topic LowPower Mode(lpidle) in MCX Microcontrollers

LowPower Mode(lpidle)

OneByte — Tue, 01 Apr 2025 06:10:09 GMT

When developing low-power functionality using the RT1052, after the system triggers low-power mode (lpIdle) and wakes up from lpIdle to overrun mode, a specific anomaly is observed during testing: If the module connected to the USB host is active, uSDHC access to eMMC becomes abnormal; if the module on the USB host is inactive, uSDHC can access eMMC normally. How can this issue be troubleshooted?

#rt1052

Re: LowPower Mode(lpidle)

EdwinHz — Wed, 02 Apr 2025 19:35:23 GMT

Hi @OneByte,

Could you please elaborate when you mean that the "uSDHC access to eMMC becomes abnormal"? How is the USB host configured? What about the uSDHC? Does this also happen when transitioning between other power modes?

Re: LowPower Mode(lpidle)

OneByte — Wed, 16 Apr 2025 09:18:45 GMT

When powered on normally, there are no issues. It can be understood that the USB is configured as a host, connected to a module (acting as a device). After entering LP idle mode and then waking up into overrun mode:

If the module connected to the USB host is not powered, normal read/write access to eMMC is possible.

If the module connected via the USB interface is powered, normal read/write access to eMMC becomes unavailable.
Other low-power modes (LP modes) have not been tested."

Re: LowPower Mode(lpidle)

EdwinHz — Tue, 29 Apr 2025 20:57:58 GMT

Hi @OneByte,

Could you share your code to see if there is any issue? What USB device are you using? How could I replicate the issue using our EVK? Have you tested any other low power modes?