s3c72m9 Samsung Semiconductor, Inc., s3c72m9 Datasheet - Page 233

• Manufacturer Part Number: s3c72m9
• Description: The S3c72m5/s3c72m7/s3c72m9 Single-chip Cmos Microcontroller Has Been Designed For High Performance Using Samsung S
• Manufacturer: Samsung Semiconductor, Inc.

S3C72M5/C72M7/C72M9/P72M9 (Preliminary Spec)
F
The following code shows real-time clock and interrupt processing for key inputs to reduce power consumption. In
this example, the system clock source is switched from the main system clock to a subsystem clock and the LCD
display is turned on:
KEYCLK
CLKS1
CIDLE
PROGRAMMING TIP — Reducing Power Consumption for Key Input Interrupt Processing
DI
CALL
SMB
LD
LD
LD
LD
SMB
BITR
BITR
BITS
BITS
CALL
BTSTZ
JR
CALL
EI
RET
IDLE
NOP
NOP
NOP
JPS
MA2SUB
15
EA,#00H
P4,EA
A,#3H
IMODK,A
0
IRQW
IRQK
IEW
IEK
WATDIS
IRQK
CIDLE
SUB2MA
CLKS1
; Main system clock
; All key strobe outputs to low level
; Select K0–K7 enable
; Execute clock and display changing subroutine
; Subsystem clock
; Engage idle mode
main system clock switch subroutine
subsystem clock switch subroutine
POWER-DOWN
8-5