Interrupt Acknowledge Time Of Cpu - NEC V850ES/SA2 UPD703201 Manual

14.6 Interrupt Acknowledge Time of CPU

Except the following cases, the interrupt acknowledge time of the CPU is 5 clocks minimum. To input interrupt
requests successively, input the next interrupt at least 5 clocks after the preceding interrupt.
• In software/hardware STOP mode
• When the external bus is accessed
• When interrupt request non-sampling instructions are successively executed (Refer to 14.7 Periods in Which
Interrupts Are Not Acknowledged.)
• When the interrupt control register is accessed
Figure 14-12. Pipeline Operation at Interrupt Request Acknowledgement (Outline)
Interrupt acknowledgement operation
Instruction (start instruction of
interrupt servicing routine)
Remark INT1 to INT4: Interrupt acknowledgement processing
IFX:
IDX:
Interrupt acknowledge time (internal system clock)
Internal interrupt
Minimum 4
Maximum 6
446
CHAPTER 14 INTERRUPT/EXCEPTION PROCESSING FUNCTION
Internal clock
Interrupt request
Instruction 1
Instruction 2
Invalid instruction fetch
Invalid instruction decode
External interrupt
4 +
Analog delay time
6 +
Analog delay time
Preliminary User's Manual U15905EJ1V0UD
4 system clocks
IF ID EX DF WB
IFX IDX
INT1 INT2 INT3 INT4
Condition
The following cases are exceptions.
• In IDLE/software STOP mode
• External bus access
• Two or more interrupt request non-sample instructions are
executed in succession
• Access to peripheral I/O register
IF IF ID EX