[HN Gopher] LM8560, the eternal chip from the 1980 years
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LM8560, the eternal chip from the 1980 years
Author : userbinator
Score : 113 points
Date : 2025-11-02 04:27 UTC (18 hours ago)
(HTM) web link (www.tycospages.com)
(TXT) w3m dump (www.tycospages.com)
| rzzzwilson wrote:
| As an electronics experimenter I would have to say the REAL
| eternal chip is the 555 introduced in 1972. It's become a bit of
| a meme: You could have used a 555 for that!
|
| https://en.wikipedia.org/wiki/555_timer_IC
| iberator wrote:
| Highly agree
| geomark wrote:
| Yep. Just used a 555 today to whip up a low frequency clock
| source.
| tgv wrote:
| Or that opamp, the 741?
| gzalo wrote:
| Related video: stop using the LM741
| https://www.youtube.com/watch?v=e67WiJ6IPlQ
| rzzzt wrote:
| How about that 8 sound effects IC with the machine gun, bombs
| away, laser pew-pew, siren sounds?
| dreamcompiler wrote:
| 76477. I still have one on a board around here somewhere.
|
| https://en.wikipedia.org/wiki/Texas_Instruments_SN76477
| rzzzt wrote:
| I'm thinking of these ICs: https://www.reddit.com/r/AskEl
| ectronics/comments/a8af60/can_...
|
| One of the more famous toys using it (in blob form) is
| the Executor/Echo Keyller keychain:
| https://youtu.be/20W6AJuMjEk
| fhdkweig wrote:
| You can even make a rug out of it.
| https://www.righto.com/2025/09/marilou-schultz-navajo-555-we...
| ofalkaed wrote:
| The article bringing up flip-flop clocks reminded me of another
| mechanical digital clock that I can not quite remember the name
| of. It was from roughly the same time period as the flip-flop
| alarm/radio clocks but the numbers were wire grids or cutouts in
| wire grids and as the numbers changed they sort of faded from one
| digit to the next. I can't quite remember how the mechanism
| worked and the only clock of this sort I have ever seen was the
| one I bought ~20 years ago just to take apart and see how it
| worked. Anyone know what I am talking about?
|
| The mechanism was surprisingly simple once I got it opened and
| saw how it worked but from the outside made no sense, I probably
| stared at that clock for an hour trying to figure out how it
| worked before I finally opened it up to see what was inside. I
| might still have the clock mechanism in a box out in the garage.
|
| Edit: I suspect these clocks were actually from the time period
| at the end of flip-flops, showed up too late to become common,
| LEDs/LCDs killed them. The digits were on the dim side, perfectly
| fine for a bedside alarm clock and quite good for that situation
| but you had to be fairly close to clock to read it in a well lit
| room. Better than a flip-flop in a dark room but worse than an
| LCD in the light.
| kalleboo wrote:
| Nixie tubes worked as you describe but with the glowing
| elements inside a gas-filled glass bulb
| asdefghyk wrote:
| Maybe Vacuum Fluorescent Displays?
|
| as mentioned on https://www.youtube.com/watch?v=FH6LzV8FaEw and
| https://en.wikipedia.org/wiki/Vacuum_fluorescent_display
| ofalkaed wrote:
| The brightness of the clock was about the same as a tired old
| VFD that has consumed most of its phosphor but this was
| something much simpler and something anyone could figure out
| how it worked once they saw the insides. The general look was
| closer to the nixie tubes the other commenter mentioned but
| these grids did not emit the light, the light source was a
| standard bayonet base bulb or two behind the mechanism. I
| think the smoked plastic on the front was also part of how it
| worked, it acted as a filter and without it you saw
| everything but the numbers you wanted to see.
|
| Might have to go dig into that box in the garage and see if I
| still have it. I had intended on making a stand alone clock
| from it; the radio is not very good and the case has seen
| better days, so I was going to make a case for just the clock
| mechanism, perhaps its time.
| estimator7292 wrote:
| There are projection-type digit displays. I can't seem to
| find a picture at the moment, but these had an array of
| incandescent bulbs which project the image of the digit
| onto an internal screen. The timeline seems about right,
| this was peak Apollo era tech.
|
| There's also nixie and numitron tubes, as well as some neon
| digit displays. If it wasn't a tube, maybe it was a nixie-
| like display with a stack of acrylic plates each
| illuminated by an individual bulb.
| ofalkaed wrote:
| Went out into the garage and dug it out, it is a Telechron
| Mechanical Occlusion Display, here are a couple videos. First
| does a good job of showing how it looks when time changes,
| second is a 12 hour stream for the diehard.
|
| https://youtu.be/r9VA15DzX9k
|
| https://youtu.be/NLuRMLqI6C8
| cornholio wrote:
| Great passion for the subject, definitely doesn't get discouraged
| by their less than perfect command of English and didn't use an
| LLM to butcher the text's authentic character.
|
| I find that in my own writing I no longer strive for perfect
| grammar and polish since nowadays it actually cheapens the end
| result, everybody has perfect grammar today.
| sowbug wrote:
| Waaay off topic, but does anyone know why LLMs don't have poor
| grammar if they were trained on the average/poor grammar of the
| internet? Why don't they mix up then/than or it's/its, or use
| hypercorrections like "from you and I"?
|
| (Update: of course I had to ask my friendly neighborhood LLM,
| and the answer is the correct usages still dominate incorrect
| ones, so statistics favor correctness. They down-weight low
| quality sources (comments like mine) and up-weight high quality
| ones (published books, reputable news sites). Then human
| reinforcement learning adds further polish.)
| tuetuopay wrote:
| I would also expect a grammar phase to be part of the
| training, with an RL pass where the output is fed to a
| grammar check engine.
| omneity wrote:
| Two phenomena at play, correct spellings tend to be the most
| common on aggregate in a large enough dataset so there's a
| bias, and the finetuning step (Instruct SFT) helps the model
| hone down on what it should use from the set of all possible
| formulations it saw in pretraining.
|
| This is why LLMs can still channel typos or non/standard
| writing when you ask them to write in such a style for
| example.
| Waterluvian wrote:
| A retro red LED clock actually _adds_ to the calm atmosphere of
| my bedroom. I can't really sleep without one now.
|
| On the other hand, the only saving grace about my bright green
| and blue LED router is that someone whose hand should be shaken
| thought to allow software disabling or even a scheduled disabling
| of the LEDs.
| jrmg wrote:
| Yes! I actually bought one recently after staying in a hotel
| room that had a (recent - clearly a design choice) alarm clock
| with a big, dim, red LED display.
| gblargg wrote:
| One of the most interesting aspects it that it's all state
| machines and logic, with no CPU. This explains the weird
| glitches, e.g. having to not release one button while pressing
| another to avoid erroneous time setting. It shows what we take
| for granted that's trivial to do in software.
| mesrik wrote:
| Hah, what a coincidence this post is.
|
| Just last week I had to open first time alarm clock with green
| 7-segment display. Because I accidentally dropped it while
| vacuuming and antenna cord broke as it was so firmly under
| picture frame holding nail. And while open cleaned interior from
| dust, used greasy PRF to lubricate pots, switches and tuning
| wheel. If I recall correctly it did have that LM8560 chip in int
| and with display looked almost exactly what was in subject
| article inside.
|
| Label on bottom claims: -----------------------------
| Luxor CR 9016 NOKIA Consumer Electronics
| International S.A (FI)(N)(S)[x] 230V ~ 50Hz
| Battery 9 V MADE FOR NOKIA IN CHINA
| -----------------------------
|
| And another smaller sticker SERIAL NO.
| 9302-00106
|
| I bought -85 before christmas because my then girlfriend told
| that alarm clock that I've built myself using standalone clock
| module purchased from a local electronics component store was too
| ugly for us and had to go. Sure, I took that old one to summer
| cottage and once I saw this better looking to make her happy.
| What couldn't a young man do to make is becoming fiance happy,
| right.
|
| Q: But why the device is branded Luxor and it's made for NOKIA?
| A: Because NOKIA bought bit earlier that year (1985) Swedish
| Luxor consumer electronics. And I guess they did not had yet time
| redo chassis with NOKIA printed on and this was a still products
| transition period.
|
| NOKIA was still at that time making also TV sets and was about to
| bring two years later its first completely new way of
| implementing analog TV using digital processing chips, which
| allowed quite nice fieatures like PIP which was great help making
| VHS recording without ads. I had one of those TV-sets (M-model)
| and used it about 10 years.
|
| But that alarmclock radio from -85 is still going strong, good
| shape and it definitely was good purchase about 40 years ago.
|
| e: Sorry about formatting, I tried to find how to format
| literally, but couldn't find. OK, good enough now.
| dvh wrote:
| This summer I've made indoor (no direct sunlight) solar powered
| kitchen timer and I used STM32L011, it's winter and it's still
| working and voltage is stable. The power consumption is 100-150uA
| (28uA for display, 80uA for mcu, the rest is 1.2-to-3V boost).
| But it's only on when I cook (maybe 1h a day).
|
| https://imgur.com/a/ME1tx2c
| picture wrote:
| Very cool. Though it's unfortunate that most DIY electronics
| projects end up looking like IEDs, mine included
| lazide wrote:
| Well, IEDs are certainly a type of DIY electronics project?
|
| If they weren't improvised, they'd be factory explosives
| devices (FEDs) after all?
| Scoundreller wrote:
| Haha, the main meshtastic discord has a #notabomb channel for
| those sharing their DIY builds
| timonoko wrote:
| On that note. I tried to make candle replacement out of yellow
| LEDs in the 1980-years. To read books in de tent. But no matter
| how many leds I added it just was not enough.
| anthk wrote:
| Then in the late 90's and early 00's you almost got alarm clock
| at "Dollar Stores" for $15, and for really cheap pocket FM
| radios, you could get them as prizes with sodas and such, as a
| marketing scheme, with the soda logo printed in the device.
|
| With no internet, often you were in
| $REMOTE_FORGOTTEN_RURAL_VILLAGE and the TV antenna didn't have
| tons of nearly TV repeaters/relays, you would love some FM/AM
| radio with cool stations reaching over 100 and 200 kms in case of
| AM ( I remember to listen heavy metal/gothic metal stations from
| Portugal in Spain within 100 kms from the border ). In Spain,
| either boring national and international pop radioformula, or
| soccer past dinner everywhere.
|
| Oh, btw, one thing I hated from these clocks it's having to reset
| the time because it was misconfigured on a power cut. Nowadays
| they could just put some firmware and flash it for 0.0001 euros
| per device, if not less.
| Scoundreller wrote:
| I think some more advanced ones ran an internal "UPS" on 9V.
|
| Effectively a relay that would be held by mains and fail to 9V
| if the power went out with some replacement 60hz signal.
|
| As I recall, it would run the sound alarm but not the display.
| EvanAnderson wrote:
| I was excited to see the features of the chip that most clock
| manufacturers left undocumented described. There were a few I
| wasn't aware of and I'm going to try them on a vintage clock. I
| remember doing the hour/minute while holding alarm to reset the
| alarm to 0:00. I found that when I was a kid and thought it was
| so cool to discover a feature.
| chiph wrote:
| In high school I had one of the mechanical "flip" clocks. Then
| later an LED clock which almost certainly used the LM8560 (a
| Sony, which lasted far longer than I expected. Back when products
| were built with quality in mind). And as the article says, the
| chip depends on the AC frequency (50/60 Hz) to keep accurate
| time. For the US market, that input was likely hardwired to 60 Hz
| via a jumper. Japan must have used a switch, given it's mixed
| 50/60 Hz national power standard.
|
| These days I have an LCD clock that does not use the LM8560 but
| instead gets it's time from the Radio Data System values embedded
| in the FM broadcast. Possibly using the Sanyo LC72723 to decode
| them. The CT (clock Time & Date) data field is accurate to within
| 100ms according to wikipedia:
|
| https://en.wikipedia.org/wiki/Radio_Data_System
| amelius wrote:
| > "Digital" doesn't mean necessarily "electronic". It means that
| the time is show actively by digits and not by hands.
|
| Kind of weird since digitus means finger.
| fortran77 wrote:
| I remember how badly these radios would drift off-time when
| running on the battery backup! He explains in the article about
| how the back-up oscillator is a simple R-C circuit because the
| power line reference is absent.
|
| It would also kill the backup battery in a couple of hours. If
| you're in an area with prolonged, frequent backups it wasn't
| worth installing the battery. It was only good for occasional,
| short blackouts of a few seconds or less.
| Scoundreller wrote:
| Probably didn't help that your 1980s and 1990s 9V battery was
| likely a zinc-carbon battery, about 1/2 - 1/5th the mA of
| alkaline.
|
| I do remember that I could unplug and replug my alarm clock
| pretty quickly and it wouldn't lose its time if I needed to
| move sockets. Yay capacitors?
| RicoElectrico wrote:
| Being not a programmed micro controller, the LM8560 is also a
| virtually eternal component. Many modern micro controllers
| incorporate a flash memory to store the software that let the
| controller work and execute the desired functions. Flash memories
| retain their content not for an unlimited lifespan. It may be
| several decades, but before or later it comes the day when they
| begin to lose their content, and the micro controller stops to
| work. This can't happen to LM8560, because it doesn't contain any
| flash memory.
|
| That's a strawman, as the cheapest devices using microcontrollers
| use mask ROM.
| userbinator wrote:
| Mask ROM is actually starting to become less common as the
| price of OTP flash has dropped significantly, and changes can
| be implemented without paying for a new set of masks.
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(page generated 2025-11-02 23:01 UTC)