CHAPTER 8 CLOCK GENERATION FUNCTION
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User’s Manual U15195EJ5V0UD
8.5.4 IDLE mode
(1) Setting and operation status
In the IDLE mode, the clock generator (oscillator and PLL synthesizer) continues to operate, but the supply of
internal system clocks is stopped which causes the overall system to stop.
When IDLE mode is released, the system can be switched to normal operation mode quickly because the
oscillator's oscillation stabilization time or the PLL lockup time do not need to be secured.
The system is switched to IDLE mode by setting the PSC or PSMR register using a store instruction (ST or
SST instruction) or a bit manipulation instruction (SET1, CLR1, or NOT1 instruction) (see
8.5.2 Control
registers
).
In the IDLE mode, program execution is stopped, and the contents of all registers, internal RAM, and ports
are maintained in the state they were in immediately before execution stopped. The operation of on-chip
peripheral I/O units (excluding ports) also is stopped.
Table 8-4 shows the status of each hardware unit in the IDLE mode.
Table 8-4. Operation Status in IDLE Mode
Function Operation
Status
Clock generator
Operating
Internal system clock
Stopped
CPU Stopped
Ports Maintained
On-chip peripheral I/O (excluding ports)
Stopped (CSI0 and CSI1 are operable in slave mode)
Internal data
All internal data such as CPU registers, statuses, data,
and the contents of internal RAM are maintained in the
state they were in immediately before IDLE mode
began.
AD0 to AD15
A16 to A21
High impedance
RD
UWR, LWR
High level output
WAIT Input
(no
sampling)
ASTB High-level
output
CLKOUT Low-level
output
Содержание PD703114
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