Filter
Top Products
WATCH TIMER S3C9228/P9228
12-2
WATCH TIMER CONTROL REGISTER (WTCON)
The watch timer control register, WTCON is used to select the input clock source, the watch timer interrupt time
and Buzzer signal, to enable or disable the watch timer function. It is located in page 0 at address DAH, and is
read/write addressable using register addressing mode.
A reset clears WTCON to "00H". This disable the watch timer and select fx/128 as the watch timer clock.
So, if you want to use the watch timer, you must write appropriate value to WTCON.
Buzzer signal selection bits:
00 = 0.5 kHz
01 = 1 kHz
10 = 2 kHz
11 = 4 kHz
Watch Timer Control Register (WTCON)
DAH, R/W
.7 .6 .5 .4 .3 .2 .1 .0MSB LSB
Watch timer Enable/Disable bit:
0 = Disable watch timer;
clear frequency dividing circuits
1 = Enable watch timer
Not used
Watch timer speed selection bits:
00 = Set watch timer interrupt to 1 s
01 = Set watch timer interrupt to 0.5 s
10 = Set watch timer interrupt to 0.25 s
11 = Set watch timer interrupt to 3.91 ms
Watch timer clock selection bit:
0 = Main clock divided by
2
7
(fx/128)
1 = Sub clock (fxt)
Watch timer INT Enable/Disable bit:
0 = Disable watch timer INT
1 = Enable watch timer INT
Figure 12-1. Watch Timer Control Register (WTCON)