Section 21 Power-Down Modes
Rev. 2.00 Mar 09, 2006 page 808 of 906
REJ09B0292-0200
Oscillator
CKIO
(output)
NMI
NMIE
SBY
Oscillation
settling time
Standby mode
Start of
oscillation
WDT
set time
NMI exception
handling
Exception
service routine,
SBY = 1,
SLEEP instruction
NMI
exception
handling
Figure 21.1 Standby Mode Cancellation by NMI Interrupt
21.4.4
Clock Pause Function
When the clock is input from the CKIO pin, the clock frequency can be modified or the clock
stopped. The
CKPREQ
/CKM pin is provided for this purpose. Note that clock pauses are not
accepted while the watchdog timer (WDT) is operating (i.e. when the timer enable bit (TME) in
the WDT’s timer control/status register (WTCSR) is 1). When the clock pause request function is
used, the standby bit (SBY) in the standby control register 1 (SBYCR1) must be set to 1 before
inputting the request signal. The clock pause function is used as described below.
1. Set the TME bit in the watchdog timer’s WTCSR register to 0, and set the SBY bit in
SBYCR1 to 1.
2. Apply a low level to the
CKPREQ
/CKM pin.
3. When the chip enters the standby state internally, a low level is output from the
CKPACK
pin.
4. After confirming that the
CKPACK
pin has gone low, perform clock halting or frequency
modification.
5. To cancel the clock pause state (standby state), apply a high level to the
CKPREQ
/CKM pin.
(Inside the chip , the standby state is canceled by detecting a rising edge at the
CKPREQ
/CKM
pin.)
Summary of Contents for SH7616
Page 10: ...Rev 2 00 Mar 09 2006 page x of xxvi ...
Page 132: ...Section 2 CPU Rev 2 00 Mar 09 2006 page 106 of 906 REJ09B0292 0200 ...
Page 568: ...Section 12 16 Bit Free Running Timer FRT Rev 2 00 Mar 09 2006 page 542 of 906 REJ09B0292 0200 ...
Page 582: ...Section 13 Watchdog Timer WDT Rev 2 00 Mar 09 2006 page 556 of 906 REJ09B0292 0200 ...
Page 706: ...Section 16 Serial I O SIO Rev 2 00 Mar 09 2006 page 680 of 906 REJ09B0292 0200 ...
Page 820: ...Section 19 Pin Function Controller PFC Rev 2 00 Mar 09 2006 page 794 of 906 REJ09B0292 0200 ...
Page 932: ...Appendix D Package Dimensions Rev 2 00 Mar 09 2006 page 906 of 906 REJ09B0292 0200 ...
Page 935: ...SH7616 Hardware Manual ...