Section 5 Interrupt Controller
Rev. 3.00 Jan 25, 2006 page 101 of 872
REJ09B0286-0300
5.7
Usage Notes
5.7.1
Conflict between Interrupt Generation and Disabling
When an interrupt enable bit is cleared to 0 to disable interrupt requests, the disabling becomes
effective after execution of the instruction. When an interrupt enable bit is cleared to 0 by an
instruction such as BCLR or MOV, and if an interrupt is generated during execution of the
instruction, the interrupt concerned will still be enabled on completion of the instruction, 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 rule is also applied when an interrupt source flag is cleared to 0. Figure 5.10
shows an example in which the CMIEA bit in the TMR's TCR register is cleared to 0.
The above conflict will not occur if an enable bit or interrupt source flag is cleared to 0 while the
interrupt is masked.
Internal
address bus
Internal
write signal
φ
CMIEA
CMFA
CMIA
interrupt signal
TCR write cycle
by CPU
CMIA exception handling
TCR address
Figure 5.10 Conflict between Interrupt Generation and Disabling
Содержание H8S/2158
Страница 10: ...Rev 3 00 Jan 25 2006 page viii of lii...
Страница 36: ...Rev 3 00 Jan 25 2006 page xxxiv of lii B Product Lineup 863 C Package Dimensions 864 Index 865...
Страница 47: ...Rev 3 00 Jan 25 2006 page xlv of lii Appendix Figure C 1 Package Dimensions TBP 112A 864...
Страница 54: ...Rev 3 00 Jan 25 2006 page lii of lii...
Страница 70: ...Section 1 Overview Rev 3 00 Jan 25 2006 page 16 of 872 REJ09B0286 0300...
Страница 118: ...Section 3 MCU Operating Modes Rev 3 00 Jan 25 2006 page 64 of 872 REJ09B0286 0300...
Страница 126: ...Section 4 Exception Handling Rev 3 00 Jan 25 2006 page 72 of 872 REJ09B0286 0300...
Страница 198: ...Section 6 Bus Controller Rev 3 00 Jan 25 2006 page 144 of 872 REJ09B0286 0300...
Страница 326: ...Section 10 8 Bit PWM Timer PWM Rev 3 00 Jan 25 2006 page 272 of 872 REJ09B0286 0300...
Страница 440: ...Section 15 Watchdog Timer WDT Rev 3 00 Jan 25 2006 page 386 of 872 REJ09B0286 0300...
Страница 606: ...Section 17 I 2 C Bus Interface IIC Rev 3 00 Jan 25 2006 page 552 of 872 REJ09B0286 0300...
Страница 742: ...Section 19 Multimedia Card Interface MCIF Rev 3 00 Jan 25 2006 page 688 of 872 REJ09B0286 0300...
Страница 744: ...Section 20 Encryption Operation Circuit DES and GF Rev 3 00 Jan 25 2006 page 690 of 872 REJ09B0286 0300...
Страница 750: ...Section 21 D A Converter Rev 3 00 Jan 25 2006 page 696 of 872 REJ09B0286 0300...
Страница 768: ...Section 22 A D Converter Rev 3 00 Jan 25 2006 page 714 of 872 REJ09B0286 0300...
Страница 770: ...Section 23 RAM Rev 3 00 Jan 25 2006 page 716 of 872 REJ09B0286 0300...
Страница 824: ...Section 26 Clock Pulse Generator Rev 3 00 Jan 25 2006 page 770 of 872 REJ09B0286 0300...
Страница 844: ...Section 27 Power Down Modes Rev 3 00 Jan 25 2006 page 790 of 872 REJ09B0286 0300...
Страница 878: ...Section 28 List of Registers Rev 3 00 Jan 25 2006 page 824 of 872 REJ09B0286 0300...
Страница 926: ...Index Rev 3 00 Jan 25 2006 page 872 of 872 REJ09B0286 0300...