KW41Z Wake up problem
I am developing an application about transfering data via BLE 4.0 using KW41Z board. I am quite successful to do so but the app only works correctly within some minutes.
I set connection event period of BLE: 2s.
I used LPTMR to hardware trigger ADC 16bit. When ADC conversion completes, it triggers DMA to move data from ADC result register to a defined area of memory. LPTMR period: 20ms, DMA interupts MCU after 200 ADC conversions (4s).
MCU works at VLPS mode when it is not interrupted by DMA or BLE thread. Everything is fine until an unknown source wakes MCU up and it seems to be weird that DMA interrupt and BLE connection interrupt still work and at the end of ISR of these interrupt I put "PWR_AllowDeviceToSleep();" function that I want MCU to come back to VLPS mode but IT DOES NOT WORK.
I must mention that I control every other sources of the interrupt and facilitate not to let these interruption happen.
I use an instrument that can record Board current. As you can see in the attached image, after normal running, at 08:26 power increases and never goes down. It means MCU gets out of VLPS mode and never comes back.
Can anybody give me any advice? I will much appreciate it. Thank you very much in advance
