CCS: 7

Helder Nfuca

Other Parts Discussed in Thread: MSP430FR2311

Tool/software: Code Composer Studio

Guys I would like to configure the MSP430FR2311, The RTC needs to generate 8s interrupt to wake up the device from LPM4, how should i configure it to do so?

RTCMOD = 10 -8;
RTCCTL = RTCSS__VLOCLK | RTCSR | RTCPS__10 | RTCIE;

is it correct??

over 8 years ago

0 Nathan Siegel over 8 years ago

TI__Genius 10980 points

Hi,

Your RTCMOD value will depend on the rate of your RCT clock source value. Please see the RTC examples in the following example code files for more detail: www.ti.com/.../getliterature.tsp

Regards,
Nathan

0 Ryan Brown1 over 8 years ago

TI__Guru**** 222427 points

Please refer to the msp430fr231x_RTC code examples provided by TI: www.ti.com/.../slac708

VLOCLK is roughly 10 kHz with variance over temperature. 10/10000*3 = 3 ms, I recommend using a RTCPS value of /1000 and RTCMOD value of 79 so that you end up at 1000/10000*80 = 8 s. I would also recommend using a XT1CLK 32 kHz external crystal if dependable timing is required for your application.

Regards,
Ryan

0 Helder Nfuca over 8 years ago in reply to Ryan Brown1

Prodigy 50 points

Thanks, it shed me some light.

But just one question, why use an RTCMOD of 79? why not the whole 80? (sorry I'm new in this program)

0 Ryan Brown1 over 8 years ago in reply to Helder Nfuca

TI__Guru**** 222427 points

One tick is required to roll over from 79 to 0, therefore 80 in total for a full period.

Regards,
Ryan

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