Z8018x Family
MPU User Manual
37
Table 5. Power-Down Modes (Z8S180/Z8L180-Class Processors Only)
Power-
Down
Modes
On-Chip
CPU Core I/O
Recovery
CLKOUT Source
Recovery Time
(Minimum)
Osc.
SLEEP
Stop
Running
Running Running
RESET,
1.5 Clock
Interrupts
I/O STOP
Running
Stop
Stop
Running Running
Running Running
Running Stop
By
–
Programming
SYSTEM
STOP
Stop
RESET,
Interrupts
1.5 Clock
IDLE †
Stop
Stop
RESET,
8 + 1.5 Clock
Interrupts,
BUSREQ
17
STANDBY † Stop
Stop
Stop
Stop
RESET,
2
+ 1.5 Clock
Interrupts,
BUSREQ
(Normal
Recovery)
6
2 + 1.5 Clock
(Quick Recovery)
† IDLE and STANDBY modes are only offered in the Z8S180. The minimum recovery time can
be achieved if INTERRUPT is used as the Recovery Source.
STANDBY Mode
The Z8S180/Z8L180 is designed to save power. Two low-power
programmable power-down modes have been added:
•
•
STANDBY mode
IDLE mode
The STANDBY/IDLE mode is selected by multiplexing bits 1 and 3 of
the CPU Control Register (CCR, I/O Address = 1FH).
To enter STANDBY mode:
UM005001-ZMP0400
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