it simulates HMI user inputs. For example and OIP for that ran the following:
00010 OIP ("point.log","s/h/f/a/x/x/x/x/x")
on an apogee panel would add a Field Panel to the panel database that contained the PPCL program that holds the OIP command. (the x's represent new panel data) This would be triggered by a transition of the theoretical "point.log" Digital point to the ON position. This example is somewhat afunctional, due to the nature of the command being somewhat limited in terms of repeatability, but hopefully it will help you understand the OIP function.
The command sequences that are entered in the OIP command can be deciphered using the field panel user's manual.