stm8af6199 STMicroelectronics, stm8af6199 Datasheet - Page 18

• Manufacturer Part Number: stm8af6199
• Description: Automotive 8-bit Mcu, With Up To 128 Kbytes Flash, Eeprom, 10-bit Adc, Timers, Lin, Can, Usart, Spi, I 2c, 3 V To 5.5 V
• Manufacturer: STMicroelectronics

Product overview
5.7
5.7.1
5.7.2
18/100
Timers
Watchdog timers
The watchdog system is based on two independent timers providing maximum security to
the applications.
The WDG timer activity is controlled by the application program or option bytes. Once the
watchdog is activated, it cannot be disabled by the user program without a reset.
Window watchdog timer
The window watchdog is used to detect the occurrence of a software fault, usually
generated by external interferences or by unexpected logical conditions, which cause the
application program to abandon its normal sequence.
The window function can be used to trim the watchdog behavior to match the application
perfectly.
The application software must refresh the counter before time-out and during a limited time
window.
A reset is generated in two situations:
1.
2.
Independent watchdog timer
The independent watchdog peripheral can be used to resolve processor malfunctions due to
hardware or software failures.
It is clocked by the 128 kHz LSI internal RC clock source, and thus stays active even in case
of a CPU clock failure. If the hardware watchdog feature is enabled through the device
option bits, the watchdog is automatically enabled at power-on, and generates a reset
unless the key register is written by software before the counter reaches the end of count.
The IWDG time base spans from 60 µs to 1 s. It can be adjusted by setting the registers of
the 7-bit prescaler and 8-bit down-counter.
Auto wake-up counter
●
●
Timeout
Refresh out of window: The downcounter is refreshed before its value is lower then the
one stored in the window register.
Used for auto wake-up from active halt mode.
Clock source: Internal 128 kHz internal low frequency RC oscillator or external clock.
STM8AF61xx, STM8AF51xx