Review on Waveshare POE HAT (C) For Raspberry Pi 4B/3B+ by Andrew Sticher

It's really big compared to other screens (35mm overall height with Pi 4B) so it's impossible to make a ready made case for the whole Pi+ Hut to find Setup. I ended up printing it myself. The fan is very noisy and the cable was pinched when I unpacked it, but it works. I left it with the switch in the "always on" position because otherwise the overheating SOC would have to save itself. The build quality is good. Tantalum capacitors might not last forever, but that's fine for my purposes. In addition, with fan and OLED, there is nothing comparable. The documentation for accessing fans and OLED I/O is not very detailed. If they just provided a diagram showing the addresses of the I2C OLED and I/O expander that the fan drives, that would be much more useful than the C program they provided instead. Also, it would make more sense for the I/O expander to be a device tree overlay so the fan shows up as GPIO in the debug files. Instead, the C sample program writes a byte sequence to turn the fan on and off. Not very clean.