Hi,
While working with RTC smooth calibration on a STM32G070 part, I noticed two strange things:
1st strange thing: When RTC_OUT pin is only driven with the battery backup (no main power) I got 512.18 Hz; however, when the main power is restablished, the frequency drops to 508.38 Hz. I can see these frequencies in both, an oscilloscope and a frequency meter.
2nd strange thing: With the main power restablished, if I attached a multimeter (as a second frequency meter) the RTC_OUT frequency returns back to 512.18 Hz. Then I made an experiment: instead the multimeter, I used a 10KOhm resistor between RTC_OUT and GND and I got the 512.18 Hz again.
Is that possible that RTC_OUT is somehow affecting the crystal circuitry? PC13 has been set as RTC_OUT pin.
Any hints? Am I overlooking sth?
