CD00253742 Datasheet, PDF (19/120 Pages) STMicroelectronics – XL-density performance line ARM-based 32-bit MCU

STM32F103xF, STM32F103xG
Description
The DMA can be used with the main peripherals: SPI, I²C, USART, general-purpose, basic
and advanced-control timers TIMx, DAC, I²S, SDIO and ADC.
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
V_DD supply when present or through the V_BAT pin. The backup registers are forty-two 16-bit
registers used to store 84 bytes of user application data when V_DD 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 STM32F103xx performance line devices include up to two advanced-control
timers, up to ten general-purpose timers, two basic timers, two watchdog timers and a
SysTick timer.
Table 4 compares the features of the advanced-control, general-purpose and basic timers.
Table 4. STM32F103xF and STM32F103xG timer feature comparison
Timer
Counter Counter
resolution type
Prescaler factor
DMA request Capture/compare Complementary
generation
channels
outputs
TIM1, TIM8
16-bit
Up,
down,
up/down
Any integer between
1 and 65536
Yes
4
Yes
TIM2, TIM3,
TIM4, TIM5
16-bit
Up,
down,
up/down
Any integer between
1 and 65536
Yes
4
No
TIM9, TIM12 16-bit
Up
Any integer between
1 and 65536
No
2
No
TIM10, TIM11
TIM13, TIM14
16-bit
Up
Any integer between
1 and 65536
No
1
No
TIM6, TIM7 16-bit
Up
Any integer between
1 and 65536
Yes
0
No
Doc ID 16554 Rev 3
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