A Raspberry Pi Zero fits neatly onto the rear, although you’ll need to be careful when mounting it not to crack the screen – it’s best to put it face down on a soft surface. Short standoffs (not supplied) can be use to secure it. If using a full-size Raspberry Pi, you’ll need a GPIO booster header.
While the HyperPixel 2.1 Round uses all the GPIO pins, five breakout pins on the rear provide the option of connecting sensors via an alternate I2C interface.
HyperPixel 2.1 round display drivers
After installing drivers with terminal commands, rebooting sees Raspberry Pi desktop appear on the tiny display. Since the corners are missing, it’s nigh on impossible to navigate, so you’ll want to enable SSH access to issue further commands.
The Python touch library is installed separately and contains a few code examples, including a clock and a colour wheel. Pygame is used for these, but since it doesn't support the non-standard 480×480 resolution, you have to alter Raspberry Pi’s config.txt file to make it work – and add an extra part to the command when running code.
At the first attempt, the code examples appeared glitchy on screen – an update of Pygame rectified this, however.
Videos run really smoothly at 60fps, although the aspect ratio is squished horizontally to fit the screen.
Verdict
8/10
If you really want a round display, maybe for a Halloween animated eyeball, this is an excellent option.
Note: This article was updated on 3 September 2021 with information relating to the software driver.