This is an PCA9555 board for expanding the virtual pins on a DCC-EX command station via an I2C connection.
The I2C can either be by Qwiic cables or Dupont cables.
It has provision for connection of an interrupt back to the command station.
There is provision for external power to the sensors.
The power connector, output and address headers are included but not solder in place.
It does not include headers for the Dupont cables.
Includes one 50mm Qwiic cable.
There is an error on these pcbs that prevent them from being daisy chained to gether.
The board still works correctly as a GPIO expander but you can only access the board via I2C connected to the left hand Qwiic socket and headers in the image.
Multiple boards can be connected using either an I2C splitter or I2C mux.
These boards are tested as working other than the connection to the header and Qwiic connector at the righthand end of the board.
I2C splitters are available here:
I2C Splitter
This product was added to our catalog on Tuesday 04 February, 2025.