STM8S103XX STMICROELECTRONICS [STMicroelectronics], STM8S103XX Datasheet - Page 14

• Manufacturer Part Number: STM8S103XX
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Product overview
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Power management
For efficent power management, the application can be put in one four different low-power
modes. You can configure each mode to obtain the best compromise between lowest power
consumption, fastest start-up time and available wakeup sources.
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Watchdog timers
The watchdog system is based on two independent timers providing maximum security to
the applications.
The WDG timer activity is controlled by option bytes. Once activated the watchdog can not
be disabled by the user program without 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.
and an interrupt can optionally be generated.
Configurable main clock output (CCO): This outputs an external clock for use by the
application. Available frequencies are 8 MHz, 4 MHz or 1 MHz.
Wait mode: in this mode, the CPU is stopped, but peripherals are kept running. The
wake-up is performed by an internal or external interrupt or reset.
Fast active halt mode: in this mode, the CPU and peripheral clocks are stopped. An
internal wake-up is generated at programmable intervals by the auto wake up unit
(AWU). The main voltage regulator is kept powered on, so current consumption is more
than in slow active halt mode, but the wake-up time is faster. Wake-up is triggered by
the internal AWU interrupt, external interrupt or reset.
Slow active halt mode: this mode is the same as fast active halt except that the main
voltage regulator is powered off, so the wake up time is slower.
Halt mode: in this mode the microcontroller uses the least power, CPU and peripheral
clocks are stopped, the main voltage regulator is powered off. Wake-up is triggered by
external interrupt or reset.
Timeout: At 16 MHz CPU clock the time-out period can be adjusted between 75 µs up
to 64 ms.
Refresh out of window: The downcounter is refreshed before its value is lower then the
one stored in the window register.
STM8S103xx, STM8S105xx