Tisham Dhar

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9 years, 6 months ago.

What capacitance/size crystal ?

Hi,

With the choice of 18pF caps I assume a 9pF or 10pF Crystal was used. What physical size ? Part number ?

Cheers,

whatnick

Question relating to:

Last updated: 08 Apr 2014
Lib to switch the clock speed of the ST Nucleo to 84MHz. The internal RC oscillator is multiplied with the PLL. clock, f401, Nucleo

1 Answer

Peter Drescher
9 years, 6 months ago.

The HSE oscillator is not critical. The mbed lib expect a 8MHz crystal, HC49US housing, 18-20pF, thru hole. You don't need this patch program for 84 MHz. The actual mbed lib will use 84 MHz as default !

The 32.768kHz LSE oscillator is critical, because ST has build a very low power oscillator. You need a crystal with a load capacitance of 6pF. The caps ~ 6.8pF. (Digikey SER2417CT-ND will work)