📦 NOYITO PCF8574 IO Expansion Board I2C Bus Development Module (Pack of 2) - Enhance I/O Capability Effortlessly Review

The NOYITO Expansion Expander is a great edition for single board computers. Based on our own experience, we can say that this board is easy to set up and provides multiple options for expansion, including GPIO headers and I2C interfaces. The build quality is also excellent, with a sturdy aluminum casing. The only downside we found is that the board may get a bit warm, but it's not a big issue. Overall, we highly recommend this expansion board for anyone looking to expand their single board…

I use it to connect some old ICs to my microcontroller via an 8-bit parallel bus. No questions. Outstanding quality for the money.

The definition says it's quasi-bidirectional - a strange term - but if you look at the PIN diagram it all becomes clear. While they're great for OUTPUT (assuming a 1mA source or 25mA sink is sufficient), as an INPUT they fall badly in my opinion. The input must be able to overcome the 1mA OUTPUT enough to reduce the signal level. And your code MUST write HIGH to the INPUT pin before attempting to read. In short, I consider them for OUTPUT use ONLY. They work as an input, but IMO puts a load on…