I'm not sure if I've designed the circuit for PWM power control of the hot plate correctly. The PWM output is a 3.3V MCU. I assume the PWM period 200 ms. The hot plate is 1000W, 220V, 50Hz.
I am unable to communicate with the MCU via UART (115200 bit/s). It looks like the program inside MCU is not running. I think the problem can be probably in not running LSE 32.768kHz crystal oscillator.Is it possible to enable LSE clock on PA8 if I h...
When I changed the RCC_LSEDRIVE_LOW to HIGH it help to start the crystal by touching it by a finger, but the output frequency is 1/2 of 32.768KHz see picture: I noticed that the crystal is soldered upside down i.e. Pin 1 input is going to OSC32_IN an...
Maybe the PCB design (4 layers) is responsible for not working LSE. I didn't expect any problems with 32.768 kHz. U3 is TCVCXO oscillator 26 MHz running well (Vpp = 1V).Crystal used TFX-03 (+/-20ppm, CL=5pF), capacitors 6 pF.STM32L073x, probably STM3...
I created test program in STM32CubeIDE, just to enable LSE on MCO PA8 pin and found out the LSE is not running (as I assumed). When I touch crystal by a finger I get random oscillations I catched on attached oscilloscope screenshots.I don't like to r...
