LPC824 is not waking up from power-down with pin interrupt

[robin_maeder]

Hello

I am trying to wake up the LPC824 from Deep-sleep or Power-down with an external pin but I can not get it working. I tried it according to https://community.nxp.com/t5/LPC-Microcontrollers/LPC824-Power-Down-PIN-Interrupt-wakeup-issue/m-p/1.... I tried it according to the example lpcxpresso824max_power_mode_switch_lpc from SDK. But it does not work either way.

1. Is it possible to use PINT for waking up the LPC824? In the following post they say that pin interrupt is incapable of waking up the MCU from the Deep-sleep or Power-down on LPC11xx? https://community.nxp.com/t5/LPC-Microcontrollers/How-to-wake-up-the-system-from-deep-sleep-mode-wit...

2. Is there another way or example for waking up with pin interrupt?

Thank you and best regards.

[Alice_Yang]

Hello Robin,

What about the phenomenon when you press wake up pin?

How about run project alone without debugger?

Also I will help to test on my side.

Regards,

Alice

[robin_maeder]

Hi Alice

Thank you for your answer. I will try it with the wake-up pin. There is no debugger connected during testing.

Can you say if the wake-up shoud work with PINT interrupt or not?

Regards

[Alice_Yang]

Hello,

"Can you say if the wake-up shoud work with PINT interrupt or not?"

-> Yes, it should be work.

Regards,

Alice

[robin_maeder]

Hello Alice

I got it working with the PINT. The problems were that I called the power down command from inside a PINT callback function and "EnableDeepSleepIRQ(PIN_INTx_IRQn)" was missing.

But now I have another problem. I want to wake up the controller from either the PINT interrupt or the WKT timer. WKT alone works finde, PINT alone works fine. But as soon as I start the WKT timer before going into deep sleep mode, the PINT wakeup does not work anymore.

Any ideas about that phenomenon?

Best regards

[Alice_Yang]

Hello robin_maeder,

I think you can disable the WKT timer in your project, check whether the PIN interrupt can work well.

Regards,

Alice

[robin_maeder]

Hello

But I need the WKT. The microcontroller shall wake up from pin change or every x seconds if there is no pin interrupt. And as already said it works both well, but not at the same time. If I disable the WKT, the pin wakeup works fine. If I enable the WKT, the timer wakeup works fine but the pin wakeup does not work anymore.

Best regards

[Alice_Yang]

Hello robin_maeder,

Please share your project that I can help to test and check on my side.

Regards,

Alice

[robin_maeder · Accepted solution]

I found the problem. Before going into power down I disabled the interrupt callback. After that I had to enable DeepSleepIRQ again.

Best regards

[Alice_Yang]

OK.