logitech k750 wireless solar powered keyboard

To achieve that, you need a virtual machine emulator that can do USB pass-through. I did not need it, but I learned a few things.Īnyway, my plan was the following: run the Logitech application inside a virtual machine running Windows, give it direct access to the USB keyboard, and sniff what happens on the USB wire. You might want to take a look at it if you want to reverse engineer on USB.

I discovered a bit too late that Drew Fisher did a good presentation on USB reverse engineering at 28c3. So the first task to accomplish is, unfortunately, to reverse engineer the program. Let's reverse engineer thisĪs far as I know, there's nothing in the USB HID protocol that handles this kind of functionality (battery status, light meter…) in a standard way. Pushing this same button while the application is running will makes the light meter activated: the application will tell you how much lux your keyboard is receiving. When pressed, a LED will light up on the keyboard: green if the keyboard is receiving enough light and is charging, red if the keyboard does not receive enough light and is therefore discharging. On the keyboard, there's a special 'light' button (up right). The Logitech application under Windows works that way: you launch it, and it displays the battery charge level. With this driver, each device attached to the receiver is recognized as one different device. Recently, a driver called hid-logitech-dj has been added to the Linux kernel. On old Linux kernel, the Unifying receiver is recognized as only one keyboard and/or one mouse device. It's an USB receiver that can be attached up to 6 differents devices (mouse, keyboards…). This keyboard, like many of the new wireless devices from Logitech, uses the Unifying interface. Someone should write code to get the battery status and light meter from Linux: challenge accepted! How the keyboard works This activity being quite energy consuming, it emptied the whole battery. My problem is that there's obviously no way to know the battery status from Linux, the provided application only working on Windows.Īnd one dark night, while fragging on QuakeLive, my keyboard stopped working: it had no battery left. It has an incredible useful feature: while being wireless, it has no need for disposable or rechargeable batteries, it uses solar power! I'm particularly picky on keyboards, but this one is good. A year ago, I bought a Logitech Wireless Solar Keyboard K750.

Logitech k750 wireless solar powered keyboard