Casio F-91W, Going Dark

January 22, 2021 by Kristina Panos 19 Comments

The Casio F-91W is easily one of the most iconic and popular watches worldwide. But what’s cool about having the same exact thing as millions of other people? Not much, unless of course you modify it to make it your own. That’s exactly what [Gautchh] did to their beloved watch. Between permanent dark mode, stereo blue LED backlights, and a new strap, this timepiece really stands out from the crowd.

Once [Gautchh] got the watch open, the first order of business was to re-polarize the LCD with a different film so the digits are light and the background is dark. This watch ships with a single green backlight LED that’s fairly faint, so [Gautchh] upgraded it to bright blue and added a second 1206 LED in parallel on the other side of the readout. Finally, they replaced the rubber strap with something less likely to chafe.

We think dark mode looks great, though [Gautchh] says it requires a little bit of training to hold your wrist just right to make it readable. They make these mods look easy, but they likely aren’t for the faint of heart. If you want to give it a shot, there are good step-by-step instructions and several pictures to help out.

We’ve seen a lot of Casio F-91W projects over the years, including a method for waterproofing the internals. If you have a lot of love for this watch, why not make a giant version?

Casio Computer Rebuild Puts New Wine In An Old Bottle

September 18, 2020 by Mike Szczys 8 Comments

With a glut of vintage consumer electronics available from eBay it should be easy to relive your glory days, right? Unfortunately the march of time means that finding gear is easy but finding gear that works is not. So was the case when [Amen] acquired not one, but two used calculator/computer units hoping to end up with one working device. Instead, he went down the rabbit hole of redesigning his own electronics to drive the Casio QT-1 seen here.

Especially interesting is the prototyping process for the replacement board. [Amen] used a “BluePill” STM32 microcontroller board at its heart, and used point-to-point soldering for the rest of the circuitry on a rectangle of protoyping board. That circuit is non-trivial, needing a 23 V source to drive the original VFD from the computer, a battery-backed real-time-clock (MCP7940), and a GPIO expander to scan the keys on the keypad.

It worked great, but couldn’t be cut down to fit in the case. The solution was a PCB designed to fit the footprint of the original. The modern guts still need more firmware work and a couple of tweaks like nudging that 23 V rail a bit higher to 26 V for better brightness, but the work already warrants a maniacal cry of “It’s Alive!”.

This isn’t [Amen’s] first rodeo. Back in March we looked in on another vintage Casio refurb that sniffed out the display protocol.

It’s Time For Watch Clocks To Make A Comeback

July 10, 2020 by Kristina Panos 10 Comments

Along with all the colorful, geometric influence of Memphis design everywhere, giant wristwatch clocks were one of our favorite things about the 80s. We always wanted one, and frankly, we still do. Evidently, so did [Kothe]. But instead of some splashy Swatch-esque style, [Kothe] went the nerdy route by building a giant Casio F-91W to hang on the wall.

Not only does it look fantastic, it has the full functionality of the original from the alarm to the stopwatch to the backlit screen. Well, everything but the water resistance. The case is 3D-printed, as are the buckle and the buttons. [Kothe] might have printed the straps, but they were too big for the bed. Instead, they are made of laser-cut foam and engraved with all the details.

Inside there’s a 7″ touch display, a real-time clock module, and an Arduino Mega to make everything tick. To make each of the printed buttons work, [Kothe] cleverly extended a touch sensor module’s input pad with some copper tape. We think this could only be more awesome if it were modeled after one of Casio’s calculator watches, but that might be asking too much. Take a few seconds to watch the demo after the break.

Prefer your clocks less clock-like? Get a handle on the inner workings of this slot machine-based stunner.

Continue reading “It’s Time For Watch Clocks To Make A Comeback” →

DMCA Vs Hacker

May 30, 2020 by Elliot Williams 46 Comments

This week featured a large kerfuffle over a hack that you probably read about here on Hackaday: [Neutrino] wedged an OLED screen and an ESP32 into a Casio calculator. REACT, an anti-counterfeiting organization, filed DMCA copyright takedowns on Casio’s behalf everywhere, including GitHub and YouTube, and every trace of [Neutrino]’s project was scrubbed from the Internet.

The DMCA is an interesting piece of legislation. It’s been used to prevent people from working on their tractors, from refilling printer ink cartridges, and to silence dissenting opinions, but it’s also what allows us to have the Internet that we know and love, in a sense.

In particular, the “safe harbor” provision absolves online platforms like YouTube and GitHub from liability for content they host, so long as they remove it when someone makes a copyright claim on it. So if a content owner, say Casio, issues a takedown notice for [Neutrino]’s GitHub and YouTube content, they have to comply. If he believes the request to be made in error, [Neutrino] can then file a counter-notice. After ten to fourteen days, presuming no formal legal action has been taken, the content must be reinstated. (See Section 512(g).)

Both the takedown notice and counter-notice are binding legal documents, sworn under oath of perjury. Notices and counter-notices can be used or abused, and copyright law is famously full of grey zones. The nice thing about GitHub is that they publish all DMCA notices and counter-notices they receive, so here it is for you to judge yourself.

Because of the perjury ramifications, we can’t say that the folks at REACT who filed the takedown knowingly submitted a bogus request in bad faith — that would be accusing them of breaking federal law — but we can certainly say that it looks like they’re far off base here. They’re certainly not coders.

The good news is that the code is back up on GitHub, but oddly enough the video describing the hack is still missing on YouTube.

But here’s how this looks for Casio and REACT: they saw something that was unflattering to a product of theirs — that it could be used for cheating in school — and they sent in the legal attack squad. If that’s the case, that’s rotten.

Hackaday Podcast 069: Calculator Controversy, Socketing SOIC, Metal On The Moon, And Basking In Bench Tools

May 29, 2020 by Mike Szczys No comments

Hackaday editors Mike Szczys and Elliot Williams march to the beat of the hardware hacking drum as they recount the greatest hacks to hit the ‘net this week. First up: Casio stepped in it with a spurious DMCA takedown notice. There’s a finite matrix of resistors that form a glorious clock now on display at CERN. Will a patio paver solve your 3D printer noise problems? And if you ever build with copper clad, you can’t miss this speedrun of priceless prototyping protips.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

Continue reading “Hackaday Podcast 069: Calculator Controversy, Socketing SOIC, Metal On The Moon, And Basking In Bench Tools” →

DMCA Takedown Issued Over Casio Code That Wasn’t

May 24, 2020 by Jenny List 97 Comments

Earlier this month, we posted coverage of an ingenious calculator hack that took a Casio calculator and put an ESP8266 module and an OLED display in the space occupied by its solar cell. Controlled by a pair of unobtrusive Hall effect devices, the calculator could have been used as an ingenious cheating device but was to us the epitome of a well-executed hack. We may have liked it but it seems the folks at Casio didn’t, because they’ve issued a DMCA takedown notice for the project’s GitHub repository.

Editor’s Update: [Tom Fleet] reports that GitHub has completed the DMCA review and found the code repo does not infringe on Casio’s IP. However, it appears the copyright claim on the YouTube video has not been resolved and that video remains unavailable. However, that video is still available on the Internet Archive.

This is a picture of Barbra Streisand, who might almost be the patron saint of unintended consequences. Unknown author / Public domain.

We’re not lawyers, but if you’d care to visit our original coverage and watch the video in full, you’ll see that the ESP does not in any way tap into the calculator’s functions. The epoxy blob over the Casio processor is intact and no wires connect to the calculator mainboard, so it is difficult to imagine how any Casio code could have found its way into a repository full of ESP8266 code for the Arduino IDE. A quick search for “Hack-Casio-Calculator” on GitHub, at the time of publishing, turned up the relevant code despite Casio’s takedown, and we can’t see what they’re on about. Maybe you can?

Over the years there have been many attempts to use the DMCA on projects in our community. Some have been legitimate, others have been attempts to suppress exposure of woeful security, and still more have been laughably absurd. This one seems to us to edge into the final category, because it is difficult to see how the project described could contain any Casio code at all. It would be entirely legitimate to issue a DMCA takedown had the epoxy blob been removed and Casio’s code been retrieved from the calculator chip (and we’d certainly cover that story!), but as far as we can see taking a scalpel to a calculator’s case and stuffing a module behind the solar panel window does not come close.

It’s evident that Casio do not like the idea of one of their calculators being turned into a cheating device, and we understand why that might be the case. But to take the DMCA route has served only to bring more publicity to the affair, and those of us with long memories know that this can only lead to one conclusion.

Thanks [Tom] and others for the tip.

Adding MIDI To An Old Casio Keyboard

May 23, 2020 by Lewin Day 22 Comments

Not content to rule the world of digital watches, Casio also dominated the home musical keyboard market in decades past. If you wanted an instrument to make noises that sounded approximately nothing like what they were supposed to be, you couldn’t go past a Casio. [Marwan] had just such a keyboard, and wanted to use it with their PC, but the low-end instrumented lacked MIDI. Of course, such functionality is but a simple hack away.

The hack involved opening up the instrument and wiring the original keyboard matrix to the digital inputs of an Arduino Uno. The keys are read as a simple multiplexed array, and with a little work, [Marwan] had the scheme figured out. With the Arduino now capable of detecting keypresses, [Marwan] whipped up some code to turn this into relevant MIDI data. Then, it was simply a case of reprogramming the Arduino Uno’s ATMega 16U2 USB interface chip to act as a USB-MIDI device, and the hack was complete.

Now, featuring a USB-MIDI interface, it’s easy to use the keyboard to play virtual instruments on any modern PC DAW. As it’s a popular standard, it should work with most tablets and smartphones too, if you’re that way inclined. Of course, if you’re more into modular synthesizers, you might want to think about working with CV instead!