ADC DMA is not working sporadically in VLPS mode

[nobodyKnows]

Hello,

I use the DMA0 CH0 to transfer the ADC0 conversion data to memory. This works great. But if I use the VLPS sleep mode to save power, then the DMA is sometimes done immediately after it started.

Than the DMA IRQ count goes from 100/sek to 20000/sek and the array is filled with the current ADC0 value.

If this case occurred and I halt the MCU with a breakpoint than everything is working fine again for a few minutes.

If I never enter the VLPS than everything is ok too.

I use a KL26Z256 and the ADC using the internal clock and the DMA is working in async mode - enter VLPS mode should be possible.

I hope someone can help me to solve this issue.

Thanks a lot and best regarads,

Maximilian

[nobodyKnows]

Hello,

thank you for your responds. I noticed that the DMA IRQ does not wakeup the mcu. It seems the IRQ is pending until another IRQ cause an wakeup. How can I configure the DMA to wakeup the MCU?

VD8nDummy.zip - Google Drive 

Best regards,

Maximilian

[jeremyzhou]

Hi Maximilian,

Thank you for your interest in NXP Semiconductor products and the opportunity to serve you.

I was wondering if you can upload the demo and share the process flow to replicate the issue.

I'm looking forward to your reply.
Have a great day,
Ping

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------