![Toshiba TMP91C824F Data Book Download Page 193](http://html.mh-extra.com/html/toshiba/tmp91c824f/tmp91c824f_data-book_428625193.webp)
TMP91C824
91C824-190
The watch dog timer consists of a 22-stage binary counter which uses the system clock (f
SYS
) as the
input clock. The binary counter can output f
SYS
/215, f
SYS
/217, f
SYS
/219 and
fSYS
/221. Selecting one of the
outputs using WDMOD<WDTP1,WDTP0> generates a Watchdog interrupt and outputs watchdog timer
out when an overflow occurs as shown in Figure 3.12.2.
0
WDT Interrupt
WDT Clear
(Soft ware
)
Write clear code
WDT Counter
n
Over flow
Figure 3.12.2 Normal mode
The runaway detection result can also be connected to the Reset pin internally.
In this case, the reset time will be between 22 and 29 states as shown in Figure 3.12.3.
Over flow
WDT Counter
n
WDT Interrupt
22 to 29 states
(44 to 58
µ
s @ f
OSCH
=
16 MHz, f
FPH
=
1 MHz)
Internal Reset
Figure 3.12.3 Reset mode