@Dinesh A: The user output mode is easiest to set up by using the weak pull-down mode. So by default, user outputs will have a slow fall time. A slow rise time is indicative of an incorrect configuration---the weak pull-up and pull-down modes differ by a bit-shift, so it's fairly easy to get it into that state. For users who need to run faster than the weak-pull modes will allow, there are usually ways to tweak the configuration to get some of the output channels to run full-swing.