NeoCal for Pocket PC User Guide
Selecting the Programmer group of functions places the calculator into integer mode, with the type of integer specified in the Preferences dialog. The , , , , and buttons operate on the integer part of their operands and return an integer for their result. The button also works differently in integer mode by converting x to the type of integer specified in the Preferences dialog.
Switching away from the Programmer function group restores these functions to work with real numbers and returns the display to decimal mode. These buttons are marked with a dot in the upper right corner as a reminder that they function differently in integer mode.
Integer mode can also be set for the User function group by checking the Integer option in the Keyboard dialog.