[endes0] has been hacking with USB HID recently, and a Logitech M185 mouse’s USB receiver has fallen into their hands. Unlike many Logitech mice, this one doesn’t include a Unifying receiver, though it’s capable of pairing to one. Instead, it comes with a pre-paired CU0019 receiver that, it turns out, is based on a fairly obscure TC32 chipset by Telink, the kind we’ve seen in cheap smart wristbands. If you’re dealing with a similarly obscure MCU, how do you even proceed?

In this case, GitHub had a good few tools developed by other hackers earlier — a Ghidra integration, and a tool for working with the MCU using a USB-UART and a single resistor. Unfortunately, dumping memory through the MCU’s interface was unreliable and frustrating. So it was time to celebrate when fuzzing the HID endpoints uncovered a memory dump exploit, with the memory dumper code helpfully shared in the blog post.

From a memory dump, the exploration truly began — [endes0] uncovers a fair bit of dongle’s inner workings, including a guess on which project it was based on, and even a command putting the dongle into a debug mode where a TC32-compatible debugger puts this dongle fully under your control.

Yet another hands-on course on Ghidra, and a wonderful primer on mouse dongle hacking – after all, if you treat your mouse’s dongle as a development platform, you can easily do things like controlling a small quadcopter, or pair the dongle with a SNES gamepad, or build a nifty wearable.

How hard could it be to add an extra USB port inside your laptop? As [Joshua Stein] shows, it can be decently hard, but you will have fun along the way. His journey involves a Thinkpad X1 Nano, and his tech setup means it’d be most comfortable for him to have a USB port inside its case, for a Logitech mouse’s USB receiver. It wasn’t smooth sailing all throughout, but the end result is no doubt beautifully executed.

M.2 B-key, A-key and E-key slots have USB 2.0 available on them – you’d think that’s perfect for such a receiver, and there’s even plug and play adapters for this on places like eBay. Unfortunately, none of these, as Lenovo implements wireless card whitelists to this day. Tinkering with the whitelist on [Joshua]’s laptop resulted in BIOS digital signature check failures, and the USB-connected fingerprint reader was ultimately chosen as the most viable path.

Initially, he’s tested the fingerprint reader with an FPC breakout, having the USB connection work – many a hacker would stop here, pulling a few bodge wires from the breakout. [Joshua], however, raised the bar, creating a flexible PCB that would pull the fingerprint connector signals to a spot in the case where the USB receiver could fit neatly, with a 5 V step-up on the board, too.

[Joshua] tops it off by showing a 3D-printed spacer that goes into now-vacant spot where the fingerprint reader used to be. This mod is not open-source as far as we can see, but it’s definitely an inspiration. Want to put even more USB devices inside your laptop? Perhaps a tiny USB hub would help, in line with the EEE PC mods that aimed to stuff the tiny laptop with the largest amount of USB devices possible.

The Surface Arc is a designed-for-travel mouse that carries flat, but curves into shape for use. It even turns on when it’s bent and shuts itself off when it’s flat. The device isn’t particularly new, but [Mr Teardown] was a bit surprised at the lack of details about what’s inside so tears it down in a video to reveal just how the mechanism works.

The snap-action of the bending is accomplished with the help of a magnetic connection near the bottom end of the mouse’s “tail”, locking it into place when flexed. Interestingly, the on and off functionality does not involve magnets at all. Power control is accomplished by a little tab that physically actuates a microswitch.

There are a few interesting design bits that we weren’t expecting. For example, there is no mechanical scroll wheel. The mouse delivers similar functionality with touch sensors and a haptic feedback motor to simulate the feel and operation of a mechanical scroll wheel.

[Mr Teardown] finds the design elegant and effective, but we can’t help but notice it also seems perhaps not as optimized as it could be. There are over 70 components in all, including 23 screws (eight different kinds!), and it took [Mr Teardown] the better part of 45 minutes to re-assemble it. You can watch the entire teardown in the video embedded just under the page break; it’s a neat piece of hardware for sure.

If you’re in the mood for another mouse teardown, we have a treat for you: an ancient optical mouse from the 80s that required a special surface to work.

[via Core77]

For decades now, we’ve been able to quickly and reliably interface musical instruments to computers. These tools have generally made making and recording music much easier, but they’ve also opened up a number of other out-of-the-box ideas we might not otherwise see or even think about. For example, [Joren] recently built a human interface device that lets him control a computer’s cursor using a flute instead of the traditional mouse.

Rather than using a MIDI interface, [Joren] is using an RP2040 chip to listen to the flute, process the audio, and interpret that audio before finally sending relevant commands to control the computer’s mouse pointer. The chip is capable of acting as a mouse on its own, but it did have a problem performing floating point calculations to the audio. This was solved by converting these calculations into much faster fixed point calculations instead. With a processing improvement of around five orders of magnitude, this change allows the small microcontroller to perform all of the audio processing.

[Joren] also built a Chrome browser extension that lets a flute player move a virtual cursor of sorts (not the computer’s actual cursor) from within the browser, allowing those without physical hardware to try out their flute-to-mouse skills. If you prefer your human interface device to be larger, louder, and more trombone-shaped we also have a trombone-based HID for those who play the game Trombone Champ.