CHAPTER 19 STANDBY FUNCTION
User’s Manual U16899EJ2V0UD
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19.2.2 STOP mode
(1) STOP mode setting and operating statuses
The STOP mode is set by executing the STOP instruction, and it can be set when the CPU clock before the
setting was the high-speed system clock or Ring-OSC clock.
Caution Because the interrupt request signal is used to release the standby mode, if there is an
interrupt source with the interrupt request flag set and the interrupt mask flag reset, the
standby mode is immediately released if set. Thus, the STOP mode is reset to the HALT mode
immediately after execution of the STOP instruction and the system returns to the operating
mode as soon as the wait time set using the oscillation stabilization time select register (OSTS)
has elapsed.
The operating statuses in the STOP mode are shown below.
Table 19-4. Operating Statuses in STOP Mode
When STOP Instruction Is Executed While CPU Is Operating on High-Speed
System Clock
When Ring-OSC Oscillation
Continues
When Ring-OSC Oscillation
Stopped
Note 1
When STOP Instruction Is Executed
While CPU Is Operating on Ring-
OSC Clock
STOP Mode Setting
Item
When Subsystem
Clock Used
When Subsystem
Clock Not Used
When Subsystem
Clock Used
When Subsystem
Clock Not Used
When Subsystem
Clock Used
When Subsystem
Clock Not Used
System clock
Only high-speed system clock oscillator oscillation is stopped. Clock supply to the CPU is stopped.
CPU Operation
stopped
Port (latch)
Status before STOP mode was set is retained
16-bit timer/event counter 00
Operation stopped
16-bit timer/event counter 01
Note 2
Operation stopped
8-bit timer/event counter 50
Operable only when TI50 is selected as the count clock
8-bit timer/event counter 51
Operable only when TI51 is selected as the count clock
8-bit timer H0
Operable only when TM50 output is selected as the count clock during 8-bit timer/event counter 50 operation
8-bit timer H1
Operable
Note 3
Operation stopped
Operable
Note 3
Watch timer
Operable
Note 4
Operation stopped Operable
Note 4
Operation stopped Operable
Note 4
Operation stopped
Ring-OSC cannot
be stopped
Note 5
Operable
−
Operable
Watchdog
timer
Ring-OSC can be
stopped
Note 5
Operation stopped
A/D converter
Operation stopped
UART0
UART6
Operable only when TM50 output is selected as the serial clock during TM50 operation
CSI10
Operable only when external SCK10 is selected as the serial clock
Serial interface
CSI11
Note 2
Operable only when external SCK11 is selected as the serial clock
Clock monitor
Operation stopped
Multiplier/divider Operation
stopped
Power-on-clear function
Operable
Low-voltage detection function
Operable
External interrupt
Operable
Notes 1. When “Stopped by software” is selected for Ring-OSC by the option byte and Ring-OSC is stopped by
software (for option bytes, see CHAPTER 24 OPTION BYTE).
2.
µ
PD78F0133H, 78F0134H, 78F0136H, 78F0138H, and 78F0138HD only.
3.
Operable only when f
R
/2
7
is selected as the count clock.
4.
Operable when the subsystem clock is selected.
5.
“Ring-OSC cannot be stopped” or “Ring-OSC can be stopped by software” can be selected by the option
byte.