Computer Hardware User's Manual

100
CHAPTER 5 EXPLANATION OF INSTRUCTIONS
User's Manual U12326EJ4V0UM
Return from Break
RETB
Return from Software Vectored Interrupt
[Instruction format] RETB
[Operation] PC
L ← (SP),
PC
H ← (SP+1),
PSW ← (SP+2),
SP ← SP+3
[Operand]
None
[Flag]
ZACCY
RRR
[Description]
• This is a return instruction from the software interrupt generated with the BRK instruction.
• The data saved in the stack returns to the PC and the PSW, and the program returns from the interrupt service
routine.
• None of interrupts are acknowledged between this instruction and the next instruction to be executed.