[HN Gopher] IBM, sonic delay lines, and the history of the 80x24...
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       IBM, sonic delay lines, and the history of the 80x24 display (2019)
        
       Author : rbanffy
       Score  : 77 points
       Date   : 2026-03-15 11:06 UTC (11 hours ago)
        
 (HTM) web link (www.righto.com)
 (TXT) w3m dump (www.righto.com)
        
       | lysace wrote:
       | No idea if this was a factor, but 80x25 on the IBM PC allows for
       | showing 80x24 plus that extra line of function key labels:
       | 
       | https://en.wikipedia.org/wiki/IBM_BASIC#/media/File%3AIBM_Ca...
       | (IBM BASIC screenshot)
        
         | bluedino wrote:
         | Imagine when edit.com came out and QBASIC used it for the
         | editor. You lost two more lines of valuable code space!
         | 
         | https://en.wikipedia.org/wiki/MS-DOS_Editor#/media/File%3AMS...
        
           | jtarrio wrote:
           | You know, this is funny because QBasic did not use EDIT.COM.
           | Instead, QBasic was the editor and EDIT.COM was a simple
           | program that called "QBASIC /EDIT" :-)
        
             | bluedino wrote:
             | It was basically the same thing. That's my point.
        
           | lysace wrote:
           | I recently went back to my 1993 Turbo Pascal code (mostly 2D
           | VGA and Sound Blaster game engine experiments) on period
           | correct hardware.
           | 
           | I was surprised by how claustrophobic it felt to only see 21
           | lines of code in e.g. Turbo Pascal 7.0. Still didn't like the
           | squashed 80x43 mode.
           | 
           | https://winworldpc.com/screenshot/c38a28c3-84c3-ba28-1011-c3.
           | ..
           | 
           | Then I remembered how larger displays and xterm felt like
           | such a liberation a few years later.
        
             | rasz wrote:
             | Power users had superEGA with 132 column 40/43/44/60/66 row
             | modes.
        
               | lysace wrote:
               | I think mostly just Lotus 1-2-3 (the standard textmode
               | spreadsheet application of the time) supported that?
        
       | hanfoo wrote:
       | Deeply fascinated by these historical threads. It is precisely
       | the various design choices made throughout history that have
       | shaped the computer systems we use today.
        
       | II2II wrote:
       | Tangentially related: is there a history covering IBM's
       | development of microcomputers? It is clear that the traditional
       | story of the development of the IBM PC leaves out many important
       | details. There the 5100/5110/5120, which goes back to the
       | mid-1970's and reflects the stereotype of IBM. There is also the
       | System/23 DataMaster, where the hardware seems to be the basis of
       | the IBM PC. This seems to go against the traditional story that
       | the IBM PC was some sort of renegade project. (If anything, they
       | appear to be companion projects. The main difference being the
       | DataMaster's focus upon IBM firmware/software.)
        
         | kens wrote:
         | Like I need another big project :-)
         | 
         | The IBM Datamaster is an interesting system, but it was doomed.
         | It had an 8-bit Intel 8085 processor, cost $9000, and came out
         | in July 1981. The IBM PC had a 16-bit 8088 processor, cost
         | $1565, and came out a month later. So there was no reason to
         | buy a Datamaster
         | 
         | There's a good description of Datamaster in "A Personal History
         | of the IBM PC" by Dave Bradley (one of the PC's designers).
         | Unfortunately, it's paywalled.[1]
         | 
         | [1] https://doi.ieeecomputersociety.org/10.1109/MC.2011.163
        
           | II2II wrote:
           | That sounds like a great starting point. There's a university
           | library 500 meters from where I work, so bypassing the
           | paywall ought to be easy.
           | 
           | And thank you for all of your articles over the years. They
           | border so close to applied physics they are fascinating
           | reads.
        
       | veltas wrote:
       | From a linked article on shift registers:
       | 
       | > To avoid these astronomical prices, some computers used the
       | cheaper alternative of shift register memory.
       | 
       | Might be a direction for 2026 too?
        
       | thakoppno wrote:
       | One theory I saw argued the punch card size was the reason for
       | 80x24. But why were punch cards that size? They were designed off
       | of the cards used for the census. Why were the census cards that
       | size? Because they were modeled after the dollar bill size.
       | 
       | I do love thought experiments like this but do believe they're
       | insatiably unresolvable.
        
         | ronsor wrote:
         | In the end, all reasons resolve to either "it's what we had at
         | the time" or "someone thought it looked good."
        
           | theamk wrote:
           | Not always, for example original CD disks had capacity of 74
           | minutes to accommodate Beethoven's Ninth Symphony.
        
             | rasz wrote:
             | That one also turned out a myth :) CD size was determined
             | by Cassette tape dimensions (diagonal, human can still hold
             | one in one hand) and that combined with conservative
             | pits/lands/track pitch choice drove the play time.
             | 
             | thus CD runtime was derived from something "what we had at
             | the time".
        
               | antiterra wrote:
               | The story as told may be inaccurate but it wasn't simply
               | 'what we had at the time' either.
               | 
               | The 74 minute length resulted from Sony rejecting the
               | Philips 60 minute 11.5cm diameter "Pinkeltje" disc size
               | in favor of a 12cm diameter.
               | 
               | It's quite possible that Sony's Norio Ohga simply argued
               | that the 9th symphony or various operas fitting would be
               | enough of an advantage for the slight size increase
               | without meaningfully decreasing portability.
        
           | rzzzt wrote:
           | "Everybody just liked it that way and it costs too much to
           | change it now": https://www.exocomics.com/743/
        
         | staplung wrote:
         | And the reason they were modeled after the dollar bill size is
         | because there were already many types of systems for storing
         | and organizing them. That came in handy for the census.
         | 
         | The old BBC Connections series has a segment with James Burke
         | using the old census tabulators.
         | 
         | https://www.youtube.com/watch?v=z6yL0_sDnX0&t=2640s
        
       | BirAdam wrote:
       | Man. I love the design of old terminals, computers, and such.
       | 
       | I am, also, extremely glad that these form factors were
       | abandoned. Having an old terminal, it is possibly the least
       | ergonomic machine I have ever used.
        
         | TacticalCoder wrote:
         | Same. And you may like this one:
         | 
         | https://design.tel/olivetti-tvc-250/
        
       | Animats wrote:
       | The PARC crowd thought displays should have the form factor of a
       | sheet of paper. Hence the Alto display.[1] That never caught on.
       | 
       | [1] https://www.righto.com/2018/01/xerox-alto-zero-day-
       | cracking-...
        
         | locallost wrote:
         | I see people doing that today.
        
       | thangalin wrote:
       | The linage can be traced back to Basile Bouchon's paper tape
       | invention in 1725. The article doesn't mention the role of
       | punched cards in The Holocaust, though, which my blog post goes
       | into:
       | 
       | https://dave.autonoma.ca/blog/2019/06/06/web-of-knowledge/
        
       | pezezin wrote:
       | Fascinating article, I really like knowing where the old
       | standards came from.
       | 
       | But I am extremely curious the first picture in the "The IBM 2260
       | video display terminal" section. All the other pictures show the
       | typical extremely round CRT of the era, but that one is the
       | characteristic cylindrical tube of Trinitrons, a technology
       | released several years later. I am trying to find some
       | information about it to no avail.
        
         | kens wrote:
         | The manual for the IBM 2260 describes the CRT in detail but I
         | don't think it has the information you want. My guess is that
         | if you're IBM, you can get the CRT in whatever shape you want.
         | 
         | [1]
         | https://www.bitsavers.org/pdf/ibm/2260/Y27-2046-3_2260_2848_...
        
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