CCS/MSP430FR5969: LPM4

harikrishna paritala

Tool/software: Code Composer Studio

hi this is harikrishna....

currently i am working on the low power modes..for better current consumption i am using LPM4 in my project..and i refer the MSP430FR5969 user guide and data sheeet..it says that in LPM4 only external interrupt will only wake_up from the low_power_mode...but in my project i am using external 32768HZ(ACLK=32K) crystal and RTC is Still running with that 32K..how it is possible..or RTC will run in LPM4 mode...or my MSP is not working properly..really i don't no what is happen..can anybody tell me the problem..

over 8 years ago

0 Mitch Ridgeway over 8 years ago

TI__Expert 6635 points

Hi Harikrishna,

I'm going to look further into this and provide information as soon as I can.

Thanks,

Mitch

0 Lukas Badura over 8 years ago in reply to Mitch Ridgeway

TI__Expert 4695 points

Can you please share your code how you are setting the LPM4?

0 Mitch Ridgeway over 8 years ago

TI__Expert 6635 points

Hey Harikrishna,

It sounds like you may not be getting into LPM4. If you do not disable the RTC in the SW before you try to go into LPM4, the RTC clock will not allow the MCU to go into LPM4. It looks like you may be going into LPM3 (even if you call the __bis_SR_register(LPM4_bits) function in your code).

In order to insure that you are going into LPM4, disable the RTC before going into LPM4.

If you really need the extra low power, it looks like you can run the RTC in LPM3.5 on the FR5969 device. If LPM3 will meet your power needs, this may be a simple option.

Thanks,

Mitch

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CCS/MSP430FR5969: LPM4