STM32L011X3 Datasheet, PDF (28/115 Pages) STMicroelectronics – Access line ultra-low-power 32-bit MCU ARM-based Cortex-M0+, up to 16KB Flash, 2KB SRAM, 512B EEPROM, ADC

STM32L011x3/4
Functional overview
3.14.1
3.14.2
3.14.3
General-purpose timers (TIM2, TIM21)
There are three synchronizable general-purpose timers embedded in the STM32L011x3/4
devices (see Table 7 for differences).
TIM2
TIM2 is based on 16-bit auto-reload up/down counter. It includes a 16-bit prescaler. It
features four independent channels each for input capture/output compare, PWM or one-
pulse mode output.
The TIM2 general-purpose timers can work together or with the TIM21 general-purpose
timer via the Timer Link feature for synchronization or event chaining. Its counter can be
frozen in debug mode. Any of the general-purpose timers can be used to generate PWM
outputs.
TIM2 has independent DMA request generation.
This timer is capable of handling quadrature (incremental) encoder signals and the digital
outputs from 1 to 3 hall-effect sensors.
TIM21
TIM21 is based on a 16-bit auto-reload up/down counter. It includes a 16-bit prescaler. It has
two independent channels for input capture/output compare, PWM or one-pulse mode
output. It can work together and be synchronized with TIM2 full-featured general-purpose
timer.
It can also be used as simple timebase and be clocked by the LSE clock source
(32.768 kHz) to provide independent timebase from the main CPU clock.
Low-power Timer (LPTIM)
The low-power timer has an independent clock and is running also in Stop mode if it is
clocked by LSE, LSI or an external clock. It is able to wakeup the devices from Stop mode.
This low-power timer supports the following features:
• 16-bit up counter with 16-bit autoreload register
• 16-bit compare register
• Configurable output: pulse, PWM
• Continuous / one shot mode
• Selectable software / hardware input trigger
• Selectable clock source
– Internal clock source: LSE, LSI, HSI or APB clock
– External clock source over LPTIM1 input (working even with no internal clock
source running, used by the Pulse Counter Application)
• Programmable digital glitch filter
• Encoder mode
SysTick timer
This timer is dedicated to the OS, but could also be used as a standard downcounter. It is
based on a 24-bit downcounter with autoreload capability and a programmable clock
source. It features a maskable system interrupt generation when the counter reaches ‘0’.
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