Watch Timer Control Register (Wtcon) - Samsung S3C8275X User Manual

WATCH TIMER

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 set 1, bank 1 at address E1H, 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.
Watch timer clock selection bit:
0 = Select main clock divided by 2
1 = Select sub clock (fxt)
Watch timer INT Enable/Disable bit:
0 = Disable watch timer INT
1 = Enable watch timer INT
12-2
Watch Timer Control Register (WTCON)
E1H, Set 1, Bank 1, R/W
MSB .7 .6 .5
7
(fx/128)
Buzzer signal selection bits:
00 = 0.5 kHz
01 = 1 kHz
10 = 2 kHz
11 = 4 kHz
Figure 12-1. Watch Timer Control Register (WTCON)
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X
.4 .3 .2 .1
Watch timer Enable/Disable bit:
0 = Disable watch timer;
clear frequency dividing circuits
1 = Enable watch timer
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
.0 LSB
Watch timer interrupt pending bit:
0 = Interrupt request is not pending
(Clear pending bit when write"0")
1 = Interrupt request is pending