STM32F101XF datasheet(19/117 Pages) STMICROELECTRONICS

19 / 117 page

DocID16553 Rev 5

19/117

STM32F101xF, STM32F101xG

Description

2.3.17

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 are forty-two 16-bit

registers used to store 84 bytes of user application data when VDD power is not present.

They are not reset by a system or power reset, and they are not reset when the device

wakes up from the Standby mode.

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

an external 512 Hz output to compensate for any natural quartz 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.

2.3.18

Timers and watchdogs

The XL-density STM32F101xx access line devices include up to ten general-purpose

timers, two basic timers, two watchdog timers and a SysTick timer.

Table 4: STM32F101xF and STM32F101xG timer feature comparison compares the

features of the general-purpose and basic timers.

General-purpose timers (TIMx)

There are 10 synchronizable general-purpose timers embedded in the STM32F101xF and

STM32F101xG XL-density access line devices (see Table 4 for differences).

•

TIM2, TIM3, TIM4, TIM5

There are up to 4 synchronizable general-purpose timers (TIM2, TIM3, TIM4 and TIM5)

embedded in the STM32F101xF and STM32F101xG access 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

Table 4. STM32F101xF and STM32F101xG timer feature comparison

Timer

Counter

resolution

Counter

type

Prescaler factor

DMA

request

generation

Capture/compare

channels

Complementary

outputs

TIM2, TIM3,

TIM4, TIM5

16-bit

Up,

down,

up/down

Any integer between

1 and 65536

Yes

TIM9, TIM12

16-bit

Any integer between

1 and 65536

TIM10, TIM11,

TIM13, TIM14

16-bit

Any integer between

1 and 65536

TIM6, TIM7

16-bit

Any integer between

1 and 65536

Yes

STM32F101XF Datasheet(PDF) 19 Page - STMicroelectronics

STM32F101XF Datasheet(HTML) 19 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 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL