diagnostic software

i am devoloping diagnostic firmware for the testing the hardware modules...

one test is of I/O Expander...its written:

I/O Expander:
· Enable the port as output and check voltage at test point TP10 .
· Enable the port as input, apply voltage and check for valid data.
· Probe on test points TP10, TP11, TP12,TP13 GPIO pins of I/O Expander.
· I2C address:0100000
·
I/O Expander test

Address / GPIO
Remarks
U5
0100000

TP10,TP11,TP12,TP13
GPIO values



i am using PIC24f microcontroller
can u explain me what does it mean??
i couldnt get the meaning....

i am attaching one file of the supervisory board which i have to test

Thanks
Puneet Gupta