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CHAPTER 18 STANDBY FUNCTION
User’s Manual U16315EJ3V1UD
351
18.2 Standby Function Operation
18.2.1 HALT mode
(1) HALT mode
The HALT mode is set by executing the HALT instruction. HALT mode can be set regardless of whether the CPU
clock before the setting was the X1 input clock, internal oscillation clock, or subsystem clock.
The operating statuses in the HALT mode are shown below.
Table 18-2. Operating Statuses in HALT Mode (1/2)
When HALT Instruction Is Executed While CPU Is
Operating on X1 Input Clock
When HALT Instruction Is Executed While CPU Is
Operating on Internal Oscillation Clock
When Internal Oscillation
Clock Continues
When Internal Oscillation
Clock Stopped
Note 1
When X1 Input Clock
Oscillation Continues
When X1 Input Clock
Oscillation Stopped
HALT 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
When
Subsystem
Clock Used
When
Subsystem
Clock Not
Used
System clock
Clock supply to the CPU is stopped
CPU
Operation stopped
Port (output latch)
Status before HALT mode was set is retained
16-bit timer/event counter 00
Operable
Operation not guaranteed
8-bit timer/event counter 50
Operable
Operation not guaranteed when count clock other than
TI50 is selected
8-bit timer/event counter 51
Operable
Operation not guaranteed when count clock other than
TI51 is selected
8-bit timer H0
Operable
Operation not guaranteed when count clock other than
TM50 output is selected during 8-bit timer/event
counter 50 operation
8-bit timer H1
Operable
Operation not guaranteed when count clock other than
fR/2
7 is selected
Watch timer
Operable
Note 2
Operable
Note 2
Operable
Note 3 Operation not
guaranteed
Operable
Note 3
Operation not
guaranteed
Internal oscillator
cannot be stopped
Note 4
Operable
Operable
Watchdog
timer
Internal oscillator
can be stopped
Note 4
Operation stopped
A/D converter
Operable
Operation not guaranteed
UART0
Operable
UART6
Operable
Operation not guaranteed when serial clock other than
TM50 output is selected during TM50 operation
Serial
interface
CSI10
Operable
Operation not guaranteed when serial clock other than
external SCK10 is selected
Clock monitor
Operable
Operation stopped
Operable
Operation stopped
Power-on-clear function
Note 5
Operable
Low-voltage detection function
Operable
External interrupt
Operable
Notes 1.
When “Stopped by software” is selected for the internal oscillator by a mask option and the internal
oscillator is stopped by software (for mask options, see CHAPTER 24 MASK OPTIONS).
2.
Operable when the X1 input clock is selected.
3.
Operation not guaranteed when other than subsystem clock is selected.
4.
“Internal oscillator cannot be stopped” or “Internal oscillator can be stopped by software” can be selected
by a mask option.
5.
When “POC used” is selected by a mask option.