The PC routine definitions explained in this topic apply to both stacking and basic PC routines. For each PC routine you must define:

• Whether the PC routine will receive control in supervisor state or problem state
• Whether the PC routine is a space switch routine or a non-space switch routine
• The PSW key-mask (PKM) that a problem state program must have in order to invoke the PC routine
• The addressing mode of the PC routine if you specified the ROUTINE parameter on the ETDEF macro
• Whether the PC routine will run under the user's PSW-key mask or under a different PSW-key mask