Do I understand right and MCU can be totally crystalless ? And supports whole declared temperature range ?
PLL0 can use FRO_12MHz and generate 100 or 150 Mhz clocks without any problems.
SPi and I2C can use FRO_12Mhz for clocking ( SPI speed can be 10Mhz ?).
RTC can own FRO32KHz oscillator but it may be not so precise for keep calendar time.
Is this so ? How to calculate possible drift while 1 week ?
What can be problems if no any crystals is not in use ?