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23k external crystal
Posted: Mon Mar 23, 2020 11:23 am
by mrdebug
Hi, I need to use an external crystal oscillator 32k. Can someone suggest me an example on how to use it?
I don't find any example.
Best regards.
Re: 23k external crystal
Posted: Mon Mar 23, 2020 5:31 pm
by ESP_Sprite
How do you mean 'how to use it'? Connect it in hardware, or make use of it in software? In software, there's an option in menuconfig. In hardware, take a look at the
ESP32 Hardware Design Guidelines, chapter 2.1.4.2.
Re: 23k external crystal
Posted: Fri Mar 27, 2020 8:24 am
by mrdebug
Are you saying that it is not necessary to implement it by code but only by the menuconfig option, such as the screenshot below below?
If yes I still reading
"clk: 32 kHz XTAL not found, switching to internal 150 kHz oscillator"
Can you explain the gpio25 as in the screenshot? Is it necessary to use the external crystal?
Re: 23k external crystal
Posted: Fri Mar 27, 2020 3:44 pm
by ESP_Sprite
Yes, that should be all you need to do; deepsleep time keeping etc should automatically switch over to the crystal. I have no idea why your crystal isn't detected, maybe post a picture/schematic of your hardware? Also, GPIO25 is only in the picture because it's a crop of a bigger schematic; it has nothing to do with the crystal.