Hello @ESP_Angus, sorry for awaking this thread from the death, but I have a question: since a few years we use a 3V3 HCMOS 2ppm/40MHz Oscillator (ECS-TXO-2520-33-400-AN-TR) , directly coupled to the XTAL_P pin, XTAL_N left floating. However, just recently I found, that the Hardware Design Guideline...

Hi, I am also interested in this. Also maybe: what are the differences between calling esp_restart() / esp_reboot() and EN-toggle?

I have a custom board running a SD card in 4 wire mode. Sometimes I get "sdmmc_read_blocks failed (263)" error which is hard to reproduce. The SD-Traces are kept relatively short and the power supply is good. Next week I have the chance to measure some stuff. What are the software and/or hardware ca...

Mhh, I see this oscillator thing more like an "all or nothing"-problem. I mean it's a digital signal running through a 4-5mm bodge wire. The Vcc and GND connections are fine and it's properly decoupled. The 40 MHz Signal has slew rate control, so it should not radiate any harmonics and the short wir...

That's correct!

That is why we shifted to using oscillators, since our products experience a wide temperature range. This one has a maximum error of 2ppm +-2ppm over temp range if I remember correctly.

It's not a crystal, it's an oscillator (thus no load caps, only one decoupling). I've verified this botch. The antenna here was hand assembled, the other units are machine assembled. Since I tested all units in the lab I am not sure if this could even be the issue (especially the oscillator thing, s...

It's to protect a bodge correcting swapped pins on the oscillator (40 MHz, 2ppm TCXO).

Hi Angus, thanks for your reply! Sadly as the point of installation is very remote, testing various things (with case open, WROOM32, more distance) is not easy. This is why I was hoping for some remote testing possibilities. Regarding the RF-Cal: Since they calibrate the whole frontend and do (I thi...

No idea on this? Is there anything more I can provide to help here? Are there other support channels in order to get deeper information/documentation about the RF calibration?