Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Show HN: Rotary Phone Dial Linux Kernel Driver

gitlab.com

Post reply on HN
Print view View original

41–50 of 51 posts

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#41

Post by johnea »

anonymousiam wrote: post #39
jtwaleson wrote: post #30

Earlier quoted context omitted.

Cool story :) out of curiosity, do you program those kind of things on the calculator itself? I did that with the hp49g and was proud of the programs I was able to write in such a constrained environment, but the single line display of the 41c would be a real achievement!

Thanks for asking. Yes, the calculator itself was the first "computer" that I owned, and there was nothing else to connect it to, or to emulate it with. (I had my own PDP-11 at work, and I had previously done batch-mode programming on an IBM 370.) I bought my 41C in 1979 (made in the US!), and spent several thousand dollars on peripherals over a period of about three years. It was a big investment in a platform that…

To this day, I still use a linux desktop simulator for the HP-41CX calculator!

The original website seems now offline:

https://nonpareil.brouhaha.com/

But the code is still available:

https://github.com/brouhaha/nonpareil

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#42

Post by anonymousiam »

johnea wrote: post #40
anonymousiam wrote: post #10

Back in the late 70's, I made a rotary phone dialer for my HP41C calculator. I connected a NC reed relay to the piezoelectric beeper and put the NC contacts in-line with my telephone line. I used "synthetic programming" (undocumented opcodes) to get the short duration beeps needed for the dialing pulses. I could enter a name (alphanumeric!) and it would look up and dial the phone number. About 10 years ago, I met a g…

A friend and I also made this! We used it as a speed dialer that worked on any phone. I still have the hard copy of the synthetic programming guide! Even outside of that technique, the calculator was a very powerful programmable tool for the early 1980s. The same friend and I also wrote a program for performing all of the calculations for a grad class in S-parameter modeling of RF transmission. We were so proud, we s…

Great stories. I had a similar experience with one of my college math professors (I was 16). I showed her that my calculator (with the Math module) could transform a 9th order matrix in a few seconds. She shrugged, because she knew that I didn't need the calculator to ace her tests.

The dialer was one of only two mods that I had made to my 41. I brought out the piezoelectric wires via a two-pin female .1" "berg" connector that I had added to the lower right side of the case. (I wish I had a photo.) The other mod used similar hardware; I put a magnetic reed switch inside, which changed a capacitor value for the system clock when a small magnet was attached (via Velcro) to the side of the calculator. The result was that my 41 would run its programs twice as fast. I had to remove the magnet to use my auto-dialer, because otherwise the timing was wrong. In my area, GTE didn't switch to ESS for another 10 years. Oh the fun!

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#43

Post by anonymousiam »

johnea wrote: post #41
anonymousiam wrote: post #39

Earlier quoted context omitted.

Thanks for asking. Yes, the calculator itself was the first "computer" that I owned, and there was nothing else to connect it to, or to emulate it with. (I had my own PDP-11 at work, and I had previously done batch-mode programming on an IBM 370.) I bought my 41C in 1979 (made in the US!), and spent several thousand dollars on peripherals over a period of about three years. It was a big investment in a platform that…

To this day, I still use a linux desktop simulator for the HP-41CX calculator! The original website seems now offline: https://nonpareil.brouhaha.com/ But the code is still available: https://github.com/brouhaha/nonpareil

I use the "realcalc" Android app. I first purchased it for PalmOS sometime around 1999. It's an absolutely fantastic emulator. I use Free42 on my iPad.

For the desktop, bc works fine for me.

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#44

Post by Stratoscope »

This reminds me of a rotary phone experience I had about 30 years ago.

It didn't involve a rotary phone directly, but a telephone network that was still compatible with them.

Rather than repeat the story, I'll link to it here:

https://news.ycombinator.com/item?id=40391220

If anyone needs their curiosity piqued, it involved a loud knock on the door and...

"San Jose Police! Open up!

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#45

Post by pram »

Stratoscope wrote: post #44

This reminds me of a rotary phone experience I had about 30 years ago. It didn't involve a rotary phone directly, but a telephone network that was still compatible with them. Rather than repeat the story, I'll link to it here: https://news.ycombinator.com/item?id=40391220 If anyone needs their curiosity piqued, it involved a loud knock on the door and... "San Jose Police! Open up!

FWIW I think all PSTN were/are compatible with pulse dialing.

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#46

Post by afandian »

spicybright wrote: post #14
mauvehaus wrote: post #8

When the iPhone was just a rumor, I suggested that making it with a touch wheel like the iPods of the time would be a great opportunity to bring back rotary dialing. This was soundly rejected by all present. Thanks to this, all I need to do is set up a Linux box so I can have that classic rotary vibe!

That would have been a hilarious timeline if they just upgraded ipods with cell networking, at least for one model. Then you can use this for typing: https://www.youtube.com/watch?v=9BnLbv6QYcA

And this a year or two before. Reflects how new some of these ideas seemed at the time.

https://m.youtube.com/watch?v=BGGOn-H7s3Q

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#48

Post by sephalon »

niccl wrote: post #34
bacon_waffle wrote: post #33

Fun historical twist: New Zealand rotary phones used a reversed mapping between digit and pulse count - here the number of pulses was 10-digit.

There was a deep technical reason for it, too. I suspect I'm one of the very few living people that know what it was., so I'll share it with HN so the knowledge doesn't die :-) A relatively early type of mechanical telephone exchange was the rotary exchange [0]. The pulses from the phone cause a clutch to connect the rotary driver in the exchange which then moved the switching stuff around (details can probably be in…

The driver supports alternate keycode mappings specifically for that reason, but before reading your comment I was unaware of the motivation behind reversing the pulse order. Thanks!

Re: Show HN: Rotary Phone Dial Linux Kernel Driver

#50

Post by satiric »

Stratoscope wrote: post #44

This reminds me of a rotary phone experience I had about 30 years ago. It didn't involve a rotary phone directly, but a telephone network that was still compatible with them. Rather than repeat the story, I'll link to it here: https://news.ycombinator.com/item?id=40391220 If anyone needs their curiosity piqued, it involved a loud knock on the door and... "San Jose Police! Open up!

That story rang a bell, and I was about to comment about 112 redirecting to 911 (precisely because 112 was easier to dial), then realized I had commented the same thing a year ago when I first saw the post
Post reply on HN