UPD784907 Datasheet, PDF (53/98 Pages) NEC – 16-BIT SINGLE-CHIP MICROCONTROLLER

µPD784907, 784908
9. INTERRUPT FUNCTION
The three types of interrupt request-response servicing, as shown in Table 9-1 below, can be selected by program.
Table 9-1. Servicing of Interrupt Request
Servicing Mode Servicing Agent
Servicing
PC and PSW Contents
Vectored interrupt Software
Branches and executes a servicing routine
(servicing is arbitrary).
Saves to and restores from the stack.
Context switching
Automatically switches register banks, and
branches and executes a servicing routine
(servicing is arbitrary).
Saves to or restores from fixed area in
the register bank.
Macro service
Firmware
Executes data transfer between memory and Maintained
I/O (servicing is fixed).
9.1 Interrupt Source
Table 9-2 shows the interrupt sources available. As shown, interrupts are generated by 27 types of sources,
execution of the BRK and BRKCS instructions, or an operand error.
Four levels of interrupt servicing priority can be set. Priority levels can be set to nest control during interrupt servicing
or to simultaneously generate interrupt requests. However, nested macro services are performed without suspension.
When interrupt requests having the same priority level are generated, they are serviced according to the default
priority (fixed) (see Table 9-2).
Data Sheet U11680EJ2V0DS00
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