SPC input to WUU not waking device

[robert_hines]

[Working with MCXN947]

I have voltage detect interrupts enabled (resets disabled) in SPC in both low-power and active modes (resets disabled, bandgaps enabled).

SPC0->ACTIVE_CFG:  3f101615
SPC0->LP_CFG:      3f221515
SPC0->VD_IO_CFG:   0000000a
SPC0->VD_SYS_CFG:  0000000a
SPC0->VD_CORE_CFG: 0000000a

I've enabled SPC as a wake-up source in the WUU (WUU->ME bit is set).

The SPC interrupt works in active mode, but not in power-down mode, i.e. the processor doesn't wake to handle the SPC interrupt.

[Alice_Yang]

Hi @robert_hines 

1. The wake-up latency from Power-down mode is expected to be longer than the interrupt response time in Active mode. In Power-down mode, most of the MCU is in a static state. One of the trade-offs of entering a deeper low-power mode is the increased latency when entering and exiting that mode.

2. Regarding the issue where the interrupt only occurs once, I suspect there may be an issue in the application code handling. Could you please refer to the power_mode_switch example included in the SDK and compare the implementation with your code?

If the issue still persists, please provide a simple project that can reproduce the problem on the FRDM-MCXN947 board. I will be happy to investigate it further.

Thank you.

BR

Alice

[robert_hines]

I think it may be working, but there's a large difference in the response between active and power-down mode.  In active mode, the SPC interrupt will respond more quickly and go off repeatedly, but from power-down mode, it takes much longer to trigger the interrupt and it only triggers once.