GMS81C50 Datasheet, PDF (72/99 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCONTROLLERS

HYUNDAI
GMS81C50 Series
14. STANDBY FUNCTION
To save power consumption, there is STOP modes. In this
modes, the execution of program stops.
14.1 Sleep Mode
SLEEP mode can be entered by setting the bit of SLEEP
mode register (SLPM). In the mode, CPU clock stops but
oscillator keeps running. B.I.T and a part of peripheral
hardware execute, but prescalerís output which provide
clock to peripherals can be stopped by program. (Except,
PS10 canít stopped.) In SLEEP mode, more consuming
power can be saved by not using other peripheral hardware
except for B.I.T. By setting ENPCK (peripheral clock con-
trol bit) of CKCTLR (clock control register) to ``0``, pe-
ripheral hardware halted, and SLEEP mode is entered. To
release SLEEP mode by BITR (basic interval timer inter-
rupt), bit10 of prescaler should be selected as B.I.T input
clock before entering SLEEP mode. ``NOP`` instruction
should be follows setting of SLEEP mode for rising pre-
charge time of data bus line.
(ex) setting of SLEEP mode : set the bit of SLEEP
; mode register (SLPM)
NOP
: NOP instruction
7
SLPM
-
SLEEP MODE CONTROL Register
-
-
-
-
-
-
0
SLPM0
W <00F0 h>
SLPM0
0
1
condition
sleep mode release
sleep mode
7
CKCTLR
-
Colck Control Register
0
-
WDTON ENPCK BTCL
BTS2
BTS1
BTS0
W <00C8 h>
ENCPK
0
1
Peripheral Clock
stopped
provided
14.2 STOP MODE
STOP mode can be entered by STOP instruction during
program. In STOP mode, oscillator is stopped to make all
clocks stop, which leads to less power consumption. All
registers and RAM data are preserved. ``NOP`` instruction
should be follows STOP instruction for rising precharge
time of Data Bus line.
(ex) STOP : STOP instruction execution
NOP : NOP instruction
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