Improve ESP32 power down code

[josesimoes]

Description

• Improve ESP32 power down code.

Motivation and Context

• Need to follow the new goto power down workflow.

How Has This Been Tested?

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: José Simões [email protected]

[nfbot]

Hi @josesimoes,

I'm nanoFramework bot.
Thank you for your contribution!

A human will be reviewing it shortly. 😉

[josesimoes]

Please validate this. I added that call to esp_wifi_stop() following a recommendation that is on the EPS32 documentation.

[AdrianSoundy]

I tried this and although code looks ok it didn't seem to work. The only change i would make is to call the nanoHAL_Uninitialize() instead of esp_wifi_stop() before the esp_deep_sleep_start() as that should stop the wifi( not sure if it does at the moment, but it should do. Can sort that out later ).

The CPU_SetPowerMode(PowerLevel_type powerLevel) function doesn't get called. I added some tracing and it doesn't seem to exit the g_CLR_RT_ExecutionEngine.Execute()

[josesimoes]

@AdrianSoundy I've pushed the changes as you've suggested. It's now calling nanoHAL_Uninitialize_C().

As for not going into SetPowerMode() it can be either because the execution engine doesn't exit (strange because the code is common) or the flags on that if statement before are being changed after being set in NativeStartDeepSleep___STATIC__nanoFrameworkHardwareEsp32EspNativeError() which looks even more weird...

[josesimoes]

@AdrianSoundy there was a bug in the call to nanoHAL_Uninitialize_C() please give this another try.

[AdrianSoundy]

I have now tested this and it seems to be working.
Test code - Goes to deep sleep for 2 minutes then reboots

       public static void Main()
        {
            Console.WriteLine("Hello world! "+ Sleep.GetWakeupCause().ToString() );

            Console.WriteLine("Deep sleep in 10 seconds "+ DateTime.UtcNow.ToString());
            
            Thread.Sleep(10000);

            Sleep.EnableWakeupByTimer(new TimeSpan(0, 2, 0));
 
            Console.WriteLine("Start deep sleep " + DateTime.UtcNow.ToString());
            Sleep.StartDeepSleep();
            Console.WriteLine("after deep sleep, should not see");

            Thread.Sleep(Timeout.Infinite);
        }

[AdrianSoundy]

LGTM