Pimping My Casio: Part Deux

163 r4um 45 7/19/2025, 7:58:26 AM blog.jgc.org ↗

Comments (45)

RubenSandwich · 3h ago
Love to see the simulator screenshot. I was the one who added simulator support for the custom LCD: https://github.com/joeycastillo/second-movement/pull/26.

There is a very active discord community around the sensor watch. Come join us; https://discord.gg/Rdd9ewREaJ. I'm currently working on adding step counting support to the sensor watch pro. (Also I'd appreciate the help in getting a low power and low computation cost step counter working, which is a bit hard when your battery budget is a CR2016.)

thebruce87m · 11h ago
> Since I bought the optional accelerometer add on it's necessary to put in place a little piece of caption tape

This should be _Kapton Tape_ https://croylek.com/pages/kapton-tape?srsltid=AfmBOoqVfkbfaW...

jgrahamc · 11h ago
Argh. Motherducking autocorrect!
rtaylorgarlock · 4h ago
In context, anyone who needs to understand almost certainly got it. Right? I haven't heard of 'caption tape', but I definitely have seen lots of misspellings of 'kapton' in context. :D
maxglute · 5h ago
very cool. casio would make killing building fitness band with 3-4 week battery life in the form factor of f91w. cheap fitness bands are basically already the mass smart watches of our era.
orkj · 4h ago
maxglute · 34m ago
Yeah. This and GShock Move. IMO pretty low effort, I'd want basic smart watch / band functions like full sensor suite, notifications, nfc. Literally just need Casio to copy a miband (which goes on sale for like <30 USD) / or fitbit and slap it in affordable f91w style body. TBH part of me feels sad / thinks JP electronic decline = they're simply not capable. Fingers crossed for day Casio figures out f91w shaped smartband/watch where the buttons can control media or be programmable like pebble. I'd pay 200+ for fancier housing, but not watch+pedometer.
Sophia95 · 7h ago
Clicked on this thinking it was about a calculator, so impressed that it was about swapping out the guts of an casio watch and building and uploading the firmware.
jgrahamc · 5h ago
nan60 · 2h ago
I have wanted this for forever. My dream watch is the F91-W, but with weather as well. I cannot wait to try this out.
teruakohatu · 12h ago
I have been reluctantly holding off hoping they will come out with a dot matrix or epaper screen. Neither will probably ever happen but I can dream.
simgt · 12h ago
teruakohatu · 1h ago
That is exactly what I want! Thank you for sharing the link.
andoando · 4h ago
Oh this looks awesome
beefsack · 12h ago
I absolutely loved my Pebble. It was so amazing in its own niche.
mbirth · 12h ago
You do know that Pebble is back from the dead?

https://repebble.com

Disposal8433 · 11h ago
> git clone --recurse-submodules [...]

Small improvement but it should get the clone and the submodules at the same time.

wronex · 4h ago
I really like that USB port. It can probably be made to work in both directions (like USB-C). Does it require a special PCB thickness that is hard to come by?
ajsnigrutin · 14h ago
TSA: "Sir, are you wearing the terrorist watch?"

You: "no no, it's a modified terrorist watch, it now has more features!"

https://www.spiegel.de/international/world/al-qaida-s-watch-...

https://www.watchesofespionage.com/blogs/woe-dispatch/casio-...

jgrahamc · 13h ago
dustypotato · 13h ago
brb gotta buy a casio lineage watch now
rwmj · 9h ago
IMO the Casio Oceanus S100 is a better watch in that category - solar powered, radio-controlled, waterproof, no apps or connectivity, but more dressy. However it's JDM only so you have to order it off eBay (or buy it on a trip to Japan I suppose).
Findecanor · 6h ago
The Sensor Watch wiki lists several other compatible Casio watches [1] that all came with a Casio Module 593. Several have a metal finish, or even a round case. The module number is etched on the steel back.

All modern compatible watches from Casio are made of plastic: black or chromed plastic. Only some vintage models are in real metal. Vintage watches that came with modules 451, 587, 590 or 595 (maybe more) will also fit a module 593, but you'd still have to source a module 593 for its plastic chassis and other parts. Also, just the other week there popped up a steel replacement case for sale on AliExpress, which as been confirmed to work fine.

I bought a vintage Casio W-34 (Module 590) just for my Sensor Watch because I wanted one of steel and because it resembled my broken A158W that I had used for years.

1. https://www.sensorwatch.net/docs/#need-to-buy-a-watch

_false · 14h ago
What's the process of adding sensors to the custom motherboard? Based on your watchface config it looks like you added accelerometer. I wonder what other sensors are easy to add. I'd love to have an hrm in mine
ethan_smith · 1h ago
The SensorWatch platform supports I2C sensors that fit within the watch's tight power and space constraints - beyond accelerometers, temperature/humidity, pressure, and ambient light sensors work well, but HRM would likely draw too much power for the CR2016 battery.
jgrahamc · 13h ago
throwanem · 11h ago
Admittedly my watch only gets 1/50 the battery life and doesn't pick up WWV. On the other hand, being able to redesign its face in Emacs and Illustrator and update it OTA makes up for a lot. So does not having to wear a molded polymer bracelet - those things are awful!
BenjiWiebe · 9h ago
What's wrong with molded polymer bracelets? I assume you're referring to the wristband? I've really only worn one watch and it has a molded polymer wristband, and it doesn't bother me, but maybe I'm missing out on something nicer.
guestbest · 4h ago
Was there ever a version of this that would run a full blown DOS?
neom · 11h ago
This, is how to enjoy your retirement. Hope we see lots of other fun projects like this from you John, a very enjoyable read. :)
jgrahamc · 10h ago
This is a really simple "project" because someone else did all the work! I just had to install the thing and make some tiny code modifications for my taste.
justmarc · 13h ago
Very cool! What's the expected battery run time?
jgrahamc · 13h ago
See: https://www.crowdsupply.com/oddly-specific-objects/sensor-wa... Answer: 1 to 2 years. My previous watch from the original blog post is still running on the original battery.
justmarc · 13h ago
Thank you, John.

Coincidentally, your web site https://jgc.org/ is truly a lovely example of https://news.ycombinator.com/item?id=44613625 which was just discussed today as well.

Love your behind the screens stuff!

jgrahamc · 13h ago
Thanks! Glad you enjoy https://behind-the-screens.tv. Those videos were an enormous amount of work because of all the original research behind them. I do have one more I'd like to do about this film: https://www.rottentomatoes.com/m/defense_play_1987 One day perhaps!
justmarc · 13h ago
Oh I don't doubt it! I was thinking how does such a busy man have time for this... but we always have time for passions and side projects :)

The airwolf one was funny, since it was a childhood favorite, and what a funny little typo they had there.

When watching the video I was thinking to myself, could this series have influenced my future interests in ways I didn't even know? Fun.

jgrahamc · 11h ago
The key to doing things when you're very busy is to do them slowly and not drive yourself crazy with a deadline. When I did the ThinkPad 701c restoration it took me a year!
justmarc · 10h ago
Old Thinkpads were truly glorious machines. Top notch engineering and materials.
eabeezxjc · 13h ago
is any Linux version? I'm not using brew
jgrahamc · 11h ago
Windows, macOS and Linux instructions here: https://www.sensorwatch.net/docs/movement/building/
teruakohatu · 13h ago
Brew run on Linux just as well as on MacOS.
mikae1 · 9h ago
It’s actually the default package manager for uBlue distros.

I’ve used it as my only package manager on Linux for a few years and I love it.

snozolli · 7h ago
Reminds me of the Texas Instrument Chronos, which was a watch that existed solely to promote the MSP430. I think it was released around 2013. Looks like it's no longer in production, but you can find them used around $40.
zippyman55 · 9h ago
Respect.
TMSai · 14h ago
This is a brill project