I am using the ESP32-WROOM-32E module, and I see that the RTC clock can be driven externally thru the XTAL_32K_P input (IO 32). A 32.768 kHz oscillator is specified. I am considering changing to a 1 PPM clock for more accurate timing, but is it possible to use a different frequency? For example, the...

I do this with the ESP32. Spestano is correct, you just have to load into a buffer. To give you an example, I define char myCertificate[N_BYTES_CERTIFICATE]; where N_BYTES_CERTIFICATE needs to be about 1500, and then read and load the certificate like this myFServer.read2String(SPIFFS, REMOTE_CERT_F...

Hi igrr Thanks for your response. Just to make sure I understand, could you confirm that when you say "underlying XTAL clock source" this means the 40 MHz external XTAL? I understand the issue with the PLL. I believe this will add maximum jitter around the range of 1 x 40 MHz period, or 25 ns. If yo...

I am trying to do accurate timing using the ESP32 64 bit counter which use the 80 MHz APB clock. I need accuracies of 1 ppm or better. If I use an external 40 MHz crystal with 1 ppm accuracy will the APB clock now have 1 ppm accuracy? Is the APB clock derived directly from the external 40 MHz crysta...