A first-generation car phone connected to a piece of prototype board with a BlueTooth module

Custom Bluetooth Adapter Brings 1990s Car Phone Back Online

April 13, 2023 by 20 Comments

[Jeff Lau]’s Mitsubishi 3000GT comes with all the essential features you’d expect in a fancy sports car from 1993: pop-up headlights, movable spoilers, and a fully-functional telephone handset in the center console. The phone was fully functional until North America’s first-generation AMPS cellular network was shut down back in 2008, since then, it hasn’t done much but show “NO SVC” on the display. That is, until [Jeff] decided to build a Bluetooth adapter that lets it connect to a modern smartphone.

The easy solution would have been to simply connect the handset’s speaker and microphone to a standard Bluetooth headset, but that would have destroyed the 1990s aesthetic it had going on. So what [Jeff] did instead was construct a plug-in module that hooks up to the phone’s base station in the trunk and communicates directly with all the existing systems. That way, the phone works in exactly the same way it always did: the radio is automatically muted during calls, the buttons on the steering column work as expected, and you can even dial and store numbers using the buttons on the handset.

A car phone base station and wiring in the trunk of a Mitsubishi 3000GT
No modifications required: the BlueTooth module is connected using the factory-installed cabling

It took a lot of reverse-engineering to figure out the technical details of the DiamondTel Model 92 that came with the car as a factory option. [Jeff] helpfully documented all of his findings on the project’s GitHub page, making it easy for anyone with a similar system to implement their own upgrades. The main components of the upgrade kit are a BM62 Bluetooth module that connects to a modern phone, a PIC18F27Q43 microcontroller to implement the car phone’s interface and menus, and several analog chips to process the audio. All of these are mounted on a piece of prototype board and housed in a standard plastic enclosure that neatly fits on top of the existing equipment in the trunk.

While the hardware mod is a pretty neat job already, the real strength of this project is in the software. [Jeff] worked hard to implement all relevant features and mimic the original interface as much as possible, even using 1G phone test equipment to simulate incoming calls from the long-gone network. He also added menu features to enable Bluetooth pairing, use voice assistants, and even play games including versions of Snake and Tetris stripped down to match the handset display’s constraints.

As classic phone conversions go, this is definitely one of the most impressive. [Jeff]’s extensive documentation should come in handy if you’ve got a similar model, but if you don’t, there’s still plenty of ways to connect modern electronics without defacing your classic ride’s interior.

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Coffee Grinder Gets Bluetooth Weighing

March 16, 2023 by 7 Comments

Some people take their coffee grinding seriously. So what do you do when the hot new grinders automatically weigh coffee, and yours doesn’t? Well, if you are like [Tech Dregs] and the rest of us, you hack your existing grinder, of course. The link is to the source code, but for a quick overview, check out the video below.

In true hacker fashion, the first order of business was to pull a load cell out of a cheap scale. Originally, he intended to reuse the processor inside, too, but it was epoxied, so it was a good excuse to use some more modules. A load cell amplifier, an OLED display, and a tiny Xiao processor, which he describes as “ridiculous.” From the context, we think he means ridiculously small in the physical sense and ridiculously powerful for such a tiny board.

With the modules, the wiring wasn’t too hard, but you still need some kind of app. Thanks to App Inventor, an Android app was a matter of gluing some blocks together in a GUI. Of course, the devil is in the details, and it took a lot of “focused cursing” to get everything working correctly.

The coffee grinder has a relay to turn the motor on and off, so that’s the point the scale needs to turn the motor on and off. Conveniently, the grinder’s PCB had an unpopulated pin header for just this purpose.

This is one of those simple projects you can use daily if you drink coffee. We are always impressed that the infrastructure exists today and that you can throw something like this together in very little time without much trouble.

WiFi hacking coffee makers is a popular Java project in these parts. Upgrading a machine can get pretty serious with PID control loops and more.

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A MiniDisc Walkman, a MiniDisc and a pair of BlueTooth earphones

Wireless MiniDisc Walkman Has Bluetooth Inside

January 29, 2023 by 17 Comments

For most people, MiniDisc is just one of countless media formats that became obsolete when music went online. Not so for MiniDisc enthusiasts, many of whom still use a MiniDisc deck at home and a MiniDisc Walkman on the go. Unfortunately, high-end headphones these days often come with Bluetooth connectivity only, necessitating the use of clunky signal converters that ruin the tidy compactness of those portable players. [Daniel Rojas] cleverly solved this problem by directly adding Bluetooth functionality to a Sony MZ-R500 MiniDisc Walkman.

MiniDisc Walkmen are famously compact devices, so adding a full circuit board to one wasn’t easy. [Daniel] managed to squeeze the PCB from a Schosche wireless audio transmitter inside the front of the Walkman, next to the control buttons. He connected the audio signal to the transmitter’s input and rewired the little-used “End Search” button to become the “Pair” button. Sadly, the recording head and some associated hardware had to be removed in order to make space for the new component, turning the Walkman into a playback-only device.

A MiniDisc Walkman, opened up and showing a BlueTooth module inside
Lots of flying wires and Kapton tape, but it all fits.

The project’s GitHub page contains a detailed walk-through of the modification process that should enable anyone to reproduce the end result. [Daniel] didn’t arrive at the optimal solution in one go however, and he describes the three major revisions of his project in separate sections. In the first iteration for example, the Bluetooth module caused interference on the audio signal, which [Daniel] solved by adding isolation transformers in version two. He also includes a page full of technical information he collected during his project, which will come in handy if you ever want to perform other modifications on your MiniDisc Walkman.

We’ve seen several impressive projects where Bluetooth interfaces were added to pre-Bluetooth gadgets, ranging from tube radios to 8-track players. Some, like the iPod Nano, are even more space-constrained than a MiniDisc Walkman. Continue reading “Wireless MiniDisc Walkman Has Bluetooth Inside” →

Stadia Says Goodbye With Bluetooth And Crap Game

January 15, 2023 by 26 Comments

In just a few days time, Google’s Stadia game streaming service will finally shut down for good. But not for any technical reason, mind you. Microsoft has managed to demonstrate that streaming modern games over home and even mobile Internet connections is viable with their immensely popular Game Pass Ultimate service, and NVIDIA is making similar inroads with GeForce Now. No, like so many of Google’s failed experiments, they’ve simply decided they don’t want to play anymore and are taking their proverbial ball home back with them.

But not all is lost for those who shelled out money for Stadia’s wares. Not only will Google be refunding any money players spent on games, but a company representative has also announced they will be releasing a tool to unlock the latent Bluetooth capabilities of the service’s custom controller — hopefully stemming a surge of e-waste before it starts.

Thanks for playing, chumps.

In a forum thread titled “A Gift from the Stadia Team”, Community Manager [DanFromGoogle] explains that information on how you can enable Bluetooth on the controller will be coming next week. In the meantime, he also announced the immediate release of “Worm Game”, a tech demo that staffers apparently used to test out capabilities of the streaming service before its public release.

That this ridiculously simple game, which looks all the world like something a kid would crank out during an after-school programming class, will be the final title to officially release on Stadia is a stunningly insulting epitaph for the fledgling service. But then, Google seems to have developed a special affinity for mistreating their most loyal cattle users over these last few years.

Enabling Bluetooth on a game controller might not seem like such a big deal, but in this case, it will potentially give the piece of hardware a second chance at life. The Stadia controller is unique in that it uses WiFi to communicate directly over the Internet to Google’s streaming service, so once those servers stop responding, the orphaned device will end up being little more than a curiosity. Although it does technically work over USB, being able to use it wirelessly will not only provide a more modern experience, but help justify its internal batteries.

The last time we mentioned the Stadia controller, it was to document one user’s attempt to rid it of an internal microphone they didn’t feel comfortable with. Now that the service is being put to pasture, we wonder if we’ll start to see more hacks involving the admittedly interesting peripheral. We’ll certainly be keeping an eye out for them, but if you see anything we miss, you know where to send it.

A toy gamepad controlling Super Mario World emulated on a MacBook

Turning A Toy Gamepad Into A Real One, With Bluetooth

December 9, 2022 by 3 Comments

It’s important to instill healthy habits in your children when they’re still young. Preferences for sports, snacks and dinosaurs are typically formed in early childhood, as is loyalty to a specific gaming platform. [RetrogradeScene] apparently wished to steer his young daughter towards the Nintendo camp, but wasn’t looking forward to having her grubby hands touch his prized controllers. So he built her her own kid-friendly controller out of a Fisher-Price toy.

The toy in question is an imitation game controller that just makes funny sounds when you press the buttons. Converting it into a real, working game controller was a matter of soldering some wires onto the existing PCB and hooking them up to a microcontroller board, in this case a DFRobot FireBeetle. After loading the ESP32-BLE-Gamepad library and assigning the correct pin-button combinations in software [RetrogradeScene] ended up with a big, brightly-coloured gamepad that actually functioned as one.

Unfortunately, the FireBeetle took up space where the original AAA batteries were sitting, so the hacked gamepad needed a new power source. Classic batteries are heavy and inconvenient anyway, so [RetrogradeScene] installed a modern lithium battery plus a USB-C port for charging. Of course, no Bluetooth gadget is complete without an accompanying smartphone app either: [RetrogradeScene] wrote one for his iPhone that enables him to quickly change the button layout between the Nintendo and Xbox styles.

This might be a rare example of someone making a gamepad from, well, a gamepad. We’ve seen a few more unusual things being converted into game controllers, ranging from a handful of LEGO bricks to entire cars.

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A schematic explaining the workings of the Commodore 64's joystick port

Bluetooth Interface Adds Rumble Feedback To Commodore 64 Games

October 8, 2022 by 6 Comments

Nothing says “1980s gaming” like a black joystick with a single red fire button. But if you prefer better ergonomics, you can connect modern gamepads to your retrocomputers thanks to a variety of modern-to-classic interface adapters. These typically support just the directional pad and one or two action buttons, leaving out modern features like motion control and haptic feedback.

That’s a bit of a shame, because we think it would be pretty cool to feel that shock in our hands whenever Pitfall Harry drowns in quicksand or Frogger gets hit by traffic. We’re therefore happy to report that [Ricardo Quesada] has decided to add rumble functionality to the Bluetooth-to-Joystick-port interface that he’s been working on. He demonstrates the feature on his Commodore 64 in the video embedded after the break.

Naturally, any software needs to be adapted to support haptic feedback, but a trickier problem turned out to be the hardware: joystick ports are input-only devices and therefore cannot send “enable rumble” signals to any connected gamepads. [Ricardo] found a clever way around this, using the analog inputs on the joystick port that were typically used for paddle-type controllers.

The analog-to-digital converter inside the computer works by applying a pulse signal to the analog port and measuring the time it takes to discharge a capacitor. The modern gamepad interface simply detects whether these pulses are present; they can be enabled or disabled through software by toggling the analog readout on the joystick port. This way, the joystick port can be used to send a single bit of information to any device connected to it.

[Ricardo] developed patches for Rambo: First Blood part II and Leman to enable rumble functionality. He describes the process in detail in his blog post, which should enable anyone who knows their way around 6502 machine code to add rumble support to their favorite games.

The adapter works with a variety of retro systems that use the Atari-style joystick interface, but if you’re an Apple II user, you might want to look at this Raspberry Pi-based project that interfaces with its nonstandard joystick interface. If you’re into wireless gaming in general, be sure to also check out our history of wireless game controllers.

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ESP32 Adds Bluetooth To An IPod Nano

September 14, 2022 by 4 Comments

The iPod Nano was one of Apple’s masterworks, but it’s really tied down by its dependence on wired headphones. At least, that’s what [Tucker Osman] must have thought, as he spent an unreasonable amount of time designing a Bluetooth mod for the 3rd gen Nano. And it’s a thing of beauty — temperamental, brutally difficult to build, and fragile in use, but still beautiful. And while some purists try to keep their signal analog, [Tucker]’s coup d’etat is to intercept the iPod’s audio signal before the DAC chip, keeping the entire signal path digital to the Bluetooth speaker. Oh, and he also managed to make the volume and track skip buttons work, back across the wireless void.

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