An animated GIF of Engineer Bo's Precision Bluetooth Scroll Wheel wirelessly, and effortlessly scrolling down the Hack A Day blog with a single finger

Doomscroll Precisely, And Wirelessly

December 31, 2024 by Michael Shaub 18 Comments

Around here, we love it when someone identifies a need and creates their own solution. In this case, [Engineer Bo] was tired of endless and imprecise scrolling with a mouse wheel. No off-the-shelf solutions were found, and other DIY projects either just used hacked mice scroll wheels, customer electronics with low-res hardware encoders, or featured high-res encoders that were down-sampled to low-resolution. A custom build was clearly required.

We loved seeing hacks along the whole process by [Engineer Bo], working with components on hand, pairing sensors to microcontrollers to HID settings, 3D printing forms to test ergonomics, and finishing the prototype device. When 3D printing, [Engineer Bo] inserted a pause after support material to allow drawing a layer of permanent marker ink that acts as a release agent that can later be cleaned with rubbing alcohol.

We also liked the detail of a single hole inside used to install each of the three screws that secure the knob to the base. While a chisel and UV-curing resin cleaned up some larger issues with the print, more finishing was required. For a project within a project, [Engineer Bo] then threw together a mini lathe with 3D printed and RC parts to make sanding easy.

Scroll down with your clunky device to see the video that illustrates the precision with a graphic of a 0.09° rotation and is filled with hacky nuggets. See how the electronics were selected and the circuit designed and programmed, the use of PCBWay’s CNC machining in addition to board assembly services, and how to deal with bearings that spin too freely. [Engineer Bo] teases that a future version might use a larger bearing for less wobble and an anti-slip coating on the base. Will the board files and 3D models be released, too? Will these be sold as finished products or kits? Will those unused LED drivers be utilized in an upcoming version? We can’t wait to see what’s next for this project.

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When The EU Speaks, Everyone Charges The Same Way

December 30, 2024 by Jenny List 98 Comments

The moment everyone has been talking about for years has finally arrived, the European Union’s mandating of USB charging on all portable electronic devices is now in force. While it does not extend beyond Europe, it means that there is a de facto abandonment of proprietary chargers in other territories too. It applies to all mobile phones, tablets, digital cameras, headphones, headsets, game consoles, portable speakers, e-readers, keyboards, mice, portable navigation systems and earbuds, and from early 2026 it will be extended to laptops.

Hackaday readers will probably not need persuading as to the benefits of a unified charger, and truth be told, there will be very few devices that haven’t made the change already. But perhaps there’s something more interesting at work here, for this moment seals the place of USB-C as a DC power connector rather than as a data connector that can also deliver power.

Back in 2016 we lamented the parlous state of low voltage DC power standards, and in the time since then we’ve arrived at a standard involving ubiquitous and commoditised power supplies, cables, and modules which we can use for almost any reasonable power requirement. You can thank the EU for that mobile phone now having the same socket as its competitor, but you can thank the USB Implementers Forum for making DC power much simpler.

An LCD, Touch Sensor, USB-C, And A Microcontroller For A Buck

December 21, 2024 by Lewin Day 16 Comments

[CNLohr] has been tinkering with some fun parts of late. He’d found out that ordinary LCD screens could be used as simple touch sensors, and he had to try it for himself. He ended up building a little doohickey that combined USB C, an LCD display, and a touch interface, all for under a buck. You can check out the video below.

The key to this build was the CH32V003 CPU. It’s a RISC-V microcontroller that runs at a healthy 48 MHz, and it costs just 10 cents in reasonable quantities. A PCB etched to mate with a USB C cable eliminates the need for a connector.

[CNLohr] then gave the board a three-digit 7-segment LCD display from Aliexpress, which can be had for around 21 cents if you buy 100 or more. He then figured out how to drive the LCDs with a nifty trick that let the microcontroller use the display as a crude touch sensor. All in all, the total bill of materials for one of these things comes out somewhere under a dollar in quantity.

It’s mostly a random assemblage of tech glued together for a demo, but it’s a fun project. It’s worth checking out even if it’s just to learn how to create an integral USB C port on your own PCBs. The way it’s achieved with the etched contacts and milled-out tabs is pure elegance. Files are on Github for the curious.

We’ve featured a ton of [CNLohr’s] work over the years; the clear keytar was a glowing highlight, as were his early discoveries in the depths of the ESP8266.

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USB-C For Hackers: Reusing Cables

November 21, 2024 by Arya Voronova 83 Comments

Your project needs a cable, and since USB-C cables are omnipresent now, it’s only natural to want to reuse them for your evil schemes. Ever seen USB 3.0 cables used for PCIe link carrying duty? It’s because USB 3.0 cables are built to a reasonably high standard, both sockets and cables are easy to find, and they’re cheap. Well, USB-C cables beat USB 3.0 cables by all possible metrics.

Let’s go through USB-C cable reuse in great detail, and see just what exactly you get when you buy either a gas station C-C USB 2.0 cable, or, the fanciest all-features-supported 240 W Thunderbolt cable that money can buy. Looking for a cable to cut, or something to pass a seriously high-speed link? You’re reading the right article.

The Omnipresent Cables

USB-A to USB-C cables are the least interesting. They’re equivalent to a microUSB to USB-A cable, except there’s a resistor on the USB-C plug, connected from VBUS to one of the CC pins. That’s it. The cable contains four conductors, there’s really not much new. Save these cables for all the devices still built without the 5.1 kΩ resistors.

Now, a USB-C to USB-C cable – let’s say, 60 W max, the default USB-C cable capability. If your cable says anything less than 60 W, say, “2 A” or “15 W”, that’s a lie – it can handle 60 W no problem, all USB-C to C cables can do 60 W. This cable is also cool – for one, it has five conductors; GND, VBUS, D+, D-, and CC. Two of them (GND and VBUS) are guaranteed to be thick enough to carry 3 A without much voltage drop if any, too!

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Power Supply With Benchtop Features Fits In Your Pocket

November 19, 2024 by Donald Papp 42 Comments

[CentyLab]’s PocketPD isn’t just adorably tiny — it also boasts some pretty useful features. It offers a lightweight way to get a precisely adjustable output of 0 to 20 V at up to 5 A with banana jack output, integrating a rotary encoder and OLED display for ease of use.

PocketPD leverages USB-C Power Delivery (PD), a technology with capabilities our own [Arya Voronova] has summarized nicely. In particular, PocketPD makes use of the Programmable Power Supply (PPS) functionality to precisely set and control voltage and current. Doing this does require a compatible USB-C charger or power bank, but that’s not too big of an ask these days.

Even if an attached charger doesn’t support PPS, PocketPD can still be useful. The device interrogates the attached charger on every bootup, and displays available options. By default PocketPD selects the first available 5 V output mode with chargers that don’t support PPS.

The latest hardware version is still in development and the GitHub repository has all the firmware, which is aimed at making it easy to modify or customize. Interested in some hardware? There’s a pre-launch crowdfunding campaign you can watch.

PicoROM, A DIP-32 8-Bit ROM Emulator

November 5, 2024 by Dave Rowntree 13 Comments

As we all know, when developing software for any platform or simply hacking a bit of code to probe how something works, the ability to deploy code rapidly is a huge help. [Martin Donlon], aka [wickerwaka], is well known in retro gaming and arcade hardware reverse engineering circles and had the usual issues figuring out how an arcade CPU board worked while developing a MiSTer core. Some interesting ASICs needed quite a bit of poking, and changing the contents of socketed ERPOMs is a labour-intensive process. The solution was PicoROM, a nicely designed ROM emulator in a handy DIP-32 form factor.

As the title suggests, PicoROM is based on the Raspberry Pi RP2040. It emulates an 8-bit ROM up to 2MBits in size with speeds up to 100ns. Since it uses the RP2040, USB connectivity is simple, enabling rapid uploading of new images to one (or more) PicoROMs in mere seconds. A vertically orientated USB-C connector allows multiple PicoROMs to be cabled to the host without interfering with neighbouring hardware. The firmware running on core 1 passes data from the internal 264K SRAM, using the PIO block as a bus interface to the target. A neat firmware feature is the addition of a mechanism to use a ROM region as a bidirectional control channel, which the software running on the target can use to communicate back to the host computer. This allows remote triggering of actions and the reporting of responses. Responses which may not be physically observable externally. [Martin] is using this feature extensively to help probe the functionality of some special function chips on the target boards, which is still a slow process but helped massively by reducing that critical software iteration time. The PCB was designed with KiCAD. The project files for which can be found here.

This isn’t the first time we’ve seen the RP2040 used for ROM emulation; here’s a pile of wires that does the same job. It just isn’t as pretty. Of course, if you really must use EPROMs, then you could give this sweet programmer a look over.

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Open-Source, 3D Printed Trackpad

October 21, 2024 by Bryan Cockfield 22 Comments

Touchpads, or trackpads, have been around since the 1980s. Today, you can often find them in laptops and notebook computers as pointing devices. With no moving parts, a trackpad are easy to integrate into the body of a portable computer. they’re much smaller than the traditional mouse. Until the advent of multitouch and gestures over the past two decades, though, they were generally poor substitutes for an actual mouse. These days, trackpads have enough features that some users prefer them even on their desktop computers. If you’re that type of person and don’t want to shell out a big pile of money for an Apple, Logitech, or other off-the-shelf trackpad you can always build your own.

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