What modification is necessary to run the Power Mode Switch Demo for iMXRT1052 in FreeRTOS assuming FreeRTOS is running in low power tickless mode?
I'm trying to do this - but code is crashing when I add the following to my application after Board Clock / Peripheral init:
LPM_Init();
LPM_OverDriveRun();1. Does altering the clocks w/ the LPM code breaks the freertos low power tickless logic (ie - low power tickless timer executes and tries to run WFI when the device might already be in low power state?
2. Does the Power Mode Switch Demo doesn't account for other peripherals? Our device is using lpspi, lpuart, lpi2c, usb, semc, flexspi... Do I need to do extra stuff just to run in LPM_OverDriveRun? (I want to eventually run in LPM_PowerModeSysIdle mode)
3. Any insight regarding restrictions if using LPM code from the ^^^ demo in a FreeRTOS project would be much appreciated.
3a. Should I freeze all tasks / timers before changing LPM modes?
3b. Do I need to completely de-init all peripherals and re-init just to change modes from run to idle?
4. Does LPM_EnableWakeupSource need to be executed every time you want to go to sleep, or can it just be executed once @ startup assuming you have a dedicated push button.
Can you use the same GPIO IRQ for wake up and standard ISR code? (ie - is it OK for me to override void GPIO1_Combined_16_31_IRQHandler(void) in my code - this won't break the wake-up logic?)
5. I noticed the Power Mode Switch Demo actually alters the USB related PLLs - I thought this was NOT recommended when running code from XIP? (as per here from clock_config.c):
One further update, danielchen@fsl:
i've updated the demo on github to run on the Arch Mix Seeed board now.
The same issue happens on there: 
so I"m thinking it's something related to that this demo is meant only for hyperflash and i'm missing a step for regular 133MHz NOR FLASH.
Do you have a Seeed board you can test with there?
Or know what's missing in the demo when ported for qspi NOR FLASH?
Hi danielchen@fsl,
On the Seeed board:
The the evkbimxrt1050_power_mode_switch_ca demo works without any error if I Link Application to RAM, so it appears the issue is specifically related to running from FLASH.
Can you confirm the demo works for you on the RT1050 EVK board when linked to flash?
Are you able to test the RT1050 EVK w/ QSPI NOR FLASH (like the one from the RT1020EVK)?
For the errors I'm seeing when running from FLASH:
When I update specific.c for what I believe to be proper FlexSPI Speeds for this board (133MHz), and then run, AFTER I choose a mode which requires changing the clocks -> I get the error I put in the image in the previous post, segfault:
Active Fault @ power_mode_switch.c line 413;
BFARVALID (7) BusFault Address Register BFAR valid flag
PRECISERR (1) Precise data bus error
FORCED (30) - forced hard fault
Register LR is at LPM_FullSpeedRun() at memory location 0x60002ABB
Register PC is at PowerModeSwitchTask() at memory location 0x600039A8
Here's teh screenshot again:
If I DON'T change the FlexSPI div settings in specific.c (which would mean overclocking the FlexSPI FLASH by 2x) - also an imprecise data bus error (2) forced hard fault, LR at 0x600026A9.
Could you please confirm the demo works for you from FLASH - like the IS25LP064A-BLE FLASH used on the rt1020evk?
