Samsung C8278X ユーザーズマニュアル
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X
WATCH
TIMER
12-3
WATCH TIMER CIRCUIT DIASGRAM
WT INT Enable
WTCON.1
WTCON.2
WTCON.3
WTCON.4
WTCON.5
WTCON.6
Enable/Disable
Selector
Circuit
MUX
WTCON.0
WTINT
WTCON.6
f
W
/2
15
f
W
/2
14
f
W
/2
13
f
W
/2
7
f
W
/64 (0.5 kHz)
f
W
/32 (1 kHz)
f
W
/16 (2 kHz)
f
W
/8 (4 kHz)
(1 Hz)
f
X
= Main clock (where fx = 4.19 MHz)
fxt = Sub clock (32.768 kHz)
f
f
W
= Watch timer frequency
Clock
Selector
Frequency
Dividing
Circuit
f
W
32.768 kHz
fxt
f
LCD
= 2048 Hz
WTCON.7
WTCON.0
(Pending Bit)
8
BUZ (P0.7)
fx/128
Figure 12-2. Watch Timer Circuit Diagram