General-purpose timers (TIMx)
There are up to 4 synchronizable general-purpose timers (TIM2, TIM3, TIM4 and TIM5)
embedded in the STM32F103xC, STM32F103xD and STM32F103xE performance line
devices. These timers are based on a 16-bit auto-reload up/down counter, a 16-bit prescaler
and feature 4 independent channels each for input capture/output compare, PWM or one-
pulse mode output. This gives up to 16 input captures / output compares / PWMs on the
largest packages.
The general-purpose timers can work together with the advanced-control timer via the Timer
Link feature for synchronization or event chaining. Their counter can be frozen in debug
mode. Any of the general-purpose timers can be used to generate PWM outputs. They all
h***e independent DMA request generation.
These timers are capable of handling quadrature (incremental) encoder signals and the
digital outputs from 1 to 3 hall-effect sensors.
Basic timers TIM6 and TIM7
These timers are mainly used for DAC trigger generation. They can also be used as a
generic 16-bit time base.
Independent watchdog
The independent watchdog is based on a 12-bit downcounter and 8-bit prescaler. It is
clocked from an independent 40 kHz internal RC and as it operates independently from the
main clock, it can operate in Stop and Standby modes. It can be used either as a watchdog
to reset the device when a problem occurs, or as a free running timer for application timeout
management. It is ha***are or software configurable through the option bytes. The counter
can be frozen in debug mode.
Window watchdog
The window watchdog is based on a 7-bit downcounter that can be set as free running. It
can be used as a watchdog to reset the device when a problem occurs. It is clocked from the
main clock. It has an early warning interrupt capability and the counter can be frozen in
debug mode.
SysTick timer
This timer is dedicated to real-time operating systems, but could also be used as a standard
down counter. It features:
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A 24-bit down counter
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Autoreload capability
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Maskable system interrupt generation when the counter reaches 0.
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Programmable clock source