[HN Gopher] Mod. 5140 - IBM's First Laptop Computer
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Mod. 5140 - IBM's First Laptop Computer
Author : jumpocelot
Score : 75 points
Date : 2025-10-05 00:35 UTC (22 hours ago)
(HTM) web link (richardsapperdesign.com)
(TXT) w3m dump (richardsapperdesign.com)
| michaelsmanley wrote:
| When I was a co-op student employee at IBM in the late 80s, I was
| given a desk in what was otherwise a storage room piled with
| stuff that had been used and then set aside. One box contained a
| 5140 convertible laptop with one of each peripheral "slice" --
| printer, modem, expansion ports -- and the full set of technical
| manuals.
|
| I was allowed to take that beast home with me. I learned so much
| tinkering with that machine. Eventually, I sold the whole set at
| a ham fest and I have regretted it often.
|
| Nice to see an appreciation of it, though I would never have
| looked at it as alligator-like.
| lemonlearnings wrote:
| Any details to share re. specs, operating system?
| michaelsmanley wrote:
| That was almost 40 years ago, so little I recall other than
| it was an 8088 variant in there, the peripheral bus was
| unique to that machine and the only documentation was in the
| tech manuals (as opposed to the hardware reference book I had
| for everything else), and I got lucky and the lab had
| requisitioned a Model 2, so the screen was nice and they'd
| gotten the full 640Kb RAM.
|
| https://en.wikipedia.org/wiki/IBM_PC_Convertible has all the
| details on that machine you could want.
| reaperducer wrote:
| I had one. Great little system. Built like a tank, and just
| as heavy.
|
| Incredibly forward-thinking modular architecture. Keyboard,
| memory, drives, serial port, parallel port, even the screen
| could be replaced just by the turn of a lever or a push of a
| button.
|
| Fantastic keyboard, even by today's laptops standards.
|
| Ate batteries like M&Ms. I almost always kept it plugged in.
|
| At the time, running it off the pair of 720k floppies was
| fine. I believe there was a hard drive option, but I never
| saw it.
|
| Its biggest weakness was the screen. There were backlit and
| CRT options, which were better and you could just pop off and
| in.
|
| The screen was grayscale CGA, but there was a TSR called
| SimCGA which would translate, so you could run EGA programs.
| johnDD wrote:
| I wonder if John Titor could have used this?
| mananaysiempre wrote:
| Nah, that would have been made by IBN, a completely different
| company.
| dirkt wrote:
| Unlike the IBN 5100 [1] (which I guess actually was IBM's First
| Laptop Computer), the 5140 ran MS-DOS, and couldn't emulate the
| IBM/360 ISA like the IBN 5100 could, so it would be useless for
| John Titor because you couldn't hack SERN with it.
|
| [1] https://en.wikipedia.org/wiki/IBM_5100
| sroerick wrote:
| Aesthetically this beats about 75% of the current laptop market.
|
| Would love to see some genuine creativity / cyberdeck type builds
| from laptop makers
| iancmceachern wrote:
| I'm down. I can design and build it, if there are folks out
| there who are keen to do the other aspects of a business please
| feel free to reach out.
| criddell wrote:
| Maybe you can answer this then.
|
| Back in the early 80's, Radio Shack made the TRS-80 Model 100
| laptop. It ran for 20+ hours on 4 AA batteries.
|
| A few years later, Psion came out with a series of small
| devices that ran on 2 AA batteries and got 30+ hours of
| runtime.
|
| With modern electronics and displays, could something like a
| model 100 be made that could run for hundreds or even
| thousands of hours on 4 AA batteries?
| mananaysiempre wrote:
| > With modern electronics and displays
|
| Wouldn't the second part work against the first? There's a
| lot of pixels you need to push to refresh a good modern
| display. I guess you could use a bad (as in low-res) modern
| display, but I wouldn't expect those to be particularly
| concerned with energy efficiency either, just cheap.
| raddan wrote:
| I would kill for an e-ink version. For a palmtop I don't
| think a high-res color display is necessary.
| ac29 wrote:
| Yeah, the above referenced TRS-80 Model 100 had a 240x64
| monochrome display with no backlight. No surprise it
| didnt use much power.
| criddell wrote:
| A low-res display would be fine. In fact the same display
| as the original Model 100 would be great.
|
| A sibling mentioned e-ink and that might be ideal. With a
| fast enough CPU and race-to-sleep scheduling, the machine
| would mostly be in a low power idle mode.
|
| I think the temptation for a lot of designers here would
| be to use Linux and I think that would be a big mistake.
| A custom, basic OS with a few simple programs like the
| Model 100 or Psion 5 had would be ideal, at least for me.
| Or maybe even something like FreeRTOS (like the Flipper
| uses) if it is low power enough.
| reaperducer wrote:
| _A low-res display would be fine. In fact the same
| display as the original Model 100 would be great._
|
| Use one for a while before you decide.
|
| I still use mine every couple of weeks for distraction-
| free writing, and to read the news. The display updates
| VERY slowly. So slowly that you don't have to be a very
| strong typist to get way ahead of it.
| criddell wrote:
| The display worked better 40 years ago. They lose
| contrast and responsiveness with age.
|
| My favorite calculator is an HP-28s and it too has become
| slow and hard to see.
| reaperducer wrote:
| _With modern electronics and displays, could something like
| a model 100 be made that could run for hundreds or even
| thousands of hours on 4 AA batteries?_
|
| The biggest problem is the screen. People aren't going to
| tolerate a 40x8 (320px x 64px) screen with no backlight and
| limited contrast.
|
| Putting a modern screen on it is going to eat power beyond
| your budget.
|
| The M100's refresh rate wasn't great, so replacing the LCD
| with an e-ink display would be comparable, except it would
| far more expensive.
| iancmceachern wrote:
| As others have noted, its the "modern display" that does
| it.
|
| From the wiki here:
|
| "Display: 8 lines, 40 characters LCD, twisted nematic
| (gray) monochrome, with 240 by 64 pixel addressable
| graphics. The screen is reflective, not backlit.[3] The
| screen was made by Sharp Electronics.[4] The LCD
| controllers are by Hitachi: (10) HD44102CH column
| controller ICs and (2) HD44103CH row driver ICs; the
| HD44102CH's provide the programmable hardware interface to
| software. The refresh rate is about 70 Hz (coarsely
| regulated by an RC oscillator, not a crystal)."
|
| It's not even backlit.
| criddell wrote:
| Surely a display of similar specs made today would draw a
| fraction of the power the similar panel from 1983 did,
| no?
| c-smile wrote:
| I used to have NEC MobilePro 900 like here:
| https://live.staticflickr.com/213/481422006_92cdaeb6ee_b.jpg
|
| I miss that form factor really.
|
| And BTW, I regret that WindowsCE is not the thing anymore. IMO it
| has the best development infrastructure out there backed with
| MSVC IDE.
|
| I classify OSes into two major groups: "writer OS" (all desktop
| OSes primarily) and "reader OS" (all mobiles). But there is a
| void in between for palmtop form factor devices.
|
| Sigh, probably its only me who needs this ...
| mananaysiempre wrote:
| Judging by eBay prices for Psions, you're not the only one who
| misses that form factor.
| davidgaleano wrote:
| You may like this: https://kingjim.us/products/pomera-full-
| suite-typewriter-for...
| rsolva wrote:
| Or a reMarkable with the addon keyboard!
| Waterluvian wrote:
| Were these truly meant to be "laptops" or just portable
| computers? I guess if they have a battery is a fairly clear
| discriminator.
| mananaysiempre wrote:
| This one has a lead acid battery in it (I'm guessing a sealed
| one), which I don't expect to enhance its lap-friendliness.
|
| What somewhat puzzles me about these early portables (also
| including e.g. the Macintosh Portable, sold 1989-1991, in a
| similar form factor) is the manufacturers' insistence on
| putting a (heavy) mains transformer inside the chassis. That
| could not have helped the weight, so I have to guess they
| didn't see it as a problem?..
| WillAdams wrote:
| There was a concern about folks losing the separate
| transformer, and a perception that a single device was
| better.
|
| One interesting solution to this space was GRiD making their
| battery and power supply the same size and form-factor ---
| when one was working at a desk, to save space the battery
| could be removed and placed in a separate charger, while the
| cord from the power supply to the computer was removed, and
| it was then placed in the battery compartment and connected
| to the wall, powering the device.
| reaperducer wrote:
| _What somewhat puzzles me about these early portables (also
| including e.g. the Macintosh Portable, sold 1989-1991, in a
| similar form factor) is the manufacturers' insistence on
| putting a (heavy) mains transformer inside the chassis._
|
| The transformer was outboard on this machine, like a modern
| computer. It had its own Velcro compartment in the carrying
| bag.
| sprior wrote:
| It came slightly after the IBM Portable PC (5155) which was
| released in 1984. That was a real luggable very similar to the
| Compaq. So I'd say the 5140 (which I've seen but never owned, I
| did think I was getting one once from a contest) was thought of
| as a luggable, but an improvement over what came before it.
| munchlax wrote:
| Sorry to wit but if it has a battery, it's called a notebook.
| Nowadays laptops _can_ be notebooks but not vice-versa.
| roryirvine wrote:
| Not really.
|
| Originally, there were portables (sometimes referred to as
| "luggable"), like the Osborne or Compaq Portable series. The
| early models were the size of a small suitcase or large
| briefcase and contained a CRT screen, usually with a
| detachable full-size keyboard.
|
| Later, portables ditched the CRT in favour of (very readable)
| gas plasma displays, allowing for greatly reduced depth. The
| final models were roughly the size of two shoeboxes stacked
| on top of each other, and were sometimes referred to as a
| "lunchbox".
|
| Laptops took the opposite approach, reducing height rather
| than depth. This IBM 5140 was a good early example, but I
| think the first might actually have been the Data General
| DG-1 in 1984.
|
| They had a flat screen (usually passive matrix) with a hinge
| directly behind the keyboard. About a third of the case stuck
| out behind the hinge, and typically housed the battery
| (usually lead acid), floppy disk, and HDD.
|
| Unlike the previous luggables, they could just about be used
| on a lap for short periods. They often weighed around 5-6kg,
| though, so most of them will have been used on a desk or
| table almost all of the time.
|
| Notebooks came a few years later (1989-ish), with the NEC
| Ultralite, Toshiba Dynabook, and Compaq LTE leading the way,
| and were distinguished by being smaller still - the size of a
| ream of A4 paper - and having the hinge right at the back of
| the machine.
|
| They tended to be lower-powered (8086 CPUs rather than 286 or
| 386), and initially only had a FDD as they were too small to
| fit a full-height 3.5" hard drive. They weighed around 2-3kg,
| so actually _could_ be used on a lap.
|
| The limitations of the smaller models evaporated quickly, and
| notebooks had almost completely taken over by the mid 90s.
| The last lunchbox portable was probably the Compaq 486 in
| 1992. There were still a few rugged or workstation laptops
| being produced right up to the end of the decade, but they
| were pretty rare by that point.
| munchlax wrote:
| Thanks. The PC magazines had me confused for decades
| mananaysiempre wrote:
| See also: "IBM Made the Longest Laptop Ever" by Cathode Ray Dude,
| https://www.youtube.com/watch?v=htl_JbZIcUU. There is, per the
| title, some discussion of its (somehow simultaneously inspired
| and silly) expansion system, but also of its other features as
| well, such as (spoiler alert) the fact that it may be the first
| personal computer to have suspend to RAM.
|
| (So I guess--expanding on a sibling comment[1]--aesthetics is not
| the only axis on which "this beats about 75% of the current
| laptop market.")
|
| [1] https://news.ycombinator.com/item?id=45478692
| dariosalvi78 wrote:
| I still have it at home, it was my first PC, my father bought it
| and never used. I learned using DOS on it
| prmoustache wrote:
| I'd argue that given the max angle of the screen it cannot be
| used on your lap comfortably unless your eyes are on your navel.
| Hence it would be a battery powered portable pc and not a laptop.
| shakna wrote:
| The TRS 80 Model 100 is regularly called "the first laptop".
| You'd disagree with that.
|
| Where's the line? Is a CHIP or M5 Cardputer portable or laptop?
|
| Is it the hinge needed? In which case is a folding phone, a
| phone, laptop, or tablet?
|
| (Not meaning to be aggressive. Curious about the fuzzy
| definition. Wanting to be convinced.)
| reaperducer wrote:
| _I 'd argue that given the max angle of the screen it cannot be
| used on your lap_
|
| I'd argue that the two years I spent using it as a laptop,
| largely on my lap, says it works fine.
|
| I also used it balanced on my knees, curled up in a window
| nook.
| WillAdams wrote:
| For the rest of the story, see:
|
| https://www.goodreads.com/book/show/483933.ThinkPad
| atombender wrote:
| I taught myself Turbo Pascal on a friend's IBM PS/2 P75 [1]
| around 1990, also a briefcase-style luggable that came out a
| couple of years after this one.
|
| The P75 had a delightful orange plasma screen, and the keyboard
| was wired and could be unhooked from the case, and since it was a
| 486 chip, it could all of DOS, OS/2, and Windows (and apparently
| it was able to run Windows 95 when that came out).
|
| My main machine at the time was the Amiga 500, and the PS/2 felt
| like a step down in terms of graphics and so on, but Turbo Pascal
| was just too magical for me to care.
|
| [1] https://en.wikipedia.org/wiki/IBM_PS/2_portable_computers
| theodric wrote:
| Hey, I just brought mine home! Got funny looks at TSA _and_ on
| the plane, but nobody stopped me :)
|
| Piccy:
| https://cdn.social.linux.pizza/system/media_attachments/file...
|
| (Link to post in case that doesn't work:
| https://social.linux.pizza/@theodric/115256647992228538 )
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(page generated 2025-10-05 23:02 UTC)