UPD784938 Datasheet, PDF (596/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 23 INTERRUPT FUNCTIONS
23.10 Instructions whose Execution is Temporarily Suspended by an Interrupt or Macro Service
Execution of the following instructions is temporarily suspended by an acknowledgeable interrupt request or macro
service request, and the interrupt or macro service request is acknowledged. The suspended instruction is resumed after
completion of the interrupt service program or macro service processing.
Temporarily suspended instructions:
MOVM, XCHM, MOVBK, XCHBK
CMPME, CMPMNE, CMPMC, CMPMNC
CMPBKE, CMPBKNE, CMPBKC, CMPBKNC
SACW
23.11 Interrupt and Macro Service Operation Timing
Interrupt requests are generated by hardware. The generated interrupt request sets (to 1) an interrupt request flag.
When the interrupt request flag is set (to 1), a time of 8 clocks (0.64 µs: fCLK = 12.58 MHz) is taken to determine the
priority, etc.
Following this, if acknowledgment of that interrupt or macro service is enabled, interrupt request acknowledgment
processing is performed when the instruction being executed ends. If the instruction being executed is one which temporarily
defers interrupts and macro service, the interrupt request is acknowledged after the following instruction (see 23.9 When
Interrupt Requests and Macro Service are Temporarily Held Pending for deferred instructions).
Figure 23-42. Interrupt Request Generation and Acknowledgment (unit: clocks)
Interrupt request flag
8 clocks
Instruction
Interrupt request acknowledgment processing/macro service processing
596
Preliminary User’s Manual U13987EJ1V0UM00