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Section 6 Power-Down Modes
Rev. 4.00 Sep. 14, 2005 Page 173 of 982
REJ09B0023-0400
2. Canceling Standby Mode
Standby mode is canceled by interrupts (
NMI
,
IRQ
) or a reset.
•
Canceling with an Interrupt
The on-chip WDT can be used for hot starts. When an interrupt request is detected at the rising
or falling edge of
NMI
or
IRQ
, the clock will be supplied to the entire chip and standby mode
canceled after the time set in the WDT's timer control/status register has elapsed. The
STATUS1 and STATUS0 pins go low. Interrupt handling then begins and a code indicating
the interrupt source is set in the INTEVT2 registers. After the branch to the interrupt handling
routine, clear the STBY bit in the STBCR register. WDT stops automatically. If the STBY bit
is not cleared, WDT continues operation and a transition is made to standby mode* when the
WTCNT reaches H'80. A manual reset will not be accepted while the STBY bit is set.
Interrupts are accepted in standby mode even when the BL bit in the SR register is 1. If
necessary, save SPC and SSR to the stack before executing the SLEEP instruction.
Immediately after an interrupt is detected and until the system is taken out of standby mode,
the phase of the clock outputs from the CKIO and CKIO2 pins may be unstable.
Notes: * This standby mode can be canceled only by a power-on reset.
WTCNT value
H'FF
H'80
Time
Interrupt
request
WDT overflow and branch to
interrupt handling routine
Crystal oscillator settling
time and PLL synchronization
time
Clear bit STBCR.STBY before
WTCNT reaches H'80. When
STBCR. STBY is cleared, WTCNT
halts automatically.
Figure 6.1 Canceling Standby Mode with STBCR.STBY
•
Canceling with a Reset
Standby mode is canceled by a reset using the
RESETP
or
RESETM
pin. Keep the
RESETP
or
RESETM
pin low until the clock oscillation settles. The internal clock will continue to be
output to the CKIO pin.
Содержание HD6417641
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Страница 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
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Страница 204: ...Section 4 Clock Pulse Generator CPG Rev 4 00 Sep 14 2005 Page 154 of 982 REJ09B0023 0400...
Страница 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Страница 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Страница 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Страница 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Страница 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Страница 500: ...Section 13 Direct Memory Access Controller DMAC Rev 4 00 Sep 14 2005 Page 450 of 982 REJ09B0023 0400...
Страница 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Страница 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Страница 734: ...Section 18 Multi Function Timer Pulse Unit MTU Rev 4 00 Sep 14 2005 Page 684 of 982 REJ09B0023 0400...
Страница 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Страница 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Страница 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Страница 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Страница 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
Страница 1032: ...Rev 4 00 Sep 14 2005 Page 982 of 982 REJ09B0023 0400 X X Y data addressing 52 X Y memory 193...
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Страница 1036: ...SH7641 Hardware Manual...