STM32F301x6 STM32F301x8
Functional overview
The RTC is an independent BCD timer/counter. It supports the following features:
• Calendar with subsecond, seconds, minutes, hours (12 or 24 format), week day, date,
month, year, in BCD (binary-coded decimal) format.
• Automatic correction for 28, 29 (leap year), 30, and 31 days of the month.
• Two programmable alarms with wake up from Stop and Standby mode capability.
• On-the-fly correction from 1 to 32767 RTC clock pulses. This can be used to
synchronize it with a master clock.
• Digital calibration circuit with 1 ppm resolution, to compensate for quartz crystal
inaccuracy.
• Two anti-tamper detection pins with programmable filter. The MCU can be woken up
from Stop and Standby modes on tamper event detection.
• Timestamp feature which can be used to save the calendar content. This function can
be triggered by an event on the timestamp pin, or by a tamper event. The MCU can be
woken up from Stop and Standby modes on timestamp event detection.
• 17-bit Auto-reload counter for periodic interrupt with wakeup from STOP/STANDBY
capability.
The RTC clock sources can be:
• A 32.768 kHz external crystal
• A resonator or oscillator
• The internal low-power RC oscillator (typical frequency of 40 kHz)
• The high-speed external clock divided by 32.
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