About wake-up from VLLS modes and interrupt handling

[gauravbanyal]

Hello,

I am running the "power_mode_switch" example on the FRDM-KL03 board.

When I set the core to VLLS modes (VLLS_0 and VLLS_3) and I use the SW2 to wake up the core I intend to monitor the interrupt handlers LLWU_IRQHandler() and APP_WAKEUP_BUTTON_IRQ_HANDLER().  

I have added prints inside LLWU_IRQHandler() and the APP_WAKEUP_BUTTON_IRQ_HANDLER(). When I press SW2 to exit the VLLS state, I see the print from the function LLWU_IRQHandler() but not from the other although these two are configured to react on the same interrupt source.

Whats the reason for this? In my application, I need to use the BOARD_SW2_IRQ_HANDLER() handler to do some stuff. But looks like it does not get called. Please explain.

[xiangjun_rong · Accepted solution]

Hi,

Pls refer to Table 7-2. Module operation in low-power modes in Chapter 7 in RM of KL03, in VLLS mode, the NVIC interrupt module is OFF, but LLWU is in full function state, that is why that the LLWU ISR is entered and VLLSx mode is exitted once you press hardware button on the FRDM-KL03 board.

In conclusion, in theVLLS mode,  LLWU is in full function state, but NVIC is in off state.

Hope it can help you

BR

XiangJun Rong