PSoC™ 4 Forum Discussions

[NXTY_Tatebayasi]

Hi, Community

I am considering designing an external crystal (ECO) with PSoC 4100 S Max.

If there is a system reset or an event that causes all clocks to stop (e.g. Stop ), what is the sequence of events that causes the ECO to oscillate next?

Does the ECO automatically resume oscillation when the system returns from those events?

Best Regards,

Chihiro Tatebayashi 

[LinglingG_46 · Accepted solution]

If you call the API "Cy_SysPm_CpuEnterDeepSleep();", then the HFCLK will be disabled.

But after wakeup it will resume.

More please check the linker file:

 https://www.infineon.com/dgdl/Infineon-PSoC_4100S_Max_PSoC4_Architecture_Technical_Reference_Manual_...

[NXTY_Tatebayasi]

Hi, @LinglingG_46  -san

Thank you for telling us about it.
I found out that in case of stopping the clock by calling deep sleep or stop, it is necessary to call an interrupt such as wake up to release those states.
So am I correct in assuming that all stopped clocks can automatically start oscillating (without the user having to call a separate API) once the system satisfies the requirements to return?

Best Regards,

Chihiro Tatebayashi

[LinglingG_46]

Yes, after the system resume from deepsleep state, the clock will automatically start without calling any APIs. Actually, the operation of calling API relies on the clock.

[NXTY_Tatebayasi]

Hi, @LinglingG_46  -san

Thank you very much.
Just solved my problem!

Best Regards,

Chihiro Tatebayashi