topic Re: Power Save mem-mode TEST result and question. in i.MX Processors

Power Save mem-mode TEST result and question.

sung-ukjang — Wed, 12 Mar 2014 02:48:53 GMT

We had finished test "mem-mode" on iMX28-EVK.

will wake up to using "PSWITCH" button on Mem-mode.

I have some question.

1. How to check "Mem-mode" or "Power-Off" status??

- because iMX28 is RESET/ is Low status in Mem-mode.

- Can you tell me, still using GPIO config on Mem-mode.

2.We using "PSWITCH" at wake-up source and Power On/Off source.

In IMX28EVK, long push PSWITCH for Power off. still working 32.768KHz sleep clock.

in case is more 12mA to Mem-mode.

root@freescale ~$

root@freescale ~$ release pswitch to power down

pswitch power down

is this normal case??

please help to me!!!

Thanks.

Re: Power Save mem-mode TEST result and question.

AnsonHuang — Wed, 12 Mar 2014 05:46:58 GMT

Hi, Sung-Uk

For question 1:

The mem mode is sleep mode for i.MX28, you can measure the core power voltage, VDDD, there should be about 1.1V on it.

The poweroff mode is to shutdown i.MX28, and the core's power VDDD should be very low, only some leakage.

Not very understand your question 2, can you provide more detail?

Re: Power Save mem-mode TEST result and question.

GraceH — Tue, 18 Mar 2014 07:52:21 GMT

Hi, Sung-Uk

If mem mode you mentioned is entered by command "echo mem > /sys/power/state", actually there is no method to check the difference of mem mode and power off mode. In both of modes,the chip is power down by setting PWD of HW_POWER_RESET.

In MX28 suspend-to-RAM mode, only DRAM is in self-refresh mode and is powered by external circuit; ARM core, on-chip modules, and PLL are off. After entering suspend-to-RAM mode, only power key can resume, then system starts a code boot.

Grace

Re: Power Save mem-mode TEST result and question.

AnsonHuang — Tue, 18 Mar 2014 09:30:03 GMT

OK, Thanks Grace, I just recalled that on i.MX28, the default mode is standby, and the mem mode is mapped to another mode that all modules are off except DRAM, please refer to Grace's answer, she is right, I forgot that I did NOT enable the mem mode on i.MX28.

Re: Power Save mem-mode TEST result and question.

sung-ukjang — Wed, 19 Mar 2014 06:58:35 GMT

OK, Thanks for your support.

Re: Power Save mem-mode TEST result and question.

YixingKong — Fri, 13 Jun 2014 08:45:43 GMT

Sung-Uk

Had your issue got resolved? If yes, we are going to close the discussion in 3 days. If you still need help, please feel free to reply with an update to this discussion.

Thanks,

Yixing

Re: Power Save mem-mode TEST result and question.

YixingKong — Tue, 24 Jun 2014 08:44:41 GMT

Sung-Uk

This discussion is closed since no activity. If you still need help, please feel free to reply with an update to this discussion, or create another discussion.

Thanks,

Yixing