This module can be purchased on Xinabox CC.
This ☒CHIP forms part of the output modules and is equipped with a high speed IO expander chip. The OC04 module is able to switch loads been 85~265 VAC/VDC at a maximum load current of 8A. The OC04 provides an additional terminal for users to connect and external push button for relay control.
The OC04 ☒CHIP is housed in an compact 2U×4U chip with three connection ports.
More information on the PCA9554A can be found in the datasheet.
To install the libraries please followed the guide provided on the Arduino Website under "Importing a .zip Library".