NO:
W90P710 Programming Guide
VERSION:
2.0
PAGE:
154
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed, distributed or reproduced without permission
from Winbond.
Table No.: 2005-W90P710-11-A
12 Timers
12.1 Overview
The W90P710 Timer module includes two channels, TIMER0 and TIMER1, which allow user to
easily implement a counting scheme. Each channel has independent clock source. The input clock is
divided by an 8-bit pre-scalar and then referenced by a 24-bit down counter. When the counter counts
down to zero, the Timer will assert an interrupt request if the interrupt is enabled. A general software-
counting scheme is to set a software counter, and add 1 to it upon every interrupt.
The Timer module also includes a watchdog timer. It supports the system restart if the system
goes into problem. This prevents system from hanging for an infinite period of time. The watchdog
timer is a free running counter with programmable time-out intervals. When the specified time internal
interval expires, it asserts an interrupt to inform software to reset the counter. If the counter doesn’t be
reset during 512 WDT clocks, the watchdog timer will generate a system restart signals to reset the
whole system. Normally, the program should implement a task to periodically reset the counter if the
watchdog timer is enabled.
