reality, if you're not running it on x86 hardware with a modern ANSI-like terminal and a recent GCC with full GNU life support system, well... good luck to you, sir.

[@KnutBluetooth]

@@nickwallette6201 I'd go further and say that Linux only runs well on hardware that is 1) supported by hardware vendor employees that contribute to the kernel 2) hardware that is used by big companies who can pay for employees to fix bugs in the kernel 3) hardware that is used personally by Linux kernel programmers. Outside of that sooner or later, you're out of luck because of the constant code churn in the kernel breaking things without testing on hardware that doesn't fall in the three cases I mentioned. These days Linux crashes all the time on the very same 32-bit hardware where it used to work flawlessly (no regressions with the appropriate Windows, so it isn't a hardware malfunction). I had to buy another damn video card recently because AMD employees that "maintain" Radeon stuff in the kernel do not fix any bugs for perfectly working hardware they deem "too old". On the other hand, I don't think you really need GNU stuff. Alpine with musl/busybox works fine.

[@nickwallette6201]

@@KnutBluetooth That's very true. I have a VIA Epia board that is pretty much unusable on recent x86-32 Linux due to various hard lock-ups and extremely poor throughput on at least the IDE half of a PCI controller card under the sata_promise driver. Also tried to use a Matrox G200 on another older box, figuring that ought to have great driver support. Nope. Completely broken. Just random garbage on the screen. I do love open source projects, but the downside of no official support channel is that code maintenance follows volunteer dopamine.

[@KnutBluetooth]

@@nickwallette6201 Except for hardware vendors who are quick to abandon support for their own stuff, I don't blame them. I'd be even willing to pay a reasonable amount of money so that kernel programmers could be hired publicly to maintain older hardware in Linux. But I'm pretty sure this would be opposed ruthlessly with lobbying just like 'right to repair" laws.

[@Foobar_The_Fat_Penguin]

22:41: Just for the record: SystemD is event driven, so you can actually configure the units to only start agetty when the USB adapter is plugged in. It's also possible to use udev to do that but going via SystemD might be more elegant. Of course, it probably doesn't make a lot of sense to go through that hassle for a one-off presentation.

[@hobbified]

The events are coing from udev either way, it's just a question of whether it works better for you to have udev do a thing, or have udev tell systemd to do a thing.

[@johndododoe1411]

SystemD is decades removed from traditional POSIX/Unix systems that were born for serial and considered the local PC as just a serial terminal sharing some of the computer hardware. I'm old enough to have used the original tools on Linux machines with no local screen at all. I have also used a real terminal connected to a VAX .

[@AddicteServer]

And there is a pre configured one "agetty@ttyS0 or getty@ttyS0"

[@phiwise_9489]

I love how this video is half "Retro hardware repair" and half "Wizard explains how not to luse with unix; luses anyway". Very aligned to my particular interests!

[@sadmac356]

Same honestly

[@ppokorny99]

I disagree with the statement that 25 pin connectors had more flow control. IBM introduced the 9pin version because its smaller and it has all the serial handshake lines that are used for rs-232 communication to modems common in the 80’s. Tx, rx, Cts, rts, dtr, dsr, cd, ring, gnd. The 25 pin connector has other pins defined for synchronous serial clock signals, secondary serial channels, and a bunch of unused or reserved pins. None of which were useful for a pc connected to a common async telephone modem or serial printer.

[@ChrisGonnerman]

Most of the extra signals of the DB25 version weren't used by basically anything by the '80's. Not sure how much they were used before that, as I started college in 1983 and that's when I started getting serial terminal experience. Used to know the main pinouts for a "proper" null modem cable by heart. GND is GND, RX crosses TX, DTR crosses DSR, RTS crosses CTS. Just don't remember the numbers now.

[@CORBARocks]

Watching the terminal setup on Linux reminds me of doing that with a Unix System 3 with 24 serial ports...around 1983. I used to carry a rs232c 25/9 pin breakout box with LEDs and a peg matrix around in my pocket all the time!

[@beatadalhagen]

I love the beep. Had one of these with a modem in 1995. If not this exact model, then close. Ah, the days of Gopher and Annex.

[@TheGreatAtario]

Very early in my programming career, it became my job to write terminfo files for clients to be able to use our product's Unix version with all the formatting and whatnot that could be mustered on whatever hardware they bought, since the built-in ones were either insufficient, wrong, or missing entirely. And a short while before that, I had used many different hardware terminals in college, where the TVI950 was a staple. Big nostalgia here!

[@ChrisGonnerman]

Yeah, I wrote termcap and terminfo files for various terminals on a variety of mid to late '80's Unix systems. That was... fun... for some definition of fun anyway. Never used a TVI950 but spent a lot of hours programming a Motorola 68000-based computer using a Motorola M220 terminal. Even played around (in off duty time) with reloading character sets.

[@TheGreatAtario]

@@ChrisGonnerman Unix terminfo authorship fistbump!

[@ChrisGonnerman]

@@TheGreatAtario Thanks. Not the most fun things I've done in service to the computers, but neither is it the worst.

[@JeffreyGroves]

You should be using the `reset` command when changing term types too. You may even need to cycle power on the terminal if the terminal gets really freaked out.

[@RocketCityTech]

It is absolutely amazing that this series of serial adapters can interface with USB and therefore a modern computer, especially given the age of this hardware. Truly amazing!

[@cnvogel]

Fun fact: the old televideo terminals were used in the video War Games :) (I checked the rom dump of a 912 and built a PC font from it, it’s identical)

[@TastyBusiness]

Man, that thing is filthy. Excellent practical demonstration of the capacitor reforming decision tree. I wasn't expecting to see a 6502 family of parts in there. CRT cataracts are the degradation/oxidization of the epoxy layer between the safety layer and the glass of the CRT itself, rather than mold. Great video, glad to see the TV950 in action!

[@widicamdotnet]

Support for 40+ year old serial terminals in Linux is actually surprisingly good, considering much newer stuff has already been thrown out of the mainline kernel. Like 486 CPUs or IrDA adapters...

[@PinguimFU]

Wait irda was also thrown out? 😮

[@JdeBP]

Well strictly speaking the terminfo support isn't anything to do with Linux, as it's not done by the kernel at all. All that Linux deals with is the serial port, and ironically that is _not_ 40 years old. it's a relatively new USB device, which one wouldn't have had 40 years ago. So Linux is supporting a quite recent device, and it's only the non-Linux part of the operating system (Linux being the kernel, of course) that is supporting the 40 year old stuff. Using a PC that has an honest-to-goodness serial port on the mainboard would be more like Linux supporting old stuff. (-:

[@gamagama69]

@@JdeBP i mean a lot of modern motherboards have a serial header through the superio. i have one with a port adapter and im curious if this would work with this. just dont have room for a massive terminal that i realistically have no use for but i kidna really want one to screw around with

[@DasIllu]

I did something like this with a Zenith EasyPC 20 years ago. That thing had barely more cpu power than a terminal. It only had a "mouse port". Well, it actually was a serial port with a lot of stripped pins of D9 connector. Configuration was a lot easier since i could just use a dos terminal program. Midnight Commander was the end boss when battling code pages and terminal configs. In the end it really looked like a terminal from the mid to late 80s. With Lynx i could even browse the web (back then it was easier).

[@FinnBojorgensen]

Lovely ! Brings me back to the good old days when VT100 was the state of art and I had to play with termcap entries, escape sequences etc. I suppose that many of your younger followers were somewhat puzzled by all the techspeak, but to me, it brought back fond memories.

[@harveyellis6758]

I have lots of memories working with old terminals. I had 6502 based terminal in my garage (with colour capability) in mid 1990's. It was connected via serial to PC in house running a Slackware distribution of Linux. Lots of hours spent with termcap, configurations, and trying to get terminal compatibility to present data correctly on the crt.

[@afshinrohani]

Your videos bring me immense joy. Even in areas that aren't my specific interest. Your dedication and care is rewarding within itself.

[@pkneeyahx]

How can you get anything done with those two Hydro Thunders in there! Lol

[@MileZero313]

Lmao so true

[@frugalprepper]

I remember back in the day, I used to work with serial communication all the time on AIX and HP, System V and HP-UX. I also did a lot of CNC machines in shops. I was the serial master. I remember one tech had been at a customer for a week trying to get a Fiber Serial MUX working on a AIX it basically took 16 Serials to dumb terminals over Multimode fiber to another building. Back in the day before IP and Telnet were really a thing. I had it working in about 2hrs. Had to loop 4 and 5 and 6,8.20, set it up for software flow control. I still have my breakout box. Every once in a while it still comes in handy.

[@MarkyShaw]

This was a great lesson in serial connections in general. I appreciate you sharing all that info about terminfo, termcap, and screen. I was struggling big time with my TRS Model 102 and connecting to a Pi. It worked but I couldn't get the nonsensical characters to go away despite changing term types. The screen trick worked! Now I have another use for screen other than keeping my IRC session running in the background ;-)

[@Dinnye01]

Shelby, you are like a drop of water in a desert. While a lot of your videos may not have any effect on my life, but it is always lovely to listen to your voice and wisdom.

[@Throckmorton.Scribblemonger]

"you are like a drop of water in a desert" Insignificant?

[@Dinnye01]

@@Throckmorton.Scribblemonger Don't be an asshole. This is a reference of the opposite: when a drop of water means the world.

[@RadikAlice]

@@Throckmorton.Scribblemonger Complete opposite actually

[@kaitlyn__L]

@@Throckmorton.Scribblemonger I presume they meant a drop of water for a person in the desert, not just water in the desert in isolation :P

[@CORBARocks]

I love your channel, because I used some of the old kit you so diligently restore. Now a days who under 30 understands hardware flow control?!

[@no1leader135]

Cool video, 6502, 6522 and two 6551 and Linux. Perfetto.

[@SLLabsKamilion]

Just wanna point out, DB-25 actually has pinouts for two full serial ports and all the control lines. Most of the time the second port went unused; so it was reduced to the DB-9 we are more familiar with today.

[@DavidHembrow]

Interesting to see this. Back in the 80s i did a lot of typing on the keyboards of Televideo 910 & 925 terminals. Never saw a 950.

[@hawksights]

When manufacturers still had confidence in their customers

[@professorpwerrel]

For real, that manual is evidence that the right to repair has been eaten away at. For companies like Apple, their main argument is essentially that people are too stupid and will end up hurting themselves. So how much are they trying to say humanity has deteriorated since the 80s?

[@Okurka.]

These were sold to professionals.

[@EssenceofPureFlavor]

Yeah, I don't think that's really it as much as it is the intended market.

[@EngineerOfChaos]

@@Okurka. While true, even now things are much more sanitized to make it easy.

[@ByronGoodman]

Systems came with getty configured already. They typically would auto-discover the terminal, unless someone forced it (we did have scripts). They were very simple to setup. He is kinda doing things very backwards compared to how we did it in the 80s. inittab would spawn the serial sessions. I don't miss the days of abusing wall, and .plan files. I could never go back to writing code on one of these. You lived in emacs, and emacs was your 'screen', or 'tmux'. I still use emacs today, but it is painful over a serial port.

[@valeinikofff]

thank you! it immersed me in 1980s, totally (like, reliving the past).

[@esra_erimez]

I would love to get a vintage terminal like this and use a Raspberry Pi booting to serial. The irony is that how powerful and small the Pi is compared to the computers this terminal connected to when it was in its prime.

[@Sylvan_dB]

Could easily find room inside the terminal to mount the Pi. Just keep it away from the high voltage. With a bit more work you could use the Pi's built-in TTL serial direct to the terminal (bypassign the RS232 level conversion in the terminal) but you'd need to protect the Pi against the (probably) 5v TTL serial in the terminal.

[@samuraidriver4x4]

That's what Shelby did with another terminal. Works pretty good and there should be a video of it I think.

[@fuzzywzhe]

No you wouldn't want this. What would you do with it? A raspberry pi is as powerful as the Unix mainframe I was on in 1990. Why would you want to use this terminal? This terminal was designed for monochromatic graphical display. Did he even demonstrate that? If you want an "old style terminal", get a VT-220. That's just a 80x24 colum display (was it that? Something like that..) There was the VT-100 as well, but I hated working on them, they had lower resolution to draw the characters, much harder on your eyes. This terminal is not something you'd want to try to use. The backspace key, ALONE, makes is entirely frustrating to use. We had a bunch in college, but the only thing people used this for was to show pictures, then log off. I never once saw a person working on one. They were replaced by the NCD X terminals which were just dumb terminals that ran X11 in them, designed to be black and white - they were usable but I don't even know if they would be compatible with modern X11. You could, conceivably (?) run an NCD against a raspberry pi, but I'd check first. Those would be entirely usable if they are compatible with currently X11. And you don't want to go back to 1990 anyhow. You really don't. All of this stuff was neat at the time, but it's downright primitive today.

[@esra_erimez]

@@fuzzywzhe Yes. Yes, I would. Its the physical personification of putty

[@fuzzywzhe]

@@esra_erimez Why would anybody want to use putty? When I think about it, I'm not even certain this terminal is entirely compatible with the VT100 character escape sequences to allow you to run an editor like VI or Emacs on it. Maybe Ed. These sequences are necessary to position the cursor. Good lord, I'd never want to go back to stone knives and bear skins again. I used to be quite expert with the VT220. You could reprogram the font. Somebody used a program I wrote to make a video game, I think it was one of those pipeflow games. Interesting, somebody made BoulderDash on the machines, but they didn't use my program to do it, however I used my program to recode their version of BoulderDash to run on a VT100.

[@rochr4]

I am looking at my alacritty, tmux and gazillion of tools and hacks that I use to make it all comfortable and fast and actually irreplaceable with even more appreciation now, thanks! :)

[@PunchysGameRoom]

Great job cleaning that thing man, looks incredible!

[@devttyUSB0]

It seems fitting for me to comment on this video. ;) Terminal types are such a pain in the beehive. Even when you're running 'modern' terminal emulators it still causes pain and confusion if you're working on different systems through SSH. Great video, this! Thanks!

[@retsamyar]

heh for some reason idk if it was because i learned computers in the early 90s as a preteen or what but working through terminals and screens don't cause that much confusion. One of my fond memories is the old internet dialups came with unix shell accounts. That way you can get things fast to your shell from the internet and then slowly download later.

[@tali3san337]

Man I remember using screen when running an ISP (using modems) in the 90's. Fun times.

[@dustinsmous5413]

I have a Televideo 905 that I still use on a daily basis on my linux system! Televideo terminals are definitely built to last!

[@oqibidipo]

To stop bash inserting those ?2004 things add these lines to /etc/inputrc or ~/.inputrc $if term=tvi950 set enable-bracketed-paste off $endif

[@mikejetzer4155]

I wonder if whatever's setting your prompt (probably the PS1 variable; I don't use Bash that much) is just hard-coding some escape codes into it. If you know the termcap capability name (you know, "termcap" is short for "terminal capability"), you can use the "tput" command to generate the escape codes. For example, I might do "tput smso" ("set mode standout", which enables bold), print some text, and then do "tput rmso" ("remove mode standout"). I don't know what the default Bash config file(s) is doing to you; I set my PS1 in my .profile (plus I use Korn shell). I wonder if you neowhatever program inspects TERM or if it just hard-codes the escape codes. I would expect "man" to work properly. What happens if you do the equivalent of a man, such as "zcat /usr/share/man/man1/ls.1 | nroff -man | less -R"? I use Red Hat, so the location of your manpages could conceivably differ. So, you're gunzipping the "ls" manpage to stdout, running i through nroff with the "an" macros ("-m" means to use the indicate macro package, so it's just clever that it winds up being "-man"), and then piping that through "less". The "-R" option to less means to interpret, rather than display, any escape characters. The other thing is that your particular terminal might be some sort of variant (there were several tvi950-related options). You should look at your settings and/or EPROMs. Or, if there are sufficiently fiew of them, you could cycle through all of the tvi950* setting available until you find one that stops making a mess of your screen.

[@JdeBP]

Yes This is a common thing. People just hardwire control sequences in their shell rc and profile files, without even using tput.

[@mnoxman]

the widzard incantation for setting your 'back space' key is: "stty erase " also when you set your TERM you should export it. e.g. $ export TERM=tvi-950

[@ramsn1971]

Back in 2004 one of my clients had an old SCO Unix server with 16 dumb terminals connected via serial cable, in offices on a 2 story building. The clerks worked on a lot of medical data entry and a terminal was all they needed. My job was to convert all the stations to Windows XP with a telnet client instead. the funny thing is those clerks hated XP; they wanted their old dumb terminals back. They really could input a lot of data with those old terminals.

[@Sylvan_dB]

Those Televideo 950's were awesome terminals back in the day. Then Wyse finally one-upped them just as character terminals were on the way out.

[@Many_Sparrows]

These are my favourite type of video you make 👍🏻

[@retrozmachine1189]

termcaps are fun. I had to keep a suite of cobol programs working under linux for many years. For what ever reason the authors had hard coded it to work with SCO-ANSI only and the SCO-ANSI that was available for linux was incomplete at the time. Fortunately I had a copy of SCO, the suite was originally targetted at SCO, and was able to swipe the file from there.

[@Graham_Rule]

I'd forgotten about termcap and terminfo. Way back in the 1980's I supported an equivalent system for a locally developed operating system so knew far more than was sane about the escape sequences of the 30 or so terminal types we supported. I feel old.

[@paulstubbs7678]

Nice terminal, although not being VT100 is a problem these days. I've been looking for a terminal for ages, nothing in my neck of the woods. Serial is not that hard, you just have to get used to what DTE & DCE is all about, and how it was used back then, although I have a bit of an advantage, spending my early working years at a telco fixing terminals & modems.

[@rommix0]

> although not being VT100 is a problem these days. Anything not based on DEC terminals would be an issue. That's for sure.

[@GBS1043]

Wish I had a dollar for every VT100 I installed

[@deang5622]

DCE and DTE is simply terminology for each end of the serial link. It'a the control lines you need to get your head around and which particular ones are being used. For example, CTS, RTS. Or DTR, DSR. It's identifying which flow control mechanism is in use and which signal lines and how they behave.

[@paulstubbs7678]

@@deang5622 Yes that can be a real challenge, as these lines kind of get repurposed, and referring to older documentation on serial can lead you astray as the modern use quite often treats them as general purpose I/O lines, the only bit relevant sometimes is whether they are inputs or outputs.

[@retrozmachine1189]

Terminal printing isn't something I've even thought about for far too many years to mention. If done properly a long print job could be interleaved with normal user activities rather than occupying the terminal with printing for the whole duration of the job. At least in my experience printers were usually on their own separate serial port from the mux or host rather than the terminal.

[@xhausted110]

Try typing stty erase That usually works for me.

[@Ice_Karma]

So, while it's always a good idea to have TERM set correctly, some software out there doesn't actually use the terminfo library, and just has DEC VT escape sequences hard-coded. (I looked into the neofetch source, and it falls ito the hard-coded category. It looks like something in bash has an xterm escape sequence hard-coded, too, which turns an xterm feature called "bracketed paste mode" on.) Unfortunately, it's been a long time since it was mainstream to use anything but a DEC VT or an emulation of it. And personally... I don't really miss the days of terminal ecosystem diversity. Or the fun of maintaining code that has to work on a dozen different Unix flavours. Or the wide variety of microprocessors and hardware platforms. Most of the time, anyway. 😺

[@bloepje]

I had one of those (next to a lot of other terminals) for years on my many serial only systems. I actually wanted a 955, and all I got was this 950 and 920C. Bought them from school. I used to work on school on these. 96 people working at the same time on the same computer with 2MB ram, which was a lot. Doing "excel" and stuff. Never was a problem.

[@autobahnmensch]

this video is amazing... well done! I really learned something today :)

[@MegaManNeo]

screen was actually the first thing on my mind when you mentioned those character issues as I know it can fix those when set properly. It may have been struggling for you but me as a viewer, these old terminals look freaking awesome!

[@CoachCala]

Great video as always... But I think I speak for everyone when I ask if there's any news regarding the Data General Nova? 🤓

[@MrBrianms]

You could make an executable launch when you press the key. The screen memory sends to printer memory without the program appearing on the screen "echo off". I remember this program had to be in the DOS ready to run. It was great to magnify graphics onto the dot-matrix printer with simple multiplication. It was a BBC Model B with no print screen facility. A long long time ago...

[@ropersonline]

16:50: The Atari ST also beeped in acknowledgement of every keypress. Not the Ellen Feiss kind of beep-beep-beeps, but ye olde _"Roger, wilco, I have registered your keypress and will act accordingly, yes siree!"_ kind of beeps.

[@Psychlist1972]

I normally hate artificial keyclick sounds, but the beep on this one is dreamy :)

[@liamwatson5125]

I can’t get enough of that beeping either.

[@edgeeffect]

Nice terminal but looks like it really wants to be a VT100. Most terminals I used either had a VERY minimal status line at the top or no status line at all. But a lot of DOS or CP/M terminal emulators did have that heavy bold status line at the bottom... now I see where that styling came from: "if it's good enough for Televideo, it's good enough for us".

[@choppergirl]

Yep, my vast collection is stored in a barn. No other place to store hundreds of antique computers nobody loves. My favorite 8bit antiques I moved into an old house trailer so they are a little bit better off. But tons of 68k / powerpc macs and 486 / Pentium PCs in a barn. Picks up the Model M I'm typing on... yep... empty speaker grill. The only terminal I have in my collection is a Heathkit.

[@hawksights]

I'm pretty sure, you could simply map the backspace key to CTRL+H in the screenrc

[@ppokorny99]

Or stty

[@anvz6]

As I remember. Printing on Unix is simple. You send a command to the terminal (^P in general) and it instructs the terminal to forward everything it receives in serial port, to printer port. ^N ends this behavior and resumes the normal operation. Then. The wen you print a file, rh spool program formats the output and sends it to a script indicating the destination printer. This script knows that this printer is attached to some terminal and knows it's serial port. So it sends ^P to this serial port followed by the print data and a ^N. This means you can send print jobs to any slave printer on any terminal. The only problem is that during the print the screen is frozen.

[@Eddies_Bra-att-ha-grejer]

Even modern motherboards generally have serial ports, but only as a header. You can buy a PCI bracket to pull it out on the back.

[@franksemi_modular]

May I suggest making a Linux installation with a teletyper as the only output 😃

[@scooter4196]

We used IBM TTYs for interacting with AIX machines. Prior to that we had a mainframe.

[@branscombe_]

my ibm pc jr had a telecommunications disk with a modem back in 1988

[@MrCoolSponge]

I understand that you don't have a sink in your office but I don't understand why you don't use rubbing alcohol to help clean these old dirty products It works extremely well as a wet cleaning agent that can be used without the need for a sink Maybe try getting some 70 - 90 % rubbing alcohol and putting it in one of those small plastic sprits bottle (the ones you squeeze like a bottle of Windex). Use paper towels and Q-tips to wipe it down

[@MrCoolSponge]

@@martinr1834 >He's a young man, why would you expect him to have any experience with cleaning? Is this meant to imply I'm a not a man or that I'm not young?

[@oliverw.douglas285]

Reminds me of the DEC VT100 Series of Terminals. Very similar in many regards.

[@Sylvan_dB]

Serial is far worse that you describe. 😅 There is also Data Terminal Equipment (DTE, the "standard" for terminals) and Data Communications Equipment (DCE, the "standard" for modems). In theory you could connect a DTE and a DCE directly. In reality, never. The first "tech" job I was paid for, was helping a 3rd party company to run serial cables thru my father's office for his first computer system (S100 chassis, multiple terminals selected with a switch, two printers - a dot matrix and a daisy wheel). I was hanging out in Dad's office after school, and as soon as the crew running the wires found out I could solder and read a pinout diagram, I was recruited. We ran the cables, and soldered the appropriate 25 pin connectors on the ends with the wires crossed as needed. This means not only matching Tx and Rx, but also the hardware handshaking lines (almost possible to ignore on the terminals if you run a slow enough baud rate, but critical on the printers).

[@cedwardmassey]

15:16 you may confuse people by saying that the monitor has an 80×24 column display. To avoid potential confusion, you could call the horizontal "columns" "rows" instead.

[@maxpolaris99]

A null modem! I have one somewhere, and it's not with my modern collection of digital adapters and converters. Must be upstairs with the retro stuff.

[@definitelycasualpcs8789]

Oddly I have a televideo 905 that I've been wanting to get working. But no idea how to connect to a bbs or telnet or even to a pc. Instructions unclear on Google lol

[@herdware]

What a sad state of linux affairs that programs don't respect the terminal capabilities anymore. :(

[@JdeBP]

It has over the years been difficult getting updated terminfo entries into Linux-based operating systems (albeit that M. Dickey is very responsive to people providing stuff, in my experience; it's getting those updates through the distribution maintainers that seems to be the bottleneck) that even provide things like information about colour, so there's a decades-long tradition of just hardwiring XTerm colour control sequences.

[@Matthamatic]

Cat goes μ

[@yofreak666]

Someone is playing factorio, nice ;)

[@billmiller4800]

The screen util is removing all escape characters, input and output. If you can turn off the colour in the terminal (like LS_COLORS for Ls), the terminal will work fine without screen.

[@maxpolaris99]

Digital Archaeology is very cool!

[@shmehfleh3115]

Also, in almost all cases, control-H works as a backspace. It even works in Apple II Basic.

[@johndododoe1411]

That's because backspace is ASCII character 8, so on anything resembling a serial terminal, it's the same as sending the 8th control code via ctrl-H . Similarly delete is character 127 (which makes a lot more sense when using 7-hole punched tape to write teletype messages to be sent directly to another terminal over a pay-per-minute phone line. The huge problem is that someone in the early days of Linux swapped the two ASCII codes and insisted their nonsense was the correct behavior for the local Linux console.

[@Jerrec]

Using serial terminals and printers is MUCH easier in FreeBSD then it is in Linux. I am a Linux guy and dont use FreeBSD much, but I love it for the fact that it is still Unix! :-) FreeBSD's /etc/ttys is so much easier to configure then agetty and the services it needs if you want something "special".

[@EngineerOfChaos]

Urgh, your talk about serial adapters remind me of work. My entire last two weeks of work were all about interfacing USB with RS-232 and RS-232 with RS-485 and all these adapters and stuff are all part of the horrible headaches involved.

[@mikejetzer4155]

I think you can blame IBM for some of the gender issues. In the beginning, pretty much every machine had female RS-232 connectors (the real, 25-pin, ones). When IBM decided to cheap out on their original PC and use a DB-25 instead of a Centronics-36 connector for its parallel ports, it decided to use female DB-25s for parallel and male DB-25s for serial. (I had an AT&T 3B1/Unix PC, which had an honest-to-goodness Centronics-36 on it for its printer port.) If not for that, I'd expect that the USB/serial adapters would have male connectors. They'd also be DB-25s, as I believe that IBM also popularized the DB-9 connector for serial.

[@zeusde86]

I'm pretty convinced, that you can avoid agetty completely and use screen directly, as it accepts tty-devices as inputs just like `screen /dev/ttyUSB0` (plus terminal-mode options of course). I always use it like this when using serial-output from microcontrollers and such. beside that, you can configure screen to not show it's start-screen, that you have to bypass by pressing enter (which is default on only some distros).

[@Okurka.]

7:41 That's not a u. 13:03 That's not an RJ series connector. 18:03 That's not DB-9.

[@dave7244]

When you opened it up. TBH it didn't look too bad. Sure there was a lot of dust and dirt. But there didn't seem to be any corrosion which would be my biggest worry with a piece of equpment kept in less than Ideal conditions.

[@JanBruunAndersen]

I very much doubt that Bash itself emits (colour) control codes. However if the person behind the keyboard have blindly configured a $PS1 variable (prompt string) or a $PROMPT_COMMAND without paying attention to the terminal type, then Bash could do anything, including sending weird escape sequences/colour codes to the innocent terminal. And of course, you have utilities like 'ls' and 'grep' that tries to be helpful and colourise their own output unless you explicitly turns it off. But at least those utilities should be smart enough to read said escape characters from termlib and do it right. As we used to say: PEBCK - Problem exists between chair and keyboard.

[@IkarusKommt]

BASH doesn't emit color codes, it emits the paste delimiter code specific to Linux consoles. It protects terminal emulator from malicious pastes.

[@JanBruunAndersen]

@@IkarusKommt - I don't think you know what you are talking about.

[@IkarusKommt]

@@JanBruunAndersen DECSET 2004 - Enable bracketed paste mode.

[@JanBruunAndersen]

@@IkarusKommt - I could be wrong (but I doubt it as I am usually right), but I do not see what relevance this DECSET 2004 thing has with Bash. It seems like something that is only of concern to terminals and terminal emulators, not with whatever command interpreter or whatnot that is talking to the terminal.

[@Hiraghm]

I ssh onto my (linux) phone from my linux desktop and vice versa a lot, actually.

[@HelloKittyFanMan]

"This thing _first_ came out in 1980..." Oh? When are the supposed "other times" that it "also came out" during?

[@davidmoore4567]

To change the back space character try using stty erase. Hopefully the commands for clear, vi and Emacs should work perfect as these will make use of the term variable, make sure display is unset. I did not use this model but the 925 with a Spiderport that used to connect to both Sun OS and Primos systems when I was studying. Obviously I preferred the Prime Pt220 and Dec Vt320 and vt340 terminals to this one. If you even need to connect to the Serial port of an old Sun system the default is 9600, 7 bits, even parity with xon/xoff and if connected to the console do not press the break key if you have one as that will bring up the open boot or old mode prompts depending on the setting

[@JimmyCall]

I can recall the terminals in past workplaces had config pages. Can't remember how to display them. Maybe on more modern terminal units and brands.

[@petersnape1537]

back in the 70's and 80's we used to say that RS232 was just another name for Murphy's Law

[@hypercube33]

Ya'll need a dishwasher in your office to wash electronics. (Just dont use dishwasher soap since it usually has abrasives and bleach which is no good)

[@zaxchannel2834]

It would be pretty cool to have a sort of CLI only set up for this

[@abcpea]

i think FreeBSD should have better terminal support

[@JdeBP]

In fairness, the likely culprits are nothing to do with the operating system: hardwired control sequences in a shell prompt set by the shell's rc or profile file, and grotty deciding to do colour for some reason. One gets such things happening on FreeBSD too, alas.

[@amorphousblob2721]

It's likely that the TVI-950 either doesn't support highlighting and underlining, or that there's no information in the Terminfo file to tell Screen how to do it. Highlighting and underlining worked fine on my NCR 7912 through Screen, and also directly with the majority of programs. But that was back in the 1990s, when only a few noobs had adopted the attitude that only software terminal emulators mattered. If "man" showed fragments of ANSI sequences back then, it would've been regarded as a bug.

[@furripupau]

Kaypros have keypress beeps. You have to turn off the beeps in the config program. I never have because it's not that annoying to me (the piezo speaker being buried inside the metal cased keyboard is barely audible unless you're working in dead quiet).

[@maxsteffens]

you need to analyze the serial communication identifying the characters that need to be replaced, for a correct communication, with arduino

[@frogz]

386 views May 13, 2023 .....i feel somewhat special for getting this number

[@MrFungi69]

yeah.. you so special.

[@frogz]

@@MrFungi69 don't be angry, we can't all be spechul

[@Mike-mu7tk]

Control-H is the "escape code" that does delete. If your terminal isn't mapped properly. That usually works

[@JdeBP]

One really cannot call something an "escape code" if there's no ESC in it. It is a _control character_ . (-:

[@asagoodfriend]

Yo Shelby's working on a secret Atari Project! :0

[@VanceStrickland]

To get your backspace working again in screen, try "stty erase ^?" or "stty erase ^H" (I don't remember which is BS vs DEL - it's been a long time). Also in the OLD days with getty (pre-Linux days), on some systems you had to put in a termcap entry for the terminal and then "compile" it into a terminfo file that was actually used. Don't know how Linux does it, this was in the days of BSD 4 using termcap and Sytem III/System V using terminfo (again if I remember correctly). It's been literally decades.

[@Ice_Karma]

The `stty` command should help you with the backspace and delete thing.

[@realdragonrude]

The best times when companies outright told you to take it apart and check everything

[@Okurka.]

Best times? You want to take apart your new smartphone and check everything before you can use it?

[@oliverer3]

​@@Okurka. If it wasn't glued together and it voided the warranty I'd totally do this xD

[@Okurka.]

@@oliverer3 Opening a device doesn't void the warranty.

[@douro20]

Bitsavers has the firmware for these terminals.

[@nticompass]

My media server uses a motherboard that has a built-in serial port, so I have that configured to run an agetty on it at boot. Side-note that motherboard actually lets you enable serial in the BIOS! You can access the BIOS screen via serial! :O Anyway, I set up a special "serial" user on the server, so when you use a terminal and login, you get a menu asking you your TERM type 🙂

[@martheri]

good show, bro. keep it up.

[@yjk_ch]

Yeah... Many programs just don't support anything other than what typical Linux terminal emulator uses. I would imagine ncurses would handle escape codes correctly, but others would hard-code or use library that hard-codes escape codes. Honestly, even I don't really think about those old terminals when writing programs. Though I also do not use any escape codes either, to make redirecting output to file easier without relying on third-party library.