back to article A paper clip, a spool of phone wire and a recalcitrant RS-232 line: Going MacGyver in the wonderful world of hotel IT

Come with us to the 1980s, when computers cost proper money and RS-232 ruled the roost in another edition of Register reader recollections courtesy of On Call. Today's tale comes from "Jeff", who spent a good portion of the decade that gave us The A-Team, Knight Rider and the IBM PC working in the hotel IT business. "RS-232 …

  1. tip pc Silver badge
    Facepalm

    Proper lash up

    Probably still there.

    1. Admiral Grace Hopper Silver badge
      Windows

      Re: Proper lash up

      The "6 months - tops" lash-up code that I wrote in 1992 is still running I hear. I wonder what happened to the project that it was a stop-gap for?

      1. jake Silver badge

        Re: Proper lash up

        You're probably using the lash-up that I put together in 4.1BSD (now called 4.1aBSD) for part of the TCP/IP stack to be included in 4.2BSD[0]. It was supposed to be one of those "just get us through the demo, dammit" hacks. I can't remember exactly when it was included, but I was working on it over Christmas/NewYears 1981.

        [0] Just to cut the usual pack of idiots putting words into my mouth off at the socks, no, I didn't write the whole stack. That's why I said "part of". It was only about 120 lines of C in total.

      2. Dave 32

        Re: Proper lash up

        Ah, yes, the "temporary" fix. Back in the early 1990s, I encountered a comment of the form:

        /* The following two lines are a temporary fix for the xxx problem. Sept. 1971 */

        I decided that I wasn't about to touch temporary code which was legally old enough to drink. For that matter, to the best of my knowledge, that code is still in place, and still running!

        Dave

        1. Nugry Horace

          Re: Proper lash up

          When maintaining software I've seen TODO messages reading "Temporary fix we need to do this properly later". Needless to say the person who left the message has long since retired and no-one else can guess what he meant by it.

          1. Phil Endecott Silver badge

            Re: Proper lash up

            The other common possibility, in my experience, is that it WAS fixed properly about 3 days later but the comment was left unintentionally...

      3. Blackjack Silver badge

        Re: Proper lash up

        They had to hire someone to update the COBOL it was running in?

      4. Alan Brown Silver badge

        Re: Proper lash up

        "The "6 months - tops" lash-up code that I wrote in 1992 is still running I hear."

        The "6 months - tops" Post Office radio hut installed (in 1946) at one site I worked at was removed in 1988.

        I won't say demollished. When the internal ironwork holding the racks up was dismantled sometime after the new building was finally commissioned in 1986, the walls and roof literally fell off.

        1. Kobus Botes

          Re: Proper lash up

          @Alan Brown

          The temporary fibre cement (probably asbestos) classrooms that we moved into when we started High school in 1971 are still in use as I write.

          The classrooms were slated to be demolished in 1973/74 (if I remember correctly) once the school was split into two single language schools - this eventually only happened in 1977/78.

    2. big_D Silver badge
      Facepalm

      Re: Proper lash up

      That is the problem. You get a temporary, Heath Robinson solution in place to tide the user over until they can get the problem fixed.

      At least, that is you interpretation.

      On the other hand, the user just sees that the problem has been resolved, end of story.

      1. Doctor Syntax Silver badge

        Re: Proper lash up

        "You get a temporary, Heath Robinson solution in place to tide the user over until they can get the problem fixed."

        Some of the worst Heath Robinson efforts I've seen were intended to be permanent.

        1. Alan Brown Silver badge

          Re: Proper lash up

          "Some of the worst Heath Robinson efforts I've seen were intended to be permanent."

          Yup and I have a reputation for doing my nut, mainly because of twats trying to inflict them on me (as the person who has to put up with them) without actually consulting me on any part of them.

          Or worse, listening to what I have to say and then coming back with something completely unsuitable and a HSE hazard to boot.

          They called it obnoxious behaviour - I just threatened to get HSE inspectors in afterwards.

      2. JeffB

        Re: Proper lash up

        Much later than RS232, but still a Heath Robinson affair...

        A cabling lash-up that I have used a few times to get users out of deep do do involves a broken USB memory stick and a length of ribbon cable. A cheap USB stick is in the front port of a PC, which is housed in a lectern/stand such that the USB is sticking out beyond the stand. Tutor turns around and knocks said USB with their posterior, causing the body to depart from the connector.

        Said tutor comes crying to me with the parts in their hands saying that all their teaching materials are on there and they don't have a backup!! Close inspection identifies sufficient copper track to be able to solder to, but the mount points for the connector are damaged, so it cannot be re-attached normally. Enter a length of ribbon cable, extract 4 strands, strip the ends and solder into place, all data now accessible, cue fawning 'Thank Yous' from tutor.

        How long they carried on with this lash-up before transferring the data to either another stick or network storage I'll never know...

        1. Daedalus Silver badge

          Re: Proper lash up

          Common use machines should always use pigtail extension leads for USB, and audio if appropriate. Prevents "mashing it home" from compromising the onboard sockets, not to mention butt bumps.

          1. Anonymous Coward
            Anonymous Coward

            Re: Common use machines should always use pigtail extension leads for USB

            That sounds like a good idea.

            I was visiting an aunt and she wanted me to see if I could plug in her mouse. The USB cable would not go in. Finally saw a piece of black plastic had broken off of a previous cable. Luckily it came out easy enough as my tools were 90 miles away.

            1. Blackjack Silver badge

              Re: Common use machines should always use pigtail extension leads for USB

              USB Mouses broke so easily I had a box with about a dozen of them. They lasted a few years before I was down to two. Those two still work but my CPU has a PS2 port so that's probably only because I haven't used them much. I dread the day I have to replace it and find that the new CPU has no PS2 ports.

              The problem is usually that the users tend to use the first USB port they see, aka one in front of the CPU, so the cable tends to suffer a lot more reducing the durability of the USB mouse a whole lot.

              1. Glen 1 Silver badge
                Paris Hilton

                Re: Common use machines should always use pigtail extension leads for USB

                "CPU has a PS2 port"

                " first USB port they see, aka one in front of the CPU"

                *eye twitch*

                1. Chris 239

                  Re: Common use machines should always use pigtail extension leads for USB

                  Yeah, I had that twitch too but at least Blackjack didn't call it the "hard disk" which both my mother and mother-in-law do.

              2. phuzz Silver badge

                Re: Common use machines should always use pigtail extension leads for USB

                Should have bought a Microsoft Intellimouse back in the early 2000's, those things last forever. I still have one at work that gets hauled out when I need a spare (they came with a USB-PS2 adaptor in the box, but I don't remember seeing a computer with a PS2 port for years).

                1. Wommit

                  Re: Common use machines should always use pigtail extension leads for USB

                  phuzz,

                  Maybe not on business machines, but gamers just love PS2.

                  USB is a polled solution, your usb device might have to wait, ohh, a millisecond or two. PS2 however is interrupt driven. much faster. :)

                  1. Anonymous Coward
                    Anonymous Coward

                    Re: Common use machines should always use pigtail extension leads for USB

                    I've just built three gaming PCs from brand new components, and was slightly amused to see the motherboards still had a PS2 connector. They were gaming-focused motherboards, so that's exactly why. All of the gaming mice in our house are USB though; I haven't dug into it yet but I suspect the polling rate on them is a lot more frequent than 1-2ms.

                2. jake Silver badge

                  Re: Common use machines should always use pigtail extension leads for USB

                  I still own and operate half a dozen of Microsoft's 1987 "Dove Soap" mouses/meese/whatever. To my hand, they are the best two button mouse ever made. It's pretty sad, when you think about it, that the world's largest software company has only made one decent product in it's entire history ... and it's a bit of peripheral hardware for an interface that has been depreciated.

                  1. phuzz Silver badge
                    Gimp

                    Re: Common use machines should always use pigtail extension leads for USB

                    To be fair, Microsoft have produced some pretty good hardware over the years. The intellimouse has gone through various versions over the years, and all the ones I've tried have been as good as the first ones. Their ergonomic keyboards seem to be well liked by people who are in to that sort of thing. They've invented a design for a battery holder for AA batteries which allows them to be inserted either way around. And at the end of the day, most of their hardware is relatively inexpensive.

                    If they never made software they'd probably be a well regarded company.

          2. Alan Brown Silver badge

            Re: Proper lash up

            "...always use pigtail extension leads for USB"

            Not just USB

            I once caught a tech spitting into Serial connectors to make them plug more easily

            1. Anonymous Coward
              Anonymous Coward

              Re: Proper lash up

              Wait, that was wrong?

              :)

              1. David 132 Silver badge
                Windows

                Re: Proper lash up

                Yes. Saliva is electrically conductive. You’re instead supposed to rub the connector vigorously over your forehead and scalp, to get plenty of nice lubricating grease on it. That will help it slide into the socket.

                Icon, for obvious reasons.

                1. jake Silver badge

                  Re: Proper lash up

                  Try the side of your nose for the grease. Works for the ferrules on a couple of my ancient two-piece fly rods (tech-tip from my Grandfather).

                  1. Tim99 Silver badge

                    Re: Proper lash up

                    Yep, it worked on a Hardy Perfection 9ft that I had. The "permanent” fix was to rub the male ferrule with 6B pencil lead.

                    1. jake Silver badge

                      Re: Proper lash up

                      "The "permanent” fix was to rub the male ferrule with 6B pencil lead."

                      Graphite wasn't an option ... we were often fishing for Steelhead in salt water and needed the grease for a little protection from corrosion.

                2. MrNigel

                  Re: Proper lash up

                  Reminds me of when I worked for 'British Relay Special Services Division' back in the 70's. We did loads of 100v line stuff in Central London and part of my 'initiation' was being forced to use my tongue to see if a circuit was live. Back when 'men were men' and snowflakes were something you only saw in February...

            2. Montreal Sean

              Re: Proper lash up

              "I once caught a tech spitting into Serial connectors to make them plug more easily"

              Maybe he should work on his foreplay a bit more...

            3. zuckzuckgo Bronze badge

              Re: Proper lash up

              The current procedure is to soak your USB devices in soapy water while singing "Happy Birthday" twice. Gets rid of all those nasty malware viruses.

          3. Robert Carnegie Silver badge

            Pigtail extension lead

            What I don't know is where to get short extension leads like that... but I last bought some when Maplin shops closed down, and I know that Maplin was last seen as a reborn online business so......?

            In general, you also can use a USB hub made with a short cord as an extender, but it doesn't always suit.

            I approve the method to avoid wear and tear when devices are frequently plugged and unplugged, for instance USB "thumb drives" as discussed. Ideally, I think, you'd have one port adapter belonging to the thumb drive, and another one belonging to the PC, i.e. drive -> pigtail -> pigtail -> PC. As it is, even with careful use, I have thumb drives that need to be wiggled in a port - usually on an extension lead - to find a connectlion. The two-pigtails idea is that the ports on your expensive devices themselves are seldom or never plugged and unplugged.

    3. Jon Blund

      Re: Proper lash up

      Nothing is as permanent as a temporary solution.

      1. A.P. Veening Silver badge

        Re: Proper lash up

        Except for a temporary tax hike.

        1. MiguelC Silver badge

          Re: Proper lash up

          Where I live, a temporary viaduct over the railway was built in the early 70's to allow easy access to the dockyards. It's still in use and is now commonly referenced as the "Interim Overpass". Maybe one day it will be renamed to "Permanent Overpass" and everything will be fine.

          1. A.P. Veening Silver badge

            Re: Proper lash up

            The town I grew up in has a tower of which the literal translation of the name into English is "The New Tower". It is only a bit more than 7 centuries old and slightly younger than the nearby "The New Market".

            1. Norm DePlume

              Re: Proper lash up

              Newcastle-upon-Tyne in the UK is named for the castle built in 1080.

              1. Terry 6 Silver badge

                Re: Proper lash up

                The "New Forest".

                When my kids were on Guide Camp there donkeys' years ago I asked them if they'd seen the old one as well.

                1. Daedalus Silver badge

                  Re: Proper lash up

                  Reminds me of when we swam in the public baths' "New Pool". It was new in 1935, the Old Pool being Victorian.

              2. Evil Auditor Silver badge

                Re: Proper lash up

                Still better to name something "new" which at least is relative. When I joined the company in 2007 we had an ongoing (far from finished and later to be aborted) project for the replacement of the core system called Sys2005 for its intended go-live date in that year.

              3. oldfartuk

                Re: Proper lash up

                The small village i grew up in, in the 1960's, had a family who lived at one end who were always creferred to as "The New Family". Apparantly they had moved to the village just before WW1.

                1. silks

                  Re: Proper lash up

                  This is a local shop for local people, there's nothing for your here!

              4. G.Y.

                700BC Re: Proper lash up

                Carthage is Poencian/Punic for "new town". Founded 700BC+-

                Ditto (mutatis mutandis) Novgorod

              5. Alan W. Rateliff, II
                FAIL

                Re: Proper lash up

                castle built in 1080.

                I was going to make a joke about the castle in 1080 replacing the one in 720... but never mind, my heart just isn't in it.

                1. Aussie Doc Bronze badge
                  Pint

                  Re: Proper lash up

                  Does sound like the makings of a New Year's Resolution joke, though, so have one on me.

              6. Andy A
                FAIL

                Re: Proper lash up

                The town where I live had for many years a sign near one end of the main street announcing "NEW ROUNDABOUT AHEAD".

                It was removed about 6 months after the roundabout was replaced by a set of traffic lights.

            2. silks

              Re: Proper lash up

              Hate it when things are named "new" as the name dates quite quickly.

            3. big_D Silver badge

              Re: Proper lash up

              The town where one of my nieces lives in Germany has "Old Newtown" and "Newtown" as suburbs... (Alte Neustadt and Neustatd).

            4. kiwimuso
              Meh

              Re: Proper lash up

              The church at Hever Castle where Queen Elizabeth I's father Thomas Boleyn is buried is called the new church.

              It was built in 950!!!

          2. john bertelsen

            Re: Proper lash up

            At the company I just retired from there are two supply cabinets in the office. The keys are labelled "New Supply Cabinet" and "Old Supply Cabinet".

            Both were present when I started in 1978, and they are both old now.

          3. iainr

            Re: Proper lash up

            If it does it'll get knocked down the following year.

          4. Lilolefrostback

            Re: Proper lash up

            If your government works like ours, it will be renamed the Permanent Overpass the day AFTER plans are announced to remove it.

          5. jonathan keith Silver badge

            Re: Proper lash up

            It's a racing certainty that two days after being renamed "Permanent Overpass" the whole thing will disintegrate into dust.

      2. Anonymous Coward
        Anonymous Coward

        Re: Proper lash up

        The whole expression is "The temporary becomes permanent, the permanent turns out to need replacement."

      3. Donn Bly

        Re: Proper lash up

        Nothing is more permanent than a temporary solution THAT WORKS

      4. Anonymous Coward
        Anonymous Coward

        Re: Proper lash up

        We have leased printers with stickers that have TAN numbers printed on them.

        TAN = "Temporary Asset Number", that was at least three years and a company name change ago!

      5. James Wilson

        Re: Proper lash up

        Like the 'temporary' speed restriction over the weak bridge on the A335. The signs put up for it suggest the expectation is that it will be in place for a while. Been a few years already I think (I haven't counted).

    4. Anonymous Coward
      Anonymous Coward

      Re: Proper lash up

      Do a search for "TEMPORARY, I HOPE HOPE HOPE". Or see this excellent poetic commentary on it.

      http://www.thecodelesscode.com/case/234

      1. A.P. Veening Silver badge
        Pint

        Re: Proper lash up

        That deserves more than the one upvote I can give you, have a ===>

      2. WonkoTheSane
        Thumb Up

        Re: Proper lash up

        Codeless Code is full of BOFH-level wisdom for the ages!

      3. Version 1.0 Silver badge
        Thumb Up

        Re: Proper lash up

        And we continually see commentards here saying the comments are not needed in code because any competent programmer can always just read the code.

        1. jake Silver badge

          Re: Proper lash up

          I think it's pretty safe to say that any commentard who seriously claims comments in code are unnecessary can be summarily ignored with no collateral damage.

          The only issue is figuring out who is lying when they retroactively claim to be joking ...

        2. dajames Silver badge

          Re: Proper lash up

          ... we continually see commentards here saying the comments are not needed in code because any competent programmer can always just read the code.

          Aye, the code tells you what it does (which may or may not be the right thing) ... the comments tell you what it was meant to do (which may or may not still be relevant).

          The sad thing is ... nobody knows why it does it!

        3. Allan George Dyer Silver badge
          Windows

          Re: Proper lash up

          Comments are there to confuse and misdirect the unwary.

          It's called job security.

        4. Nick Ryan Silver badge

          Re: Proper lash up

          A place that I worked at in the early 1990s trialled automatic system documenting through extracting the comments from the source files. They gave up very quickly when they found what the developers had written in the comments...

        5. Old Used Programmer

          Re: Proper lash up

          I did once make a comment telling anyone in the future not to muck about with that section of code unless they actually understood what it was doing and how it was doing it.

        6. robn
          Headmaster

          Re: Proper lash up

          I once wrote 25-27 lines of comments to document the usage of a single assembler instruction. And actually, it only pertained to one register operand for that instruction.

    5. JimboSmith Silver badge

      Re: Proper lash up

      I once received a call from a cousin about the installation of SKY. They were thinking of turning the attic room at the top of a very tall house into a home office. They had therefore had BT there to install a new phone line to use with the modem. the plan was to have a Sky box up there for watching the Cricket/Rugby etc. However by the time the bloke arrived to install Sky this had all changed. They wanted to use the attic room for something else and the home office would be the small room next to the living/tv room. The second box was going into the bedroom now as it wasn't needed in the home office. However the Sky installer having originally insisted that the Sky Digital box had to be connected to a phone line before he could leave. He was insistent on that and my exasperated cousin had no intention of letting him hook it up to their normal phone line.

      So in deperation she called me and asked what to do. She explained that the master soxket (and the only socket) for the modem phone line was at the top of the house. she further explained that the only socket on the ground floor was in the kitchen and they had a DECT phone linked to the kitchen to provide coverage in the tv room. I asked if he'd requested the Sky Digital smartcards yet and she said no. He was far more interested in the lack of phone line apparently. So I told her to tell him that they hadn't arrived yet and that her cousin would come round and complete the installation. I said to mention that I worked for a broadcaster and had engineer in my job title. She asked me to speak to him and I explained exactly that. He wasn't very happy about this but wasn't about to hang around waiting for the post to arrive. So she was left with everything installed except the Sky Digital Boxes.

      I went round that evening with several of my longest phone extension cables, various other tools, 20m of christmas ribbon and a promise of dinner. She explained that they wanted to put the modem into the office but the line was in the attic. Helpfully following renovations they had ripped out part of the central heating to start again. There was a couple of close knit holes running through each floor from the top to the bottom of the house. So using the Christmas ribbbon I pulled the niw joined extension cables from the bottom to the top of the house through one of these holes. Stopping on the way to connect and complete the installation of the bedroom box. I secured the cable in the attic with a couple fo cable ties nailed to the skirting. The living room box was only just reachable with the cables Ihad with me but I did manage to complete the installation there too.

      Over dinner I told them that the cable lash up was only temporary and not very secure. I said they'd want either to get BT back ASAP to move the master socket or put a propper extension in. The incoming cable was direct from the pole outside to the attic so I couldn't touch that. Also I wasn't going to do DIY work for them. I then propmtly forgot all about it until a few years later I was round one day for a party. I asked if I could have my cables back and was told sadly not they still needed them. Puzzled I asked why and the said they were still using them for the internet. They'd had to gaffer tape the joins together as they had suffered over the years and some small child pulling on them. They were now using this for ADSL believe it or not and and were quite happy with it. They did eventually get someone round probably BT/Openreach to do the work rewiring.

    6. Anonymous Coward
      Anonymous Coward

      Re: Proper lash up

      One of our customers decided several years ago that they needed a system so that customers could order online and pick up their order in store.

      This was bodged together quickly, but because most customers didn't use it, the various issues were ignored and the support staff have got used to having to restart it manually, every week or so.

      Fast forward to now, their shops are only allowed to do click and collect, and they're getting four times the traffic, and most of it is heading at this slightly wonky component...

      Glad I'm not in that support team ;)

      1. Robert Carnegie Silver badge

        Re: Proper lash up

        Is this a UK retailer whose customers can generally get their groceries in at the same time? What with $RETAILER stand alone shops being closed entirely during coronavirus. They also do business inside $GROCER stores. A retailer/grocer operational synergy.

        The one that I'm thinking of has annoyed me a bit because goods also must be paid for online before you go to $GROCER and queue up. Not "collect, pay". Or paid for online while you queue up, things being as they are. The thing is, I've used most of my credit card limit... and I don't wnat to do online purchasing without it.

        I assumed the limitation was a deliberate decision, but you have me wondering.

  2. Woza
    Joke

    Truely

    Swept under the rug!

    1. macjules Silver badge
      Alert

      Re: Truely

      The bane of my existence: BT Red Care burglar alarm systems.

      Around 1998 a very bright spark decided that my IT department should have a Redcare burglar alarm installed, just in case, you know, a very clever thief managed to get through the armed security at King Charles Street, into a government department that had more armed police in the reception area, got down into the basement (onboarding for new staff involved escorting them to reception until they knew how to find their way along the maze of basement corridors) and found their way to a security pass-blocked door.

      BT duly arrived and installed the RedCare line and it worked. Just as the engineer was about to leave someone mentioned that the emergency external lines had all gone down.

      Cue: "Before you go Mr BT Engineer what did you just do?" and the sheepish response that he could not find a spare line to use, so he opened the trunking, sliced though the bunch of external telephone lines, bar one he used for RedCare, and closed the trunking. I asked him if he would mind fixing the lines he had "accidentally" severed ... "since one of those lines is a direct link to a government security centre and we might need it if there was something petty .. like a national emergency".

      The BT engineer apparently filed a report that he felt that he had been intimidated and not allowed to leave the building. The reality was that I refused to allow someone to escort him out of the building and he must have spent some time wandering the basement corridors before being tracked down by security and escorted out of the building.

      1. Anonymous Coward
        Anonymous Coward

        Re: Truely

        Shirley you just needed to put up a sign that said "beware the leapord".

        1. ricardian

          Re: Truely

          Why did I read "beware the leapord" as "beware the teapot"?

          It was VERY early in the morning.

      2. Martin an gof Silver badge

        Re: Truely

        I think this was part of the standard training for BT engineers. Working at a radio station we knew some excellent engineers at BT who were quite happy to take a direct call at their racks (don't ask how we obtained that number), but we also met several who were "just doing their jobs".

        Like the one who was installing temporary telephone lines for international commentators at the nearby National Stadium, couldn't find a spare pair and re-used one that didn't have 50V (POTS) or 70V (ISDN) on it, reasoning that it was out of use, rather than actually - you know - looking at the schedule on the door of the cabinet.

        Needless to say, that "unused" line was our permanent EPS85 analogue line to the stadium and as you may have guessed there was a big international coming up.

        Fortunately our kit in the stands shorted the incoming line to the outgoing line when the microphone was not plugged in, and we fed programme down the line by default. Checking the line at our end revealed silence and we were able to get the thing fixed before the match.

        One step further was the pair sat in the road directly outside our main entrance, listening to our AM service on their portable radio, who had been tasked with replacing a length of cable, but had no idea what was on it - businesses in that street had had generic letters about some phone lines being affected for a short period.

        Our FM service used starquad cable which is easily identified in a duct, but the AM service was in a normal phone bundle. You can guess the rest, but at least they owned up very quickly and got the thing lashed together almost as quickly, before doing a proper repair. It's a long time ago but I think they even had some light banter with the bloke on-air when things were back.

        M.

        1. phuzz Silver badge

          Re: Truely

          A few years back I was working at a company that had an SDSL installed.

          One day it stopped working. After escalating through our ISP, we eventually found out that we were one of only three SDSL connections in the southwest, and that a 'helpful' BT engineer had been working nearby, seen the wiring for our circuit and though to themselves "that ADSL is wrongly wired, I will be helpful and fix it", which of course utterly banjaxed it.

          It took several days to find an engineer that understood SDSL to re-wire us.

  3. TonyJ Silver badge

    Back in the very early 90's...

    ...a colleague and I used to wire all the RS232 connected terminals in, as well as cable any new phone extensions into the PBX.

    I remember we had great fun using only green wires wherever we could get away with it, knowing that anyone following us in a few years would be fuming at the lack of additional colours.This was reserved mostly for where we had to put connectors through walls or make adapters of course - we had no choice in the colour of the cores in the main cable.

    I do remember once wiring in about a dozen new phones and of course I had to test them so every time I connected on, I'd call it from another office.

    Imagine my surprise as I walked into the office I'd been putting them in to see him pick up a ringing phone (not even one of the ones I'd put in) to hear him shouting down the phone "will you just fuck off?!? I'm busy!!!".

    Apparently he thought it was me calling to test a line again and in his annoyance, didn't notice it was an external ring. Or an existing phone. He says it sounded like a very nice, very confused old lady on the other end of the line, just before he hung up in horror!

    Happy days.

    1. Anonymous Coward
      Anonymous Coward

      Re: Back in the very early 90's...

      Ah colour wires in very early 90s ...

      My first IT transformation project was re-doing all the network at a big warehouse ... The network part went completely OK, we even replaced this old 10base2 BNC cable that was only here for distance reason by a proper fiber ...

      The phone part didn't go so well: the contractor, when re-cabling all phones, had assumed correct wire colours were used and nothing worked.

      Explanation: the bozo from a dodgy company who was normally doing phone wiring would use whatever cable of the day he had all over the place, for many years. Everything was therefore messed up.

      We had to re-cable every office one by one to make it work ...

      Good times, yes :)

      PS: forgot to mention, no-one knew an RS-232 line was going from the entrance of the warehouse up to the HR office for the badges. It was borrowing our LAN cabling panels which we had removed and replaced. Took me days to understand this and restore this darn badging system !

      1. Anonymous Coward
        Anonymous Coward

        Re: Back in the very early 90's...

        I have popsted signs with 'unlabelled wiring will be removed without notice' on all patch panels and demark terminals where I work.

        Below it says 'Unless you want to come back and re-do the job, for free, do it properly the first time'.

        1. The Oncoming Scorn Silver badge
          Go

          Re: Back in the very early 90's...

          I used to loopback data ports to allow Dr Derek to interconnect his equipment in the labs to each other while at Gluxo.

      2. swm Silver badge

        Re: Back in the very early 90's...

        In college we had an AM radio station and the audio and control wires were carried by phone wires to the transmitter site. One day we lost the connection with the transmitter and discovered a telephone man in the basement removing wires to reconnect them according to some obsolete diagram. A little muscle dragged him from the junction box while the wires were reconnected.

      3. Alan W. Rateliff, II
        Pint

        Re: Back in the very early 90's...

        an RS-232 line was ... borrowing our LAN cabling panels

        For every genius solution to a problem there is some poor schmuck who has to deal with it later.

  4. Anonymous Coward
    Anonymous Coward

    Thanks for reminding me...

    ... of the related Spitting Image tune https://m.youtube.com/watch?v=CDlj0jBtYmQ

    1. thosrtanner

      Re: Thanks for reminding me...

      Damn. I was just about to post that too

    2. John Brown (no body) Silver badge

      Re: Thanks for reminding me...

      Wow, you'd almost think it was some sort of standard for easily connecting any compliant devices together or something!

      Instead it was a weird mish-mash of connectors and signal arrangements it actually was, made worse over time as every manufacturer invented new connectors or repurposed other ones for their special device. One fine example being the Cisco router using an RJ-45 for the console interface which was wired differently to the Epson till printers RJ-45 connector. I had many and varied adapters and cables in my toolkit along with spare rolls of cable and connectors so I make yet another custom one as and when required.

      We're almost back to that point now with USB standard, mini, micro, sub-micro and now USB-C and the different functions it can provide needing USB-C to USB A,or USB C to HDMI etc.

      Even SCSI was never this bad! :-)

      1. Fred Flintstone Gold badge

        Re: Thanks for reminding me...

        Even SCSI was never this bad!

        Oh yes it was, and don't get me started on terminators which did indeed terminate, just not as intended.

        I need a drink now. No, just leave the bottle, thanks.

      2. phuzz Silver badge

        Re: Thanks for reminding me...

        "Cisco router using an RJ-45 for the console interface which was wired differently to the Epson till printers RJ-45 connector"

        Which was different again from the one APC used on their UPS's, which they'd usually position so that it was right next to the RJ45 connector for ethernet, and leave you to guess whether plugging the wrong cable in was going to brick your UPS.

  5. GlenP Silver badge

    RS-232...

    I have not-so-fond memories of RS-232 from those days, debugging both hardware and software could be a right pain in the proverbial.

    I ended up making my own test lead set, two cables with 9 and 25 pin D-connectors at one end and a 25 pin at the other, plus a single long extension and a bought in test/breakout box. It served me well for a few years when serial printers and comms were common.

    Hardware/software issues included twice developing suitable hardware and drivers to run a plotter over the same serial line as the terminal. For reasons lost in the mists of time we couldn't use the AUX (or was it PRT?) port on the DEC VT-220 for the first so had to construct a wire tap, for the second we could just set the VT to pass-through but had to tweak the drivers as one of the Calcomp plotter commands would cause the terminal to lock up.

    In a later job we had a MicroVAX 2000 with 4 separate RS-485 connected serial port hubs. The hardware was second-hand (it had been the test/demo kit for the MRP system provider) so the hubs came with a single backplane. It made far more sense to run a single RS-485 connection to the more distant offices instead of large bundles of serial cables but DEC wanted a ridiculous sum for separate PSUs for each hub. I handed it over to our in-house electronics engineer who built me 3 wall boxes to act as RS-485 terminations and power supplies so the hubs could just plug in.

  6. ColinPa

    Danger - building works

    In the days when the heat from the water cooled main frame heated the site and before PCs, we had a new building build next door. One day the machine digging the foundations put it through the main water supply for the site (I heard the effect was like a whale blowing). This meant no main frame, no air conditioning. As this was a "modern building" this also meant there were no opening windows ( or outside awareness panels as they were called). It took a week to fix, and the boyd odour smell was not pleasant.

    In the last 10 years I visited a company who had taken High Availability very seriously, including dual network providers etc. The both came in the front of the building - in through the same hole in the wall. This didn't help when someone did some work in the road and cut though both network cables.

    I also heard of the case when a French company had two network suppliers to cross France. One cable headed north, one cable headed south - what could go wrong? What happened was both cables were rerouted to use the common network infrastructure across France. At the other end, one cable went north, and down to the site, and the other went south, and then up to the site. Im sure youve guessed what happened. Something happened to the common network infrastructure and so both networks were broken.

    1. Anonymous Coward
      Anonymous Coward

      Re: Danger - building works

      "the boyd odour smell was not pleasant"

      I used to work in building called Boyd House that did indeed have its own unique aroma.

    2. Wellyboot Silver badge

      Re: Danger - building works

      HA links ending up in the same infrastructure half a mile away is par for the course but it does allow us to claim 'not our fault' and point at telco who provided the 'HA' at great cost.

      While working for a large french company in the 90s I was amazed to discover that we we in the process of laying direct site to site fibre in new conduits under 1.5Km of suburban Paris streets (senior company execs being good chums with senior local government officials from way back).

      The fibre was only for a remote data centre backup facility and comms backup should a shovel meet the main comms lines at either site, neither of which hosted the head office.

    3. swm Silver badge

      Re: Danger - building works

      "Im sure youve guessed what happened. Something happened to the common network infrastructure and so both networks were broken."

      That actually happened with the original ARPANET with a north and south route connecting the east and west coasts. The phone company routed both channels somewhere along the way creating a back hoe magnet.

      1. jake Silver badge

        Re: Danger - building works

        In late 1977 I managed to take down all the PDP10 kit at Stanford and Berkeley with a software upgrade. Effectively split the West coast ARPANet in half for a couple hours. Not fun having bigwigs from Moffett and NASA Ames screaming because they couldn't talk to JPL and Lockheed without going through MIT ...

      2. Old Used Programmer

        Re: Danger - building works

        That sounds suspiciously like what happened between UC Berkeley and a site they were connected to on the East Coast. In spite of paying a lot to have two, independently routed, circuits, *both* went through the same cable under a farmers field in New Jersey. Said farmer managed to nail the cable and both circuits went down. I believe that (AT&T, probably?) got asked for a serious amount of money for not having provided the independent routing that Berkeley had been paying for.

    4. Alan W. Rateliff, II
      Facepalm

      Re: Danger - building works

      The unknown shared infrastructure can be a nightmare. I had a customer whose Internet uplink is absolutely critical. So we brought both ComCast cable and Embarq ADSL into the office to give us redundant routing since both were subject to sporadic outages, always at the most inopportune time.

      This arrangement worked very well, with ComCast suffering numerous outages and Embarq only a few. Until the tree up the road dropped a rather sizeable branch onto some suspended cables. Both services went out.

      This got sorted during the repair as ComCast had to run a temporary drop from the other side of the property. Not so temporary but to our benefit. Until a few months later when the call came that, again, both connections had gone down.

      Come to find out that during that period, ComCast and Embarq in our area were both routing through Level3, which had suffered a core routing melt-down.

      Nothing can be made fool-proof. The situation is much better now in a new location and new services, but I still expect the shoe to drop.

  7. chivo243 Silver badge
    Pint

    It must have been a Friday

    "I got the carpet guy tucking it under the rug. We are good!"

    And it was crawling up on Pub:30

    Done and dusted!

  8. Richard 12 Silver badge
    Facepalm

    About ten years back

    A colleague was starting up a system and found that the network cable to one of the racks was broken.

    As the rack needed to work the next day for the building "soft opening", they put in a temporary patch cable between the processor in the rack and the patchbay the other side of the room.

    They noted it in the report and formally requested that the network cabling guys fix the in-conduit cable when they were due to come back to site the next week to fix any issues discovered during system startup.

    Two years later, I went to the site and found that patch cable still in place - at about waist height, strung across the middle of the room...

    I assume limbo was popular?

    1. Anonymous Coward
      Anonymous Coward

      Re: About ten years back

      I once worked with a company who was replacing their mishmash of network kit. The company specified to BT/Virgin/NTL/whoever that the WAN line should terminate within 6ft of the Cisco router (so they could use the Cisco supplied 6ft cable)

      After a few cases of "I'm 6ft fingertip-to-fingertip and I can touch both the line jack and the router", "yes, but you're standing in the gangway!" they decided it was easier to supply 5m cables than go through the palaver of booking jobs with BT/Virgin/NTL/whoever to move the network termination to a sensible position

    2. l8gravely

      Re: About ten years back

      It's really amazing how many people are afraid to make any changes at all just in case something breaks and they get blamed. This leads to all sorts of cruft and problems across systems, and is alot of the reason upgrades fail. They are so hesitant because they feel that breaking things might get them shit canned.

      Me, I'm all for breaking things and finding out that those carefully maintained email aliases from 15+ years ago aren't used, couldn't be used, and won't ever be used. But we have to keep them just in case! Sigh...

      1. Giovani Tapini Silver badge
        Trollface

        Re: About ten years back

        You will never know which system they are hard coded into until it's too late...

      2. Anonymous Coward
        Anonymous Coward

        Re: About ten years back

        It's really amazing how many people are afraid to make any changes at all just in case something breaks and they get blamed.

        Also known as hard won experience ...

      3. Terry 6 Silver badge

        Re: About ten years back

        Well, not amazing. Because something will break and they will get blamed.

        It all comes back to the old chestnut we've seen referred to umpteen times here. Crap management creating excessive risk aversion to the point of paralysis.

      4. swm Silver badge

        Re: About ten years back

        I believe that someone at MIT was bringing up a new machine and needed an IP address. They reasoned that a popular machine decommissioned 10 years ago had an IP address they could use. So they brought up the machine and immediately started getting mail that was dormant somewhere in the network for 10 years.

        1. jake Silver badge
          Pint

          Re: About ten years back

          I've heard this story a couple of times over the years. I don't doubt that something similar happened, somewhere (I've heard Berkeley, MIT and UCLA) ... but after ten years? That's suspicious, for many reasons. I'd really like to know more details. I've tried to track it down in the past, but I've come up empty.

          Anybody? If you're talking, I'm buying.

      5. Anonymous Coward
        Anonymous Coward

        Re: About ten years back

        I will admit (whilst bravely posting as anon), that sometimes I've "accidentally" broken something, and then used the "unplanned" downtime to fix a bunch of 'temporary' solutions.

        "Oh no, your mailserver has crashed? Ok, while I was getting it working I also installed those security fixes that you've been refusing to give me a maintenance window to install."

    3. Trygve Henriksen

      Re: About ten years back

      Should have used a much longer cable so that they could make a few more crossings and zigzags across the room. Just one crossing isn't enough to bother anyone.

  9. Anonymous Coward
    Anonymous Coward

    Luxury

    I worked at a UK council where an RS232 would have been heaven.

    Picture an IBM machine spitting out paper tape in to an empty printer paper box, once the box was full the end was feed in to an ICL DME machine paper tape reader.

    So one writing and one reading at the same time, the operators had to test run any programs to ensure the box was big enough as the ICL machine read faster than the IBM machine wrote.

    Now that’s real data transfer.

    1. IanRS

      Re: Luxury

      If the writer could have kept up with the reader you know what would have happened - a tape crossing the room, probably at waist height to cause as much obstruction and risk of being broken as possible.

    2. MarkET

      Re: Luxury

      Pre-made paper tape? Sheer exuberance. When I were lad used to go to mill to mix paper pulp...

      1. MarkET

        Re: Luxury

        Remember Altair DOS & Basic on paper tape. Loaded through ASR-33 teletype after keying in boot loader via front panel switches. Made the Honeywell DPS-6 and Dec PDP boxes look like heaven sent...

        1. jake Silver badge

          Re: Luxury

          "Made the Honeywell DPS-6 and Dec PDP boxes look like heaven sent..."

          I still think that DEC PDP11 kit was the best teaching platform ever.

          1. MarkET

            Re: Luxury

            Tend to agree. All our work was in assembler on the PDP 11/03 and 11/34. The tech guys wrote their own mini operating system hosted on RT-11 to support text processing for newspaper editing and production.

          2. Phil O'Sophical Silver badge

            Re: Luxury

            I still think that DEC PDP11 kit was the best teaching platform ever.

            I really should fire mine up again, after I check the PSU caps. I could do with more storage, but Q-Bus SCSI cards are like hen's teeth, and similarly priced. The existing RD52 still works, but 30MB is a bit tight these days...

            1. MarkET

              Re: Luxury

              30MB! We had RL01...who would ever need more than 5MB per cartridge...

              1. jake Silver badge

                Re: Luxury

                The RK-05 that runs with the afore mentioned Heath still works after all these years ... and I still have a dozen or so working cartridges. At 2.5 megs each, I was pretty certain that I had storage forever. And it only takes up 6U! :-) (That's ten and a half inches, for the rack-impaired.)

        2. Antron Argaiv Silver badge
          Thumb Up

          Re: Luxury

          Luxury was the diode ROM boot loader board.

          1. Will Godfrey Silver badge
            Coat

            Re: Luxury

            Programmable with a pair of wire cutters and a soldering iron.

            We need a maniacal laughter icon!

            1. jake Silver badge
              Pint

              Re: Luxury

              That's side-cutters and wire-wrap, you heathen.

              Have a beer. Steadys the hand, which is useful for this kind of work.

              1. Old Used Programmer

                Re: Luxury

                Also known as "diagonal cutters" or "dikes", for short.

        3. Doctor Syntax Silver badge

          Re: Luxury

          "Made the Honeywell DPS-6 and Dec PDP boxes look like heaven sent."

          I think PDP-8 used the same system.

      2. not.known@this.address Silver badge

        Re: Luxury

        1985, a technical college in darkest Surrey, at the end of the lesson. Lecturer says "...and next week I will tell you about punched tape, which nobody has used for years."

        A week later, he starts the lesson with "As I said last week, this..." (here he holds up a couple of inches of paper tape, yellowed and crumbling at the edges with age) "...is punched tape, but nobody uses... what the hell is that?"

        "That", dear reader, was 18" of punched mylar tape that I'd made the previous week at the site of a well-known (and occasionally lamented) British aerospace company, and was now holding aloft for his inspection... thus diverting him completely from the lesson plan and leading to the one and only time I got any respect from my fellow students :-D.

        1. Anonymous Coward
          Anonymous Coward

          Re: Luxury

          Floppies really didn't like factory environments. Mylar tape for CNC machines was a major advance.

          In the early 80s we were building in-house a simple test machine for a variety of small semiconducting devices. For each one about 8 3-digit test parameters needed to be set. Using the edge-display BCD encoded switches of the day would have meant around 30 of them, allowing for high and low limits.

          This was not really practical. Apart from the sheer quantity of wiring an I/O, machine operators just weren't reliable.

          The answer turned out to be punch cards and a very simple card reader, each card clearly labelled. Turn on machine, wait for first light, feed card, green light comes on, go.

          1. Doctor Syntax Silver badge

            Re: Luxury

            That rang a very distant bell. Way back some retail environments used to have some sort of stock control system whist involved paper tabs the width of tape with a printed label at one end and a few characters' worth of holes punched at the other.

            1. MarthaFarqhar

              Re: Luxury

              https://en.wikipedia.org/wiki/Kimball_tag

              A bored teenager working in a store with the right diameter pin could cause havoc.

            2. Bill from NJ

              Re: Luxury

              I used those retail tags in a clothing store in 1965.

        2. OssianScotland Silver badge

          Re: Luxury

          1989, as a PhD student, I spent some time at the (then) BT Research Labs near Ipswich. On a site tour, I was shown their "small" satellite dish - about 10m diameter, based on the mechanism of a destroyer's gun turret - with a control room straight out of Quatermass (brushed aluminium panels, all the dials, knobs and switches you could want...

          ... And then their "computerised control unit" - a Commodore PET with a punched tape reader!

          I wonder if they still have it?

        3. John Brown (no body) Silver badge

          Re: Luxury

          1985, a technical college in darkest Surrey, at the end of the lesson. Lecturer says "...and next week I will tell you about punched tape, which nobody has used for years."

          The not only did you prove him wrong, put paper tape was still in fairly common use back then. Only a few years earlier I completed my GCE A level Computer studies course. Much of our work was done on a teletype with an acoustic modem link to the local university. Programs written out to punched tape so they could be uploaded and run after hours on the "cheap rate" phone calls by the teacher who remained back late (occasionally with a some of us students). A couple years earlier, we were typing out 5 hole punched tape which was sent to the local town hall to run on their system via an adapter, because they had modern 8 hole readers. 10 years after that, I was doing a job for a factory with CNC machines. Some had RS-232 back to the office for programming. Some used floppies. Most used paper tape.

          1. hoofie

            Re: Luxury

            In about 1990 or so, I was privy to seeing a military-grade RS232 encryption device with its case open. All compartmentalised with gold chips, EMP protection etc.It was used for serial comms across phone lines between some government departments.

            And voila - the encryption key was loaded via paper tape. Apparently the reason was the key could be instantly destroyed.

        4. Shooter

          Re: Luxury

          Five or six years ago I was helping my parents clean out their cellar prior to moving house, and came across a shoebox full of paper tapes from my high school years (mid '70s).

          The tapes that hadn't gone moldy were so dry that they couldn't be unrolled at all without crumbling to bits.

        5. JimboSmith Silver badge

          Re: Luxury

          I did business studies A-level.for my sins and the class was directly after lunch. The teacher had a small class of 16 of us because it wasn't a popular subject. He was going to do product failures that lesson and had two examples for us. We were supposed to study the product and give possible reasons as to why they were no longer on sale. The first was a car with a crap name that I've forgotten which had proved to be a costly mistake. The second was Cherry Coke and he produced some old advertising for the product. We were supposed to discuss this when I put up my hand and said "I'm sorry I don't understand Sir it's still on sale!"

          "Maybe in America it is but not in this country."

          "Sorry again Sir but it is available in the UK."

          "Alright it might be available in specialist shops that sell imported foods but you can't just buy it everywhere."

          "Erm I had some for lunch Sir"

          "No you didn't and would you please stop disrupting the class."

          He was horrified when I retrieved an empty can of Cherry Coke from the bin. He asked where I'd bought it and I said Tesco in a pack of six. I said I could bring a full one in for him tomorrow or if he'd give me permission to leave school now..... I could get him one much faster as the corner shop near the school sold them too. I was not popular with him for the rest of the week.

      3. The Oncoming Scorn Silver badge
        Pint

        Re: Luxury

        Have a upvote for the passing of Tim Brooke-Taylor, who had a hand (& presumably a pen) in writing "The Four Yorkshiremen" sketch.

    3. Dave559 Bronze badge

      Re: Luxury

      That paper tape setup sounds like the original predecessor to places where the "workflow" is to print out documents, so that they can be scanned in later (but not as an OCR scan, of course, and always at an angle of at least 5° from true), so that they can be sent as an attachment to an email message...

      (Extra bonus points if the original document didn't really contain any formatting that couldn't have been adequately conveyed by a suitably laid out monospace plain text email anyway.)

  10. Gene Cash Silver badge

    Remember serial breakout boxes?

    They were about the size of a phone and an inch thick. You'd open it like a book and it'd have an RS-232 connector on each side, one female and one male. It had pins that broke out the connections that you could jumper as appropriate.

    Great for quickly finding out if you needed to swap pins 2-3, for example. You'd then make a cable that duplicated the jumper arrangement.

    Man, I also miss mid-80s Radio Shack. That place was heaven back then.

    1. GlenP Silver badge

      Re: Remember serial breakout boxes?

      Yep, see above!

      I'm wondering where mine is as I'm sure I wouldn't have disposed of it (I never throw out IT kit!)

      1. Andrew Moore

        Re: Remember serial breakout boxes?

        I know where mine went- if was "borrowed" by slaesdroid who took it to a client site and left it there. After a year of me consitently badgering the 'droid for the return of the box, I was taken to one side by the boss and told to drop the issue. I responded by buying a deluxe breakout box and billing it to the company.

    2. jake Silver badge

      Re: Remember serial breakout boxes?

      "it'd have an RS-232 connector"

      Or any other data cable connector (RS422, GPIB, etc.). The good ones come with red and green LED pairs on each pin. I still have a pile of 'em. They come in handy occasionally.

    3. IanRS

      Re: Remember serial breakout boxes?

      I am sure mine must still be around somewhere, although it was a little smaller. An open case with a 25 way connector on each end and 25 pins sticking up. Jumper leads could be added as necessary. The last resort in my serial toolkit, which also included a long straight-through cable (1-1, 2-2, ... 25-25), short adapters for common requirements such as null-modem or 25-9 serial, gender-benders. If two boxes could talk via a common protocol through a 9 or 25 pin D socket, I could probably connect them.

      1. Anonymous Coward
        Anonymous Coward

        Re: Remember serial breakout boxes?

        Interfakers...?

        I can remember my first boss using one to troubleshoot serial - but then it was replaced by Dec MMJ cables which were rollovers - so just missed those pleasures...!

    4. Phil O'Sophical Silver badge

      Re: Remember serial breakout boxes?

      I still have a couple in a desk drawer. And the bit of veroboard with a 25-pin D-type on each end and a selection of LEDs and resistors to show line state. It must be getting on for 40 years old now, best debugging tool I ever made.

      Then again I've only recently scrapped an HP 4951C protocol analyzer, complete with pods for RS 232/423 and serial synchronous comms. Nice kit, but none of our recent serial lines ran at less than 2Mbit/s, and it topped out at 64kbit/s.

    5. KarMann Bronze badge
      Paris Hilton

      Re: Remember serial breakout boxes?

      'They were about the size of a phone and an inch thick.'

      The size of a then-phone or a now-phone?

    6. Havoc

      Re: Remember serial breakout boxes?

      Not only do I remember them I even used one a month ago or so. Together with a couple of DB-25 to DB-9 adapters.

      1. Old Used Programmer

        Re: Remember serial breakout boxes?

        Grrrr... There is no such thing as a "DB-9". There is a DE-9 connector.

        1. jake Silver badge

          Re: Remember serial breakout boxes?

          "There is no such thing as a "DB-9""

          I beg to differ. I've driven a couple of them. Almost took a 2009 Volante as partial trade on a horse, until sanity prevailed. Or was that SWMBO?

          I've also seen a D-sub, B-sized connector with only 9 pins, in a single line down the center ... They were in some old test equipment that we were re-purposing. I have absolutely no idea why they built it with such a non-standard part ... In about 1990 I called Amphenol for spares, they told me that they made them for a limited time in the early 1970s for a government contract, and they sent me a box full of old stock, gratis (individually wrapped, complete with pins, hoods & hardware). I probably still have a dozen of each (male and female) in my junk collection. I've never seen 'em anywhere else.

    7. Antron Argaiv Silver badge

      Re: Remember serial breakout boxes?

      Still have mine.

      I used to joke with my cow-orkers that the one thing I would always be doing, no matter where I worked or what my title was, would be making RS-232 cables.

      True up until about 10 years ago, when USB actually became usable.

      I've traded in my sub-D pin crimp tool for a modular connector crimp tool.

    8. richardcox13

      Re: Remember serial breakout boxes?

      Yes they were useful, but for real troubleshooting and testing a protocol analyser was even better.

      A breakout box with an attached computer that would allow you to record and show you the data being sent. Along with changes to hardware signals. For when you wanted to push things programmable to emulate another device.

      Like this.

    9. DemeterLast

      Re: Remember serial breakout boxes?

      80s Radio Shack also sold serial and parallel switch boxes. In the Dear Old DOS Days of AutoCAD, I had 7 or so computers connected through a byzantine array of serial and parallel switch boxes to allow the CAD operators to print to the dot matrix printer or the pen plotters. There is still 50 meters of DB-9 and DB-25 cable above the ceiling to this day.

      Woe betide the operator who failed to check with the others before manipulating the switches to access an output device.

      1. Nunyabiznes Silver badge
        Pint

        Re: Remember serial breakout boxes?

        And I thought I was the only one that had to keep a pile like that running.

        Beer -->

    10. AmenFromMars

      Re: Remember serial breakout boxes?

      Yep, still got mine in the garage and my protocol analyser in a cupboard at work and a bit error rate tester with a built in breakout box. We've still got loads of RS232 and serial lines for out of band management over ISDN2, can be a real lifesaver when something goes down and you're 100s of miles away.

  11. jake Silver badge

    I remember things differently ...

    "There was no email or messaging back then"

    Yes, there was. Maybe not in program loaders disguised as operating systems, but that doesn't mean they didn't exist. And even with those toy computers, the BBS world was tiny, but there. If you had a modem, of course.

    "nor was there the remote access"

    Yes, there was. TehIntraWebTubes was well over a decade old by then.

    "hasty sending of a patch"

    Yes, there was. (Sometimes the "hasty" was via motorcycle ... good bandwidth, but bad latency.)

    "A small business computer was size of a washer and dryer and cost around $100,000."

    My Heath H11 had a 16 bit PDP11 CPU, was about the size of three modern large desk-side computers and cost me just under $3,500 (I had a lot of accessories and maxed it out on RAM ... the base kit was about $1300). It was my xmas gift to myself in 1977.

    1. A.P. Veening Silver badge

      Re: I remember things differently ...

      Yes, there was. (Sometimes the "hasty" was via motorcycle ... good bandwidth, but bad latency.)

      Don't forget the occasional packet loss due to a crash.

      1. Anonymous Coward
        Boffin

        Re: I remember things differently ...

        In communications theory we don't call it a crash. We call it a collision.

        1. A.P. Veening Silver badge

          Re: I remember things differently ...

          That is when two (or more) packets collide, if the carrier goes down without a collision it is a crash.

          1. Anonymous Coward
            Anonymous Coward

            Re: I remember things differently ...

            I thought people would realise that the blue head icon meant it was a joke, not an attempt at a pedantic correction. Some newspaper style books prefer "collision" for vehicle impacts over "crash", which is considered too vague.

            1. A.P. Veening Silver badge

              Re: I remember things differently ...

              Highly technical: a vehicle leaving the road after loss of control (unexpected flat tire) and going into the water could be called a collision with water, but most people would at the very least be a bit surprised by that choice of words.

              1. Anonymous Coward
                Anonymous Coward

                Re: I remember things differently ...

                Is this comment based on experience? And what were you doing riding the bike on a towpath?

                Our youngest grandchild managed to do this, and duly fell in the canal after hitting a mooring rope. He didn't call it a crash or a collision. He called it "my bike threw me in the water."

              2. Trixr

                Re: I remember things differently ...

                A plane crash over land is classified as "collision with terrain".

      2. David 132 Silver badge
        Coat

        Re: I remember things differently ...

        When it worked, it was a Triumph.

        Just the same as nowadays, much slower if Norton was involved.

        1. jake Silver badge

          Re: I remember things differently ...

          "When it worked, it was a Triumph."

          Someone must have rewired it from scratch, then.

          (I have owned a couple Triumphs from that era, I know of what I speak.)

          1. Anonymous Coward
            Anonymous Coward

            Re: I remember things differently ...

            I owned three of them, then I decided to give up masochism for Lent and never looked back, because looking back at Kawasaki triple speeds is a recipe for disaster.

            However, Triumph electric problems I could always fix, even if it meant a home made diode bridge, replacement headlamp and non-Lucas coils. But the number of people I knew with seized Nortons was considerable,and that couldn't be fixed with basic electrical tools. And then there were the early Commandos with the rubber mounts which became loose and made the handling very, very interesting in an emergency -or as the person I knew who had one put it "I beat Jesus, I died twice on the operating table."

          2. OzBob

            Re: I remember things differently ...

            you do know why the Brits don't make computers anymore? because they couldn't figure out how to make them leak oil.

            1. jake Silver badge

              Re: I remember things differently ...

              That and the Lucas electrical ...

              1. Anonymous Coward
                Anonymous Coward

                Re: I remember things differently ...

                Lucasifer, Prince of Darkness.

                Lucas, in fact, had a pact with the Devil. The Devil would allow their ignition systems to work most of the time, in exchange for which he got the souls of all the people who swore at Lucas equipment. You can figure out the rest with game theory. Not unreliable enough for the British manufacturers to go elsewhere, unreliable enough to keep a good supply of furnace stokers.

  12. Boris the Cockroach Silver badge
    Unhappy

    Oh god

    RS232... the memories... the noise... you wouldn't understand.. you weren't there.

    Take a fresh faced slightly(at this stage) cynical cockroach, add in a PC, and a bunch of Fanuc robots, both have RS232 interfaces so it should be easy to to link them together (breaks down sobbing again)

    Yupp wire 2 to pin 3 etc etc etc and we have the first cable made up, plug it in and nothing, change the PC port setup, nothing, change it agaain , nothing ..hmm.

    yupp 9600 baud... I know... no flow control.... WTF is an 087 alarm? ahh buffer overrun, TEN BYTE BUFFER YOU ARE KIDDING ME!!!, ok says here uses software flow control when buffer is full, set the PC to software mode.... yay got 12 bytes in the machine before it stopped... hmm and hardware flow control to resume sending!!!!! what the *&%%*&%*&%(^*(&ing idiot designed this?

    (starts drinking)

    OK.... checks sources on the internet , all of them go LOL when asked about using windows to setup the rs232 port to talk to Fanuc machines

    Several days later after writing a small java program to directly control the serial port .... and we have success.... wait for the xoff.... then wait for CTS line to change before sending more data (remembers his cheering and happy dance, then collapses sobbing again)

    Then the boss comes up and says "You taken 4 days to make ONE zarking wire.... what the zark have you been doing all this time?"

    (closes the door and resumes his isolation with his plastic dinosaurs)

    1. Version 1.0 Silver badge

      Re: Oh god

      Back in the old days writing code to read serial data from an RS232 line was hell on earth - everything would work most of the time but never all of the time until I "discovered" Interrupts! Once I read the serial controller with an ISR everything worked at all baud rates. Ever since then I've written ISR code for all time-critical functions.

      1. Anonymous Coward
        Anonymous Coward

        Re: Oh god

        In the "old days it may have been bad, but ever try talking to RS-232 devices using VB.net?

        At first, everything looks great, lots of pretty functions to wrap everything up. Then you actually try to use the stuff... ugh!

        For years I assumed the troubles were due to my lack of coding ability. Eventually I found some real-world discussions of the shortcomings of VB's serial code. (Not that said discovery invalidated the premise of me being a lousy programmerl.

      2. dajames Silver badge

        Re: Oh god

        Back in the old days writing code to read serial data from an RS232 line was hell on earth - everything would work most of the time but never all of the time until I "discovered" Interrupts!

        Interrupts? Luxury!

        I was contracting at one of the parts of the Racal empire in the late 1980s. Our standard workhorse was an Olivetti M24SP running DOS, with no networking.

        One of our suppliers tried to interest the company in the newfangled "PS/2" range from IBM, and someone managed to wangle the loan -- just for a day, because they were in short supply -- of a Model 30 (the crap one with the 8-bit CPU and, more importantly for us, an ISA expansion bus rather than MCA). We had developed an ISA bus encryption card, and wanted to see whether it would work in the PS/2.

        What could be easier? Just copy the software onto a diskette and ... Oh, No! Our Olivettis all had 5.25" floppy drives, but the PS/2 had a 3.5" drive.

        So, we found a laplink cable to connect the machines together. I wrote a little file sending routine in C to run on the olivetti, and a file receiving routine in assembler, in debug (it was all we had) on the PS/2, using the awful ROM BIOS serial port routines because that was the easiest thing to do. I implemented a very, very, simple handshake (I think I just echoed every character received) and ran a simple test. I don't think it worked first time, but before long it worked well enough to transfer the laplink software (and we all went for coffee while that transferred) and then we were in business.

        Our hardware did work in the Model 30, and we were able to return the machine at the end of the day having run all the tests we needed. Before we gave it back, though, we got the supplier to give us a 3.5" floppy and we kept a copy of laplink, for the next time.

        My little program, written in debug, is one "temporary fix" that was NOT kept beyond the first use.

  13. Anonymous Coward
    Anonymous Coward

    RS232 is alive and well

    In the calibration business, there's a lot of RS232 connections still in use. Typically they're for adjusting an instrument or changing its settings, if it doesn't have a display and buttons. Easy to use, too - plug USB-to-RS232 adapter into computer, fire up HyperTerminal or PuTTY, initiate link to device, and refer to the manual for the commands.

    The big difference seems to be that the RS232 cable doesn't stay plugged in all the time.

  14. Peter Gathercole Silver badge

    Long RS232 cabes

    I have two stories about long-run RS232 cables.

    The first was when I worked at a UK educational establishment. Pretty much everything was jury-rigged there, because they did not want to pay professionals to do things like laying cables. Anyway, my PDP11 was having some cables run down the hall to the lecturers offices, where their newly bought BBC Micro's were to act as terminals (and, in fact, were also connected to the floor Econet). The cables were laid, and loosely tied to a convenient support. Everything worked fine. One of the other technicians then decided ti tidy it up, and proceeded to tack it to whatever was available using staple gun instead of wire clips....

    You can guess. Staple straight through the cable, shorting pins 2 and 3 (as we later found out). No immediate problems, because the BBC micro was not being used. But the PDP11 started getting slower and slower, and after about 4 minutes or so, crashed with a I/O buffer overrun error. Rebooted, and the system was fine for four minutes, and then crashed again.

    Finally realized that on the port with the damaged cable, the system was sending out the login banner, which was promptly read back in as input from the terminal (pins 2 and 3 shorted). This generated multiple new login banners, exponentially increasing the amount of traffic until the PDP11 (which was very good at handling character I/O normally), just gave up the ghost,

    Once found, rather than laying a new 25 metre cable, the rather embarrassed technician cut the damaged bit of the cable out and spliced in (using screw terminal blocks, I believe) a couple of inches of new cable,

    The second story is from a factory floor, where a terminal was in the middle with the cable, the maximum length permitted by the RS232 standard, was run through the roof. Periodically, a couple of times a day, the computer it was attached to reported TTY Hog messages, and promptly shut the terminal down. I was giving remote support to a VAR, and after several days getting them running diagnostics on the port and checking the cable for damage or shorts, I asked where the cable was routed. They said that they had run it down the existing cable runs with everything else. After a few seconds thinking, I asked what else was fun down the runs. "Oh", they said. "Pretty much everything". Apparently, this included power for the electric motors that ran large industrial hoists for moving things around the factory floor. "OK", I said, "Is there any chance that the ports shutting down happened at the same time that these hoists were operating,,,,".

    Turns out the motors were very dirty, and drew a lot of current. The rapid current spikes generated by the motors was being picked up as interference on the RS232 cable, which was not good quality shielded cable. It would have worked fine in an office environment, but in an industrial environment, it was not up to the task. The system tried it's best to make sense of the noise but failed, shutting down the port. Anyway, they actually relocated the terminal to a different part of the factory floor with a much shorter cable run and good quality cable, and I never heard from them again.

    1. A.P. Veening Silver badge

      Re: Long RS232 cabes

      You should have split those stories in different posts, each deserves its own upvote.

    2. Anonymous Coward
      Anonymous Coward

      Re: Long RS232 cabes

      The maximum length permitted by the RS-232 standard assumes you are not using double screened very low capacitance cable, since 2500pF is also allowed. Not cheap, but overcame a length problem connecting a Unix box to an HP computer without needing a repeater.

      We also, with great cunning, managed to run it outside the building about two floors up away from the electricians and their desire for lots of overtime.

      When I think of the efforts we needed then to try to get 16800 Baud over a 50m link, I'm kind of impressed with progress.

      1. the spectacularly refined chap

        Re: Long RS232 cabes

        There isn't a maximum length in RS232 and never has been. The only mention of a specific length is in the preamble discussing the aims of the standard rather than any inherent technical limit. Lines measuring hundreds of feet are quite common and have been for decades.

        Note I still use the present tense too, it may not been in use as much these days, mostly for console and configuration ports, but still widely used. I still keep a couple of serial cable working sheets in my ring binder portfolio thingy - the sheet is designed to avoid silly transcription errors which in my experience are the biggest hassle with RS232. One side dedicated to RJ45 modular adapters, the other for more general cables. Certainly used one within the last month, I can remember what it was for.

        1. Anonymous Coward
          Anonymous Coward

          Re: Long RS232 cabes

          Line drivers with rs422 can do up to 1200 meters. We had some of them for low speed (4800/9600 baud) communications.

      2. jake Silver badge

        Re: Long RS232 cabes

        "the efforts we needed then to try to get 16800 Baud over a 50m link"

        Gandalf had what they called "line-drivers" that could do that out of the box. The one I'm holding in my hand as I type can do 19,200. It's about the size of a flip-phone.

  15. Andrew Moore

    Many years ago I needed to get an RS232 connection from the basement to the 1st floor of the office I was working in. At the time there was a mass of twisted pair cables that ran around the building, used to hook all the phones up. I was able to isolate a couple of unused pairs and hooked up the RX, TX and GND. The hack worked a charm and the data flowed.

    Fast forward 3 months. The workers came into the office one Monday morning to find that the phone system was not working. Going on the fact that I was the last person "messing" with the system, the boss decided that my hack was responsible for the failure (bear in mind it had been working fine for 3 months). So I set about unwiring my makeshift RS232 cable. And surprise, surprise, it failed to make any difference. The non-working phone system remained non-working. So finally the boss had to bite the bullet and call in a proper phone engineer to sort the problem out. It took another day but the phones started working again. And nothing more was said.

    But here's the thing, I knew the phone engineer outside of the office and we ended up bumping into each other later that year and decided to go for a pint. I asked him about the phone job and he laughed- Apparently, the boss had decided to change the carpet in his office. So he decided to do it on the cheap and he and his father-in-law had come in on the Saturday, pulled out the old carpet and replaced it. The fault with the phones? They'd used a stapler to fix the carpet and managed to put a staple through the phone lines. Not once, but many times.

    1. Antron Argaiv Silver badge
      Thumb Up

      I can top that.

      Down from the mainframe, into the basement, along the corridor into the basement of the adjacent tower and up 10 floors.

      A good 500 meters. Well beyond what RS-232 should have been able to do.

      Worked a treat! Don't remember the baud rate, but it might have been 9600.

      We did use phone wire and "66 blocks" to terminate the data lines as well as the phone lines (in separate closets, obviously). I still have some discarded ones in my home basement, where they connect outlets in each room to a wired Ethernet switch. 100Mbit/s over "CAT3" cable seems to work fine.

  16. RobThBay

    Ahh... yes... the good old days of RS232 and wrestling with handshake/flow control lines trying to get equipment from different manufacturers to work together.

    After reading this story I went down to the basement and started poking through some boxes that haven't been touched in ages. Guess what I found besides some DB25 and DB9 connections? My old 25 pin breakout box!

  17. The other JJ

    Talking of electric motors...

    Back in the mid to late '80s we supplied a system to an office plant rental company, the sort that supplied and maintained potted plants to offices all over London. A 386 box running Xenix with about six serial terminals, it was installed late Autumn when they said business was quietening down and had run fine through the winter until suddenly the customer complained that it was crashing a couple of times a day most days. Suspecting something to do with the usage increasing we took a look and did the usual sort of diagnostics but couldn't find a problem, and after a couple of weeks the problem went away. Some months later the problem started again so I went in to have another look. I wanted to speak to our contact who'd just gone out to their massive greenhouse and as I joined him I heard a grinding sound and looked up to see the windows being opened by a system of rusty gears and motors. "Yeah, it's controlled by thermostats" he said, pre-empting my question. "...and it happens in spring and autumn but stays closed all winter and open all summer?" I hauled him back to the office and sure enough we were met by the users waiting for the system to reboot. One UPS later (that they'd said they wouldn't need when we originally quoted) and they were happy horticulturalists.

  18. Will Godfrey Silver badge
    Happy

    An oldie, but a goodie

    A communications problem

    Customer: {mumble} {mumble} {complain} getting worse {mumble} You fixed the last one so why can't you do this one?

    Us: We would if we could get the parts. Most of the chips on the board have been obsolete for years. We just can't get them anymore.

    C: {woe} {woe} But the machines have years of life left in them.

    U: Well, as we suggested before, we could always fit modern controllers to them as they fail. This could actually work out cheaper than trying to fix the old ones.

    C: No, you'd have to do all of them at once and I can't afford that.

    U: Why would we have to do them all together?

    C: Because they all have to talk to each other.

    U: Well, modern controllers can be configured to talk to the old system.

    C: No they can't. There's this special system installed by Radiospares.

    U: Pardon?

    C: The machines can only talk to each other with this. There's some board or something fitted in all of them.

    U: {collectively scratches head and asks around} Can you be more specific? None of us know of any system that Radiospares have designed, and we have never heard of them doing installations.

    C: {smugly} Well it *is* an old system so I expect you young engineers haven't have come across it.

    U: Does it have a name or anything?

    C: Yes of course, and a model number. It's the RS-232

    1. herman Silver badge

      Re: An oldie, but a goodie

      Ayup, few people know where RS Components came from, but they didn't invent RS232. AFAIK that RS stands for Recommended Standard, unless it is maybe a backronym.

      I had a similar but more modern conversation with a salesdroid: Do you have Lucky-Goldstar something or other... No, we have... There it is, Lucky-Goldstar... That is LG! Well, many years ago, Lucky bought Goldstar and became Lucky-Goldstar, LG... He then did a Google search to confirm what I said.

      1. chuBb. Bronze badge

        Re: An oldie, but a goodie

        Try asking in pc world for Hewlett Packard spares, if sales droid looks like they might remember polyphonic ringtones being a thing on there way to preschool the confusion and quick passing on to a senior is funny.

        Really miss d connectors on pc's as it killed my sport of trolling sales staff while other half was clothes shopping. Does this "apricot pc feature a bi directional parallel port?"

        Scuttle off out back to ask the guru

        "yes"

        Is its serial ports uart compatible...

        Rinse and repeat until they loose will to live

        1. Andy A
          Happy

          Re: An oldie, but a goodie

          The predecessor to the Apricot in ACT's range - the Sirius 1 - actually DID have a bidirectional parallel port.

          There was software (and matching hardware) which made it perform with IEEE-488 kit.

          And no, you couldn't treat the serial port as though it was a minimalist IBM PC UART. It handled proper mainframe-style synchronous comms, with clock signals on 15 and 17.

  19. herman Silver badge
    Black Helicopters

    Military equipment still use lots of RS232, RS422, RS485 and RS423 interfaces. Few know what RS423 is...

    1. Will Godfrey Silver badge

      I seem to remember the BBC Model B used RS423 - which rather surprised everyone, but to all practical purposes it seemed to behave exactly the same as 232.

      1. John Brown (no body) Silver badge

        And the bloody silly DIN plug they chose that was keyed to fit in either of two ways. Always remember the mark the plug so you know which is up!

    2. chuBb. Bronze badge

      As do most traffic lights and motorway signage, God help us when smart motorways are connected by USB and "layer 7" application "firewalls" (marketing bs they block behaviours not connections, more of a playpen than a firewall in my mind)

  20. Johnny Canuck

    How about

    Converting 8 bit ASCII to 5 bit Baudot so you can use a 1930s mechanical teletype as a Linux terminal. A thing of beauty.

    https://www.youtube.com/watch?v=2XLZ4Z8LpEE

    1. herman Silver badge

      Re: How about

      There are still a few military systems and terminals for the deaf/blind that use Baudot. Special forces still use Morse also. Some things never die, you just wish they would.

  21. DaemonProcess

    Sinclair ZX Spectrum comms

    Before the days of Spectrum emulators, I managed to copy some bits of Sinclair ZX Spectrum BASIC programs which had sentimental value to an IBM PC using 6 paper clips and a piece of twin+earth. It did require an RS-232 expansion box on the speccy but still worked, albeit at 50 baud only. Faster speeds up to 9600 were only possible for brief periods because s/w flow control didn't seem to work very well and I had run out of paper clips, so h/w flow control wasn't possible. Actually the Sinclair BASIC wasn't much different to QBASIC and the programs ran fine. I treated the PC as a line printer, transferring the code using LPRINT command.

  22. Barrie Shepherd

    Memories

    In my working days (before Ethernet was the norm) I dealt with many systems using distributed data connections using RS232/422. There was always a need for a modem eliminator or reversed cable and it is ingrained in my memory that a modem eliminator is 4 to 5, 6 to 8 to 20, with data on 2 & 3, 7 data ground.

    A couple of years ago I was asked to assist with a problem between two pieces of equipment connected by RS 422 over 1 metre of cable. The suppliers at each end were blaming each other. Their local staff did not understand RS connections. A simple observational exercise showed that ones mans DSR, CTS, DCD was not the same as the other. I made up back to back D25 connectors in a double ended shell, transposing the appropriate wires, with a switch in the DCD line marked 'Energise', and stuck a label to the unit it saying "Interface Dongle".

    I showed my 'significant' knowledge by using the switch to fail the link. I should have potted it and charged them £500 apiece.

  23. rcxb Silver badge

    Come with us to the 1980s, when computers cost proper money

    The ZX81 kit debuted in early 1981 at £50 (about £200 in 2020).

    1. Tom 7 Silver badge

      Not a valid comparison. A pint was about 30p in my local then so that's over £600 now, Remember inflation doesnt take into account things people really buy.

  24. Camilla Smythe

    Hmm. 1982 Channel Four. Now our first programme. Countdown.

    Produced and Broadcast from Yorkshire Television in Leeds. My first student placement was in part spent grovelling around under the floor in the MCR, Master Control Room, tracing and ring colour-coding 75Ohm video cables... the old sticky labels had fallen off and the documentation needed, cough, updating. The supervising engineer had recently self eliminated himself via a political power struggle and was working notice sorting this stuff out. We finished things up in time and the evening of the day before broadcast he called me to the end of one of the racks to proudly show me a boot sized DC powered electro-mechanical RF relay bolted to the rack. "This is where our Channel 4 feed leaves the building." he said with a big grin on his face. The next evening the relay went *clunk* and Richard Twice Nightly and Carol Vorderman burst onto the airwaves in Countdown. https://www.youtube.com/watch?v=03c9vit5G4w 4:03

    1. J.G.Harston Silver badge

      Re: Hmm. 1982 Channel Four. Now our first programme. Countdown.

      Originally Calendar Countdown. :)

  25. Grinning Bandicoot
    Megaphone

    Temporary = Finagle's constant

    Two theories on temporary: 1) works off the idea that its working don't mess with it until we get caught up with all the work and will see some slack time. 2) the other idea is a result of accounting. Permanent items are capitalized and have records for depreciation and maintenance. The temporary items are a costed out and minimal records are kept meaning that a when you fix up for a project, alter it and improve it and long after the capital item is gone, the temporary item is near new and highly valued by those who use it. Summing up one theory is based on an improbability (read as impossibility) and the other based the fairy tale of book value. I am NOT going to remark upon the use of temporary around the word taxes I do believe that the moderator would not permit obscenities.

  26. ItWasn'tMe
    Trollface

    Interface poker

    I'll see your RS-232 and raise with a V.35

  27. sisk

    Smart person: "This is a temporary fix. It needs to be done properly soon."

    Dumb person: "Nah, it's working now so we're good."

    Smart person: "It'll work for a week or two at most."

    Dumb person: "That's OK, you can just come fix it again, right?"

    Yep. Sounds about normal.

  28. Old Used Programmer

    Need to check....

    I think I've still got a box full of RS-232 cables ranging up to at least 50' long.

  29. silks

    Portakabins in Schools were "temporary" also.

    See above for further details...

    1. Glenturret Single Malt

      Re: Portakabins in Schools were "temporary" also.

      Also post WWII prefabs as "temporary" housing in areas that had suffered badly in the blitz. In my home town, they were still there when I was going to school in the 50s.

      1. J.G.Harston Silver badge

        Re: Portakabins in Schools were "temporary" also.

        In my home town they are still there *now*. Every now and then an occupant dies, and the councilhousing association strips and rebuilds it in brickwork.

  30. TimGJ

    This reminds me of something in ancient history when I was the resident VMS guru somewhereback in the mid 1990s. We suddenly urgently needed some code which used VMS' password system, so I hacked something together in a great rush in C in an hour, with all manner of comments along the lines of "Not production grade code. Do not use this!"

    Needless to say it was the one bit of code I wrote for the company which was then reused on every system they shipped thereafter.

  31. Arbuthnot the Magnificent

    Lash-up

    A firm I worked for many moons ago "splashed out" and upgraded the office network cabling to CAT-5E, but refused to put any spare cabling in to allow for growth - to keep costs low they only put in exactly what was needed at the time. Fast forward a few months and a bunch of new starters are announced - all needing PCs and phones. I could install small switches by the clusters of desks to handle the extra data connections but the phones were analogue, so I'm ashamed to say I ended up splitting CAT5 cables to connect more than one phone through, with a similar mess at the patch panel. This was in place for at least a decade before they went VOIP.

  32. Andy1

    Remember the Sinclair Spectrum interface II, this had an RS232 interface. The manual labelled all the connections BUT they weren't labelled as to what they were they were labelled as to what they should be connected to at the other end, much head scratching required to get a connection working.

  33. Paul Cooper

    I worked with a lot of prototype electronics in the 1980s; data logging for ice-penetrating radar. In those days, there were only two "standard" ways to connect equipment - RS232 or Centronics. And the vast majority worked with RS232. As others have said, "standard" isn't really a good description; there were so many variants that a breakout box was an essential tool when working with them. It wasn't just the physical connection - software things like baud rate, 7 or 8 data bits, 0 or 1 parity bit, software or hardware handshaking - the list was unending, and was often controlled by the setting of obscure DIL switches or jumpers.

    That said, I was working with a bare Z80 single card computer, and once you'd got the hardware sorted out, the software (written in Z80 assembler) could be remarkable simple using an interrupt based system. I think that my code for reading an RS232 line was less than 10 instructions - I forget exactly at this distance of time, but less than ten, and perhaps only 5 or 6. For various reasons, my entire software suite was entirely interrupt-driven - the main program was simply a loop that dumped data from a buffer to an output device, with incoming data using interrupts to load data into the buffer. On one recording device, the only problem was that it was a 4 track device, and when a track was full, there was a lengthy rewind (something like 15-20 seconds), and the length of buffer required would only JUST fit in the available memory - 2 or 4 kbytes of RAM!

    1. J.G.Harston Silver badge

      Probably something like:

      ISR:

      IN A,(serStatus)

      BIT RxRDY,A

      RET Z

      IN A,(SerData)

      LD HL,(bufin)

      LD (HL),A

      INC HL

      LD (bufin),HL ; NB! FIXME: no over-run check

      RET

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