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Retb – NEC 78K/0 Series User Manual

Page 100

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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]

Z

AC

CY

R

R

R

[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.