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CHAPTER 12 INTERRUPT FUNCTIONS
User’s Manual U15104EJ2V0UD
12.4.5 Pending interrupt requests
Even if an interrupt request is generated, the following instructions hold it pending.
• MOV PSW, #byte
• MOV A, PSW
• MOV PSW, A
• MOV1 PSW.bit, CY
• MOV1/AND1/OR1/XOR1 CY, PSW.bit
• SET1/CLR1 PSW.bit
• RETB
• RETI
• PUSH PSW
• POP PSW
• BT/BF/BTCLR PSW.bit, $addr16
• EI
• DI
• Instructions manipulating IF0L, IF0H, MK0L, MK0H, PR0L, and PR0H registers
Caution
Because the IE flag is cleared to 0 by the software interrupt (caused by execution of the BRK
instruction), a maskable interrupt request is not acknowledged even if it occurs while the BRK
instruction is executed. However, a non-maskable interrupt is acknowledged.
Figure 12-14. Pending Interrupt Request
Remarks 1. Instruction N: Instruction that holds interrupt request pending
2. Instruction M: Instruction that does not hold interrupt request pending
3. Operation of
××
IF is not affected by value of
××
PR.
CPU processing
××
IF
Instruction N
Instruction M
Save PSW and PC,
jump to interrupt servicing
Interrupt servicing
program
Содержание mPD178053
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