xDot Oscillator/Clock

[Katelyn Jobes]

Hi,

I am developing a schematic for a custom board featuring the xDot that will be using I2C. I am wondering if the xDot features an internal clock or if an external clock is required. Page 22 of the Developer Guide mentions the following four clock pins, but I have not found any additional information on them.

PC14-OSC32_IN = Real-time clock
PC15-OSC32_OUT = Real-time clock
PH0-OSC_IN = High speed system clock
PH1-OSC_OUT = High speed sytem clock

Does the xDot require an external clock? If so, which pins should be used?

Thanks

[Peter Ferland]

That table is reporting what is done with all of the connections to the STM32L151CC processor. Those 4 pins are connected on the xDot itself to external (to the processor) clocks. 32.768kHz for the RTC and 24MHz for HSE. If you are using mbed 5 the xDot target sets up these clocks automatically.

• This reply was modified 7 years, 3 months ago by Peter Ferland.

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