Hyundai Micro Electronics
GMS81C2020/GMS81C2120
21. Power Saving Mode
For applications where power consumption is a critical
factor, device provides four kinds of power saving func-
tions, STOP mode, Subactive mode and Wake-up Timer
mode(Standby mode, Watch mode).
Table 21-1 shows the status of each Power Saving Mode.
Wake-up Timer Mode
Peripheral
STOP Mode
Subactive Mode
Standby Mode
Retain
Watch Mode
Retain
RAM
Control Registers
I/O Ports
Retain
Retain
Retain
Stop
Retain
Retain
Retain
Retain
Retain
Retain
Retain
CPU
Operation
Operation
Stop
Stop
Stop
Timer0
Stop
Operation
Oscillation
Stop
Operation
Stop
Oscillation
Sub Oscillation
Prescaler
Stop
Stop
Oscillation
Operation
Oscillation
÷ 2048 only
Stop
÷ 2048 only
Entering Condition
[WAKEUP]
0
0
1
1
Table 21-1 Power Saving Mode
The power saving function is activated by execution of
STOP instruction and by execution of STOP instruction
after setting the corresponding status (WAKEUP) of
CKCTLR.
we shows the release sources from each Power Saving
Mode
Wake-up Timer Mode
Subactive
Mode
Release Source
STOP Mode
Standby Mode
Watch Mode
RESET
RCWDT
EXT.INT
EXT.INT1
Timer0
O
O
O
O
O
O
O
O
O
X
O
X
O
O
O
O
Table 21-2 Release Sources from Power Saving Mode
Nov. 1999 Ver 0.0
preliminary
73
HYNIX [ HYNIX SEMICONDUCTOR ]
