MSP430FR6047: UART Rx with USS measurement

Dhinesh S

Part Number: MSP430FR6047

Hello Team,

I want to have the USS running and also need to receive data from UART simultaneously. The UART interrupt doesn't works with the USS measurement on.

I tried disabling the LPM, also tried changing to LPM0 as well. Nothing works. Please provide your inputs.

TIA.

10 months ago

0 Sal Ye 10 months ago

TI__Genius 14655 points

Hi Dhinesh,

Have you tried receiving data using only UART Rx in your current configuration, disable USS, is it working fine?

I want to make sure that there is no incorrect configuration of your UART setting.

B.R.

Sal

0 Dhinesh S 10 months ago in reply to Sal Ye

Prodigy 60 points

Hi Sal,

Yes. I have tried it and it is working.

0 Sal Ye 10 months ago in reply to Dhinesh S

TI__Genius 14655 points

Hi Dhinesh,

There should be nothing in the USS code can disable the UART interrupt, so can you confirm that whether the Rx interrupt flag is asserted and whether there is data in Rx after reception.

B.R.

Sal

0 Dhinesh S 10 months ago in reply to Sal Ye

Prodigy 60 points

Hi Sal,

Moving the system to LPM0 from LPM3 makes the UART interrupt to work.

Regards.

0 Dhinesh S 10 months ago in reply to Dhinesh S

Prodigy 60 points

btw, is this an expected behaviour?

0 Bruce McKenney 10 months ago in reply to Dhinesh S

Guru 93160 points

It sounds like you're using SMCLK (UCSSEL=2 or 3). SMCLK is switched off in LPM3.

You can clock the UART with ACLK (UCSSEL=1), which is active in LPM3, but your bit-rate choices are more limited since ACLK is so slow.

0 Sal Ye 10 months ago in reply to Dhinesh S

TI__Genius 14655 points

Hi Dhinesh,

I think Bruce gives the correct conjecture, please check the clock and take a try.

B.R.

Sal

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MSP430FR6047: UART Rx with USS measurement