UPD78F0078GK-9ET-A Renesas Electronics America, UPD78F0078GK-9ET-A Datasheet - Page 221

• Manufacturer Part Number: UPD78F0078GK-9ET-A
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0078GK-9ET-A

• Lead Free Status / Rohs Status: Supplier Unconfirmed

11.4.2 Interval timer operation
preset count value when bit 4 (WDTM4) of the watchdog timer mode register (WDTM) is set to 0.
select register (WDCS). When bit 7 (RUN) of WDTM is set to 1, the watchdog timer operates as an interval timer.
flag (WDTPR) are validated and the maskable interrupt request (INTWDT) can be generated. Among the maskable
interrupts, INTWDT has the highest priority at default.
the STOP mode is set, clear the interval timer and then execute the STOP instruction.
The watchdog timer operates as an interval timer that generates interrupt requests repeatedly at an interval of the
The interval time of the interval timer is selected with bits 0 to 2 (WDCS0 to WDCS2) of the watchdog timer clock
When the watchdog timer operates as an interval timer, the interrupt mask flag (WDTMK) and priority specification
The interval timer continues operating in the HALT mode but it stops in STOP mode. Thus, set RUN to 1 before
Cautions 1. Once bit 4 (WDTM4) of WDTM is set to 1 (this selects the watchdog timer mode), the interval
Note Expanded-specification products of PD780078 Subseries only.
Remark f
2. The interval time just after setting WDTM may be shorter than the set time by up to 2
3. When the subsystem clock is selected for the CPU clock, the watchdog timer count operation
X
: Main system clock oscillation frequency
timer mode is not set unless RESET is input.
seconds.
is stopped.
2
2
2
2
2
2
2
2
12
13
14
15
16
17
18
20
/f
/f
/f
/f
/f
/f
/f
/f
X
X
X
X
X
X
X
X
Interval Time
Table 11-3. Interval Timer Interval Time
CHAPTER 11 WATCHDOG TIMER
User’s Manual U14260EJ4V0UD
488 s
977 s
1.95 ms
3.91 ms
7.82 ms
15.6 ms
31.2 ms
125 ms
When Operated at
f
X
= 8.38 MHz
341 s
682 s
1.36 ms
2.73 ms
5.46 ms
10.9 ms
21.8 ms
87.3 ms
When Operated at
f
X
= 12 MHz
Note
219
8
/f
X