2026-05-22 00:32:57 <KipIngram   > Oh my gosh.  I'm watching a history "counterfactual" - what if Japan hadn't attacked Pearl Harbor.  This dude who was a rear admiral in the US Navy just said "If they hadn't attacked a state of the United States..."  I.e., that it was a "higher offense" somehow than attacking the Philippines.  But Hawaii wasn't a state until 1959.  It was a territory, same as the Philippines.  Good grief.
2026-05-22 07:25:00 <xentrac     > KipIngram: also the US was already blockading Japan's oil imports
2026-05-22 10:04:20 <veltas      > Agreed, US foreign policy intentionally provoked Japan, although Pearl Harbor was a particularly cowardly move by Japan
2026-05-22 10:05:41 <veltas      > But the US, the UK, and everyone knew Japan would attack, and this was desirable to the US leadership that wanted to get involved in the war but couldn't justify it because it was highly unpopular among the general population
2026-05-22 10:06:17 <veltas      > And was desirable to the UK which is why we supposedly didn't share intelligence we had on Japan's plans
2026-05-22 12:26:08 <Stalevar    > Why calculators with RPN cost about the price of medium-range laptop?
2026-05-22 12:30:21 <veltas      > Sometimes when I see half-decent laptops from like 5 years ago selling for about 50 GBP I wonder what the point of any kind of special small computing device is
2026-05-22 12:30:29 <veltas      > On like eBay
2026-05-22 12:30:56 <cleobuline  > hello !
2026-05-22 12:40:22 <veltas      > Hi
2026-05-22 12:49:47 <Stalevar    > veltas, you can't put into pocket
2026-05-22 12:50:04 <Stalevar    > but you can install Free42 or termux with dc on smartphone
2026-05-22 12:52:08 <veltas      > Yup
2026-05-22 12:53:09 <veltas      > And then there are cheap raspberry Pi style things which can do GPIO etc if you want to play with low level peripherals, and they can run a thousand calculator OS's at once
2026-05-22 12:53:23 <veltas      > Not a raspberry Pi itself because those are overpriced
2026-05-22 12:53:39 <veltas      > But like a cheap SBC
2026-05-22 12:58:21 <Stalevar    > You can use any stm32 or esp32 board instead
2026-05-22 12:58:31 <Stalevar    > Much cheaper and easier on power
2026-05-22 12:58:52 <Stalevar    > though probably not enough GPIO for each button
2026-05-22 13:00:10 <veltas      > Could use button matrix
2026-05-22 13:28:46 <MrMobius    > DM42 runs for months and months on a coin cell
2026-05-22 13:28:56 <MrMobius    > unlike rpi
2026-05-22 14:38:41 <KipIngram   > Stalevar: If you organize the keys into an electrical grid so that when you push one you activate one row and one column, then you can cut way down on the GPIO required.  My DM42 has eight rows and five or six columns, so 14 bits of GPIO could handle it.
2026-05-22 14:39:08 <KipIngram   > The software would read active row and active column and map that to a key.
2026-05-22 14:39:46 <KipIngram   > It's perfect for a calculator since you never activate two keys at once.
2026-05-22 14:40:28 <Stalevar    > KipIngram, you got Swiss thing?
2026-05-22 14:40:38 <KipIngram   > Yes, love it.
2026-05-22 14:40:46 <Stalevar    > I was wondering if it really worth cost of a new laptop
2026-05-22 14:40:51 <KipIngram   > I think they have a newer version of it now - mine is a generation back.
2026-05-22 14:41:26 <KipIngram   > Well, a low-end laptop, but yeah; I get your point.  I just have some nostaligia for my college days  (HP-41CV then).
2026-05-22 14:41:45 <KipIngram   > So I've made a conscious effort to use it for things, and it's something of a habit now.
2026-05-22 14:41:59 <KipIngram   > Though I've by no means really pushed its envelope.
2026-05-22 14:43:51 <Stalevar    > KipIngram, the new version only changes µUSB to Type-C and CPU is faster (but slowed down when on battery)
2026-05-22 14:44:18 <Stalevar    > KipIngram, so how does it compare to GNU dc or Forth?
2026-05-22 14:53:36 <veltas      > KipIngram: The grid is what I mean by a matrix
2026-05-22 14:55:04 <veltas      > What's fun is allowing multiple key presses, and rejecting multiple presses when you can't determine the correct key, in Z80 assembly
2026-05-22 14:55:56 <veltas      > Which I think I've written multiple times now, the ZX Spectrum's I/O port lets you see the rows/columns currently shorted
2026-05-22 14:56:31 <veltas      > And if you don't reject indeterminate presses then if you type badly it will just input seemingly random letters you didn't touch
2026-05-22 14:56:53 <veltas      > If you don't allow determinate multiple presses then you can't really type quickly
2026-05-22 14:57:16 <veltas      > So it's not really "fun" and more "table stakes" for the ZX Spectrum
2026-05-22 15:00:24 <Stalevar    > veltas, I bought a Z80 and arduino and lots of leds and switches but didn't start anything yet.
2026-05-22 15:01:08 <Stalevar    > I was wondering how hard would it be to build a simple computer like IMSAI or Altair but without fluff like S100 and extensibility, just RAM, CPU and control panel
2026-05-22 15:01:35 <Stalevar    > And Z80 is cheaper than i8080 and easier to wire because only one voltage
2026-05-22 15:03:46 <veltas      > Huh just realised that the parity bit would be a good way to check for indeterminate presses in most cases
2026-05-22 15:04:06 <veltas      > Imagine that, a useful parity bit (beyond like transmission error detection)
2026-05-22 15:30:40 <MrMobius    > you might get a function key like 2nd or shift pressed on a calculator while another key is pressed
2026-05-22 15:31:47 <MrMobius    > with multiplexing like that, you get a 4th "phantom" key that appears pressed when the other three keys that would make a square pattern are pressed
2026-05-22 15:32:01 <MrMobius    > not that that would happen often
2026-05-22 16:15:54 <veltas      > Is it just me or are LLMs outputting worse and worse answers?  I feel like they're all in a race to the bottom, I am guessing to save money and appear more profitable or something?
2026-05-22 17:34:34 <Stalevar    > MrMobius, usually you press shift or 2nd on calculator and then press the function key, not simultaneously
2026-05-22 17:34:53 <MrMobius    > depends on the calculator
2026-05-22 17:35:16 <Stalevar    > I don't think I ever seen a calculator where you have to press and hold
2026-05-22 17:36:56 <MrMobius    > another question is if the user might hold the key even if it's not necessary and what you'd do then
2026-05-22 21:01:10 <xentrac     > Stalevar: calculators with RPN are costly because their target market is middle-aged and elderly engineers in the US, which is a small market, so the non-recurring engineering costs are distributed over a small number of sales.  Fortunately it's also a rich market or the product wouldn't exist at all
2026-05-22 21:01:52 <xentrac     > half-decent cellphones from 5 years ago that you can install PostmarketOS on are maybe a closer equivalent to pocket calculators
2026-05-22 21:02:39 <xentrac     > they don't run for months and months on a coin cell, but they will hold a charge for a few days when you recharge them
2026-05-22 21:05:03 <xentrac     > KipIngram: if you *never* activate two keys at once, and your GPIOs support tristating (like, anything better than an 8051's "quasi-bidirectional" I/Os) you can handle the 42 keys you're talking about with 7 pins rather than 14 with https://en.wikipedia.org/wiki/Charlieplexing
2026-05-22 21:06:48 <xentrac     > Stalevar: simple computer like IMSAI or Altair but without fluff like S100 and extensibility sounds to me like an AVR microcontroller connected to a battery