[Soekris] Soekris NET4501 I/O Connector

[Eternity]

Hi!

I am running Linux on the NET4501. I want to be able to use the I/O 
Connector as input to get values from some external relays.

Are there any driver or code example on how to read status on the I/O
connector?

My hope was to be able to retrieve status from inside PHP code, to present 
it on a webpage.

Any help appreciated!

Regards,
Christian