199
Chapter 7
Interrupt/Exception Processing Function
Preliminary User’s Manual U14913EE1V0UM00
Figure 7-9: Example of Processing in Which Another Interrupt Request Is Issued While an Inter-
rupt Is Being Processed (1/2)
Caution: The values of the EIPC and EIPSW registers must be saved before executing multiple
interrupts. When returning from multiple interrupt servicing, restore the values of
EIPC and EIPSW after executing the DI instruction.
Remarks: 1. a to u in the figure are the temporary names of interrupt requests shown for the sake of
explanation.
2. The default priority in the figure indicates the relative priority between two interrupt
requests.
Main routine
EI
EI
Interrupt request a
(level 3)
Processing of a
Processing of b
Processing of c
Interrupt request c
(level 3)
Processing of d
Processing of e
EI
Interrupt request e
(level 2)
Processing of f
EI
Processing of g
Interrupt request g
(level 1)
Interrupt request h
(level 1)
Processing of h
Interrupt request b is acknowledged because the
priority of b is higher than that of a and interrupts are
enabled.
Although the priority of interrupt request d is higher
than that of c, d is held pending because interrupts
are disabled.
Interrupt request f is held pending even if interrupts are
enabled because its priority is lower than that of e.
Interrupt request h is held pending even if interrupts are
enabled because its priority is the same as that of g.
Interrupt
request b
(level 2)
Interrupt request d
(level 2)
Interrupt request f
(level 3)
Summary of Contents for V850E/CA1 ATOMIC
Page 6: ...6 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 52: ...52 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 144: ...144 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 162: ...162 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 224: ...224 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 308: ...308 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 512: ...512 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 564: ...564 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 566: ...566 Preliminary User s Manual U14913EE1V0UM00 MEMO ...
Page 584: ...584 Preliminary User s Manual U14913EE1V0UM00 MEMO ...