kl02z SACKERR condition

[donweier]

Hello,

     I'm trying to work through a problem I'm having with the kinetis kl02z32vfg4. I'm trying to implement low power by operating in VLPR(which is working fine) and entering VLPS when there are no tasks for the mcu to complete. The problem I'm having is this: whenever I strobe the WFI instruction, there is a reset condition. By checking the RCM_SRS1 register I'm able to see that the reset source is a Stop Mode Acknowledge Error. I did some searching around on the forums and found this thread: K10 SACKERR reset occur after executing an WFI instruction but even after removing the bus clock to the SPI, I2C, TPM, and PORT modules and delaying several clock cycles before calling WFI, I'm getting the reset with the SACKERR flag set. I'm wondering if there's something I'm missing. Are there other peripherals that can cause the error? Is there a way I can see which module is failing to acknowledge the STOP instruction?

Thank you all for any help that you can give me,

Don

[donweier]

Well I've just solved it. I'll post my mistake in case somebody else has this problem in the future. The core expects an acknowledge from all the relevant peripherals outlined in the other post, not just the ones that are clocked byt the SIM control registers. In an effort to reduce power to a minimum I left some peripherals unclocked (one I2C bus and one timer module as well as a few others). When I enabled all peripherals before calling WFI the mcu was able to successfully enter the VLPS mode.