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Chapter 17
Interrupt/Exception Processing Function
User’s Manual U16702EE3V2UD00
Figure 17-28:
Exception Trap Processing
(2)
Restore
Recovery from an exception trap is carried out by the DBRET instruction. By executing the DBRET
instruction, the CPU carries out the following processing and controls the address of the restored
PC.
<1> Loads the restored PC and PSW from DBPC and DBPSW.
<2> Transfers control to the address indicated by the restored PC and PSW.
Figure 17-29 illustrates the restore processing from an exception trap.
Figure 17-29:
Restore Processing from Exception Trap
Exception trap (ILGOP) occurs
DBPC
DBPSW
PSW.NP
PSW.EP
PSW.ID
PC
Restored PC
PSW
1
1
1
00000060H
Exception processing
CPU processing
DBRET instruction
PC
PSW
DBPC
DBPSW
Jump to address of restored PC
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