MSP430FR5869: comparater use case on LPM3

Kz777

Expert 7895 points

Part Number: MSP430FR5869

Hi Champs,

We would like to use three port comparator (i.e P1.0,P1.1,P1.2)

According to data sheet , At LPM3, we can't use these three comparator inputat same time.

So, I would like to use these ports as time revision.

First of all connect P1.0 to comparatoer at LPM3 for 200msec. After 200msec, it connect to P1.1 for 200msec,P1.2 for 200msec.

Then, it back to P1.0 for 200msec. (all time is LPM3)

Is it able to realize this use case ?

Regards,

Kz777

over 8 years ago

0 Clemens Ladisch over 8 years ago

Guru 317480 points

You could use a timer to trigger the DMA to write a new value to the comparator control register. Alternatively, use a timer interrupt handler to do the same from code.
In both cases, the CPU goes out of LPM3 to change the control register.

0 Katie Pier over 8 years ago in reply to Clemens Ladisch

TI__Guru* 78241 points

Hi Kz777,

Clemens is correct - there are ways to have time division for usage of a port, but you would have to come out of LPM3 (either to active mode for CPU intervention, or to LPM0 for DMA) in order to change the selected input.

Regards,
Katie

0 Kz777 over 8 years ago in reply to Katie Pier

TI__Expert 7895 points

Hi Clemens, Katie,
Thanks for your information. I cleared it.

Regards,
Kz777

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MSP430FR5869: comparater use case on LPM3