UPD784938 Datasheet, PDF (563/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 23 INTERRUPT FUNCTIONS
23.8.3 Basic macro service operation
Interrupt requests for which the macro service processing generated by the algorithm shown in Figure 23-10 can be
specified are basically serviced in the sequence shown in Figure 23-17.
Interrupt requests for which macro service processing can be specified are not affected by the status of the IE flag, but
are disabled by setting (to 1) an interrupt mask flag in the interrupt mask register (MK0). Macro service processing can
be executed in the interrupt disabled state and during execution of an interrupt service program.
Figure 23-17. Macro Service Processing Sequence
Generation of interrupt request for which
macro service processing can be specified
Macro service processing execution ^{; Data transfer, real-time output port control}
MSC ← MSC-1
; Decrement macro service counter (MSC)
MSC = 0?
No
Yes
Interrupt service mode bit ← 0
No
VCIE = 1?
Yes
Interrupt request flag ← 0
Interrupt request generation
Execute next instruction
The macro service type and transfer direction are determined by the value set in the macro service control word mode
register. Transfer processing is then performed using the macro service channel specified by the channel pointer according
to the macro service type.
The macro service channel is memory which contains the macro service counter which records the number of transfers,
the transfer destination and transfer source pointers, and data buffers, and can be located at any address in the range FE00H
to FEFFH when the LOCATION 0 instruction is executed, or FFE00H to FFEFFH when the LOCATION 0FH instruction is
executed.
Preliminary User’s Manual U13987EJ1V0UM00
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