Correct way to calculate PR, PD and IC

Hi

We have resistors on our PCB for DIO1-4 set as digital input (3). The PCB works great. A question can we remove the physical resistors and use PR and PD for the same purpose?

I am not calculating correct values for PR and IC apparently because the results are not what I expect. If I want a pull down resistor on DIO1,2,3,4 and DIO11 what is the value for PR and for IC change detect?

This came from the knowledge base. I cannot get 0x40 out of the binary value.
IC=0x40 (binary: 0010 1000) - …DIO3 and DIO5 for any change…

the above is from
http://knowledge.digi.com/articles/Knowledge_Base_Article/Digital-and-analog-sampling-using-XBee-radios

Thank you.

what radio and firmware are you working with?