
ML62Q1000 Series User's Manual
Chapter 10 Watchdog Timer
FEUL62Q1000
10-2
10.1.1 Features
•
Eight types of overflow periods can be chosen (7.8 ms, 15.6 ms, 31.3 ms, 62.5 ms, 125 ms, 500 ms, 2 s, or 8 s)
•
Two types of use are available:
・
Window function disabled mode
The WDT counter can always be cleared. The WDT interrupt is generated when the first counter overflow occurs,
and the WDT reset is generated when the second counter overflow occurs.
・
Window function enabled mode
The periods during which WDT counter clear is enabled and disabled respectively can be set. The WDT reset is
generated when the first counter overflow occurs, and the WDT invalid clear reset is generated when the counter
is cleared in the period during which WDT counter clear is disabled.
Table 10-1 Watchdog Timer Operation Modes
Mode
Event in overflow
WDT invalid clear reset
First
Second
Window function disabled
mode
WDT interrupt
WDT reset
-
Window function enabled
mode
WDT reset
-
Generation enabled
•
The following items can be chosen by the code option. See the Chapter 26 "Code Option" for details of the code
option.
・
Enabling/disabling the WDT timer operation
・
Operation clock of the WDT counter (32 dividing of low-speed clock LSCLK, WDTCLK RC1K oscillation)
[Note]
Ÿ
WDT is the function used to monitor the CPU runaway. Its function as an ordinary timer is not
guaranteed.
Ÿ
The watchdog timer is undetectable to all the abnormal operations. Even if the CPU loses control, the
watchdog timer is undetectable to the abnormality in the operation state in which the WDT counter is
cleared. It is recommended that the WDT counter is cleared at one place in the main loop of the program
as a fail-safe.
Ÿ
WDT can be operated based on the clock independent of the system clock by using RC1K oscillation for
the WDTCLK, resulting in further improvement of safety. However, it is recommended to choose LSCLK
if high accuracy of the frequency is required, since the RC1K oscillation is less accurate than the
LSCLK.
Содержание ML62Q1000 Series
Страница 17: ...Chapter 1 Overview...
Страница 112: ...Chapter 2 CPU and Memory Space...
Страница 154: ...Chapter 3 Reset Function...
Страница 166: ...Chapter 4 Power Management...
Страница 196: ...Chapter 5 Interrupts...
Страница 248: ...Chapter 6 Clock generation Circuit...
Страница 274: ...Chapter 7 Low Speed Time Base Counter...
Страница 291: ...Chapter 8 16 Bit Timer...
Страница 320: ...Chapter 9 Functional Timer FTM...
Страница 382: ...Chapter 10 Watchdog Timer...
Страница 402: ...Chapter 11 Serial Communication Unit...
Страница 456: ...Chapter 12 I2 C Bus Unit...
Страница 491: ...Chapter 13 I2 C Master...
Страница 512: ...Chapter 14 DMA Controller...
Страница 531: ...Chapter 15 Buzzer...
Страница 550: ...Chapter 16 Simplified RTC...
Страница 559: ...Chapter 17 GPIO...
Страница 594: ...Chapter 18 External Interrupt Function...
Страница 612: ...Chapter 19 CRC Generator...
Страница 632: ...Chapter 20 Analog Comparator...
Страница 644: ...Chapter 21 D A Converter...
Страница 655: ...Chapter 22 Voltage Level Supervisor...
Страница 676: ...Chapter 23 Successive Approximation Type A D Converter...
Страница 709: ...Chapter 24 Regulator...
Страница 714: ...Chapter 25 Flash Memory...
Страница 743: ...Chapter 26 Code Option...
Страница 750: ...Chapter 27 LCD Driver...
Страница 788: ...Chapter 28 On Chip Debug Function...
Страница 795: ...Chapter 29 Safety Function...
Страница 813: ...Appendix A...
Страница 881: ...Revision History...