The project was detailed on 314 Reactor, a blog dedicated to specialist electronics projects with questionable practicality. The device’s creator set out with the intention of running Windows 98 on the Raspberry Pi and making it wrist-wearable.
Since the Pi’s specs are in excess of many Windows 98 PCs, there were no immediate issues with its hardware. The Raspberry Pi A+ used for the watch is a special low-cost variant of the original Pi, ideal for powering wearable devices. It draws minimal power and has only one USB connector.
The most problematic part of the project was getting Windows 98 to run on the Pi. Rather than boot the operating system directly, the QEMU emulation software is used to load Windows from within the Pi’s native Linux environment. QEMU is capable of replicating many full computer systems, including a range of processor architectures and peripheral devices.
Because QEMU is only an emulator, the Windows 98 watch’s performance isn’t exemplary. According to its inventor, the software is “usable” but “super slow.” Loading times are a particular issue as Windows 98 is loaded from the Pi’s SD card and configured in the emulator. Performance on the classic Windows 95 screensaver is “about 0.5fps,” the watch’s creator, known as Lord_of_Bone, told Gizmodo.
A TFT touchscreen connected to the Pi is used for interacting with the watch. There’s also a physical on/off button, a battery, set of buttons for loading Windows and a basic casing. With a few basic electronics skills, it’d be easy to replicate the watch using another Raspberry Pi.
Lord_of_Bone has plans to take the device further, extending the prototype to include a selection of other archaic operating systems. He plans to use push buttons along the edge of the watch to load different versions of Windows, including 95, ME and XP. Getting the classic game Doom to run on an emulated copy of Windows is also a target, although performance is currently at an excruciating 0.1fps.
In an attempt to increase the frame rate a little, Lord_of_Bone is intending to replace the Model A+ Raspberry Pi with a newer Pi 3. It’s faster and more powerful, although the improved processor will have little impact on QEMU’s emulation.
This week, the Raspberry Pi Foundation announced the new Pi Zero W, a tiny $10 version of the Pi that would be at home powering DIY smartwatches. It has slower hardware than the larger Pi 3 though.
The Windows 98 watch isn’t the most elegant of smartwatches. It’s also far from the first smartwatch to run a strange operating system, joining Android Wear watches that boot various Windows versions ranging from 95 through to XP. As with the Pi project, the QEMU emulator is generally used to hack strange operating systems onto modern devices.
