Datasheet

Section 5 Interrupt Controller
Page 152 of 1434 R01UH0166EJ0600 Rev. 6.00
Mar 02, 2011
H8S/2633 Group, H8S/2633 F-ZTAT
TM
,
H8S/2633R F-ZTAT
TM
, H8S/2695
Table 5.10 Number of States in Interrupt Handling Routine Execution Statuses
Object of Access
External Device
8 Bit Bus 16 Bit Bus
Symbol
Internal
Memory
2-State
Access
3-State
Access
2-State
Access
3-State
Access
Instruction fetch S
I
1 4 6+2m 2 3+m
Branch address read S
J
Stack manipulation S
K
Legend:
m: Number of wait states in an external device access.
5.5 Usage Notes
5.5.1 Contention between Interrupt Generation and Disabling
When an interrupt enable bit is cleared to 0 to disable interrupts, the disabling becomes effective
after execution of the instruction.
In other words, when an interrupt enable bit is cleared to 0 by an instruction such as BCLR or
MOV, if an interrupt is generated during execution of the instruction, the interrupt concerned will
still be enabled on completion of the instruction, and so interrupt exception handling for that
interrupt will be executed on completion of the instruction. However, if there is an interrupt
request of higher priority than that interrupt, interrupt exception handling will be executed for the
higher-priority interrupt, and the lower-priority interrupt will be ignored.
The same also applies when an interrupt source flag is cleared to 0.
Figure 5.8 shows an example in which the CMIEA bit in the TMR’s TCR register is cleared to 0.