In a previous article, I published a small userspace image and Linux kernel for the Zenwatch 3 that enables root access with SSH over USB on the watch. By now, I reached my initial goal to get AsteroidOS, the alternative Android Wear operating system, running on the Zenwatch 3.

A few weeks ago, I started tinkering with my new Asus Zenwatch 3. As I wanted to make a backup first, I connected the watch with its USB cable to my PC. Before you can access the filesystem, you have to enable a developer mode first by tapping several times on the build number menu entry under "Settings" -> "Info". Then, you can control the watch using adb. Unfortunately, you do not get root privileges on the device, hence, you cannot backup all files.

To entertain the people in the waiting room of a dental surgery, the dentist bought a wall-mounted Full HD TV with integrated DVD player to show some pictures and videos. Unfortunately, the DVD player had no repeat function, so one of the assistants had to press play on the remote control a few times every day. As the dentist also wanted to change the pictures from time to time anyway - in order to show new offerings - I proposed to use a small embedded computer instead. As I was experimenting with some Raspberry Pis anyway, I started to build a system with such a device.

To debug a problem with my self-built kernel and initramfs, I took a look at the relevant kernel code. It is not a big surprise that understanding the process was not that easy. Hence, I made notes while digging through the code and wrote the following article afterwards with links to the great free-electrons website which greatly simplifies following the code online.

In the past, I used a mechanism based on scripts called by udev rules [1,2] to automatically add USB drives to VMs. On a new machine this fails now with the following message:

As all my devices with exchangeable storage use SD cards, every now and then I have to look for a new card. Unfortunately, even if you are only looking at the - in my opinion - two major vendors, Samsung and Sandisk, you have to choose between multiple series that even have a similar price.

To enable GRUB's serial terminal, there are various guides available. However, following these guides enables only the serial terminal and disables the normal interface with input from your keyboard and output on your display. This article shows how to enable both.