LCD plug and interrupt

Added by physikus almost 7 years ago


on the LCD plug the interrupt pin from the port is connected to the interrupt pin of the MCP23008, which is an output pin.

I do not really understand why this is done and if there is any functionality due to this fact. I haven’t found information about this in the documentation of the LCD plug. In my project, I would like to use the interrupt pin (of the JN ports) for a kind of wake-up button. Thus, I am concerned if there might by some interference with some signal provided by the LCD plug.

Could anyone explain the meaning of this connection to me?



Replies (1)

RE: LCD plug and interrupt - Added by martynj almost 7 years ago


The LCD plug PCB has a position marked for a 2pin connector (JP1) that connects to GND and P5 on the MCP20038. This is intended to generate an interrupt when the 2pins are shorted by a suitable push button switch.

Ergo, no connector installed, no collision with using the IRQ line for some other requirement.