STM32F103X8 datasheet(12/84 Pages) STMICROELECTRONICS

12 / 84 page

Description

STM32F103xx

12/84

RTC (real-time clock) and backup registers

The RTC and the backup registers are supplied through a switch that takes power either on

VDD supply when present or through the VBAT pin. The backup registers (ten 16-bit

registers) can be used to store data when VDD power is not present.

The real-time clock provides a set of continuously running counters which can be used with

suitable software to provide a clock calendar function, and provides an alarm interrupt and a

periodic interrupt. It is clocked by a 32.768 kHz external crystal, resonator or oscillator, the

internal low power RC oscillator or the high speed external clock divided by 128. The

internal low-power RC has a typical frequency of 40 kHz. The RTC can be calibrated using

an external 512 Hz output to compensate for any natural crystal deviation. The RTC features

a 32-bit programmable counter for long term measurement using the Compare register to

generate an alarm. A 20-bit prescaler is used for the time base clock and is by default

configured to generate a time base of 1 second from a clock at 32.768 kHz.

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 time out

management. It is hardware 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 for OS, but could also be used as a standard down counter. It

features:

●

A 24-bit down counter

●

Autoreload capability

●

Maskable system interrupt generation when the counter reaches 0.

●

Programmable clock source

General purpose timers (TIMx)

There are up to 3 synchronizable standard timers embedded in the STM32F103xx

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 12 input captures / output

compares / PWMs on the largest packages. They can work together with the Advanced

Control Timer via the Timer Link feature for synchronization or event chaining.

The counter can be frozen in debug mode.

Any of the standard timers can be used to generate PWM outputs. Each of the timers has

independent DMA request generations.

STM32F103X8 Datasheet(PDF) 12 Page - STMicroelectronics

STM32F103X8 Datasheet(HTML) 12 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84

Datasheet Download

Link URL