User Guide

Testing the Bitwise Compare Routine 229
Adding a Post Command to Each Title
To add a Post command for each title that returns play to the title menu:
1 In the Scenario Editor authoring area, drag from the Post flag for Title_1 to the title menu
PGC.
2 When prompted to specify the type of command link you want to add, select Add to the
end of the post command list” and click OK.
3 Repeat the previous steps for Title_2 and Title_3. The Bitwise Compare routine is
complete and ready to test.
Testing the Bitwise Compare Routine
With three buttons, there are four possible button selection combinations the viewer can
make. Selecting Button 3 only, or selecting either Button 1 or Button 2 and then Button 3,
will not cause both of the first two bits in GPRM0 to have a value of 1. Only when both bits
have a value of 1 will the Bitwise Compare return a True result, and only a True result allows
the viewer to view Title_3. The only combination that causes both of the first two bits in
GPRM0 to have a value of 1 is when the viewer selects Button 1 and Button 2, as shown in
Table 11.
Table 11: Truth table
Viewer selection GPRM0 Bit 1 Value GPRM0 Bit 0 Value Result
Button 3 only 0 0 False
Button 1 only 1 0 False
Button 2 only 0 1 False
Buttons 1 and Button 2 1 1 True