UPD784938 Datasheet, PDF (565/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 23 INTERRUPT FUNCTIONS
(2) When VCIE bit is 1
In this mode, an interrupt is not generated after macro service ends. Figure 23-19 shows an example of macro service
and interrupt acknowledgment operations when the VCIE bit is 1.
This mode is used when the final operation is to be started by the last macro service processing performed, for instance.
It is mainly used in the following cases:
• Clocked serial interface receive data transfers (INTCSI/INTCSI1/INTCSI2)
• Asynchronous serial interface data transfers (INTST/INTST2)
• To stop a stepping motor in the case (INTC10/INTC11) of stepping motor control by means of macro service type
C using the real-time output port and timer/counter.
Figure 23-19. Operation at End of Macro Service when VCIE = 1
Main routine
EI
Macro service request
Macro service processing
Last macro service request
Processing of last macro service
Interrupt request due to the end of
the hardware operation started by
the last macro service processing
Interrupt servicing
Preliminary User’s Manual U13987EJ1V0UM00
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