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CHAPTER 19 STANDBY FUNCTION
User’s Manual U16228EJ2V0UD
389
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 X1 input clock or Ring-OSC clock.
Caution Because the interrupt request signal is used to clear 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 cleared 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 X1 Input 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 X1 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
Note 6
Operable
Low-voltage detection function
Operable
External interrupt
Operable
Notes 1.
When “Stopped by software” is selected for Ring-OSC by a mask option and Ring-OSC is stopped by
software (for mask options, see
CHAPTER 25 MASK OPTIONS
).
μ
PD780133, 780134, 78F0134, 780136, 780138, and 78F0138 only.
Operable only when f
R
/2
Operable when the subsystem clock is selected.
“Ring-OSC cannot be stopped” or “Ring-OSC can be stopped by software” can be selected by a mask
option.
When “POC used” is selected by a mask option.
2.
3.
4.
5.
7
is selected as the count clock.
6.