Commit 45c8997e authored by Daniel Friesel's avatar Daniel Friesel
Browse files

msp430fr5994: add experimental support for 32kHz operation via LFXT

parent bebc6a4b

src/arch/msp430fr5994lp/arch.cc

+13 −1
Original line number Diff line number Diff line
@@ -37,6 +37,8 @@ void Arch::setup(void) 
	// 8MHz DCO

	CSCTL0_H = CSKEY >> 8;

	CSCTL1 = DCOFSEL_0;

#elif F_CPU == 32768UL

	CSCTL0_H = CSKEY >> 8;

#else

#error Unsupported F_CPU

#endif
@@ -50,7 +52,7 @@ void Arch::setup(void) 
	CSCTL0_H = 0;





#ifdef WITH_LOOP

#if defined(WITH_LOOP) || F_CPU == 72368UL

	// enable LXFT for RTC

	CSCTL0_H = CSKEY >> 8;

	CSCTL4 &= ~LFXTOFF;
@@ -82,6 +84,12 @@ void Arch::setup(void) 
	TA0CTL |= TACLR;

#endif /* TIMER_US */



#if F_CPU == 32768UL

	CSCTL0_H = CSKEY >> 8;

	CSCTL2 = SELA__LFXTCLK | SELS__LFXTCLK | SELM__LFXTCLK;

	CSCTL0_H = 0;

#endif



#if defined(WITH_LOOP) || defined(TIMER_S)

	// 1s per wakeup for loop. Independent of SMCLK/F_CPU

	TA1CTL = TASSEL__ACLK | ID__8 | MC__UP;
@@ -153,6 +161,10 @@ void Arch::sleep_ms(unsigned int const ms) 
	TA3CTL = TASSEL__SMCLK | ID__8; // /8

	TA3EX0 = 0; // /1 -> /8 (125 kHz)

	TA3CCR0 = ms * 125;

#elif F_CPU == 32768UL

	TA3CTL = TASSEL__SMCLK | ID__8; // /8

	TA3EX0 = 0; // /1 -> /8 (4.096 kHz)

	TA3CCR0 = ms * 4;

#else

#error Unsupported F_CPU

#endif /* F_CPU */

src/arch/msp430fr5994lp/driver/stdout.cc

+6 −0
Original line number Diff line number Diff line
@@ -32,6 +32,12 @@ void StandardOutput::setup() 
	UCA0CTLW0 = UCSWRST | UCSSEL__SMCLK;

	UCA0MCTLW = 0x5500;

	UCA0BR0 = 8;

#elif F_CPU == 32768UL

	// Limited to 9600 Baud

	// 32768 / 9600 == 3.413333 -> UCOS16 = 0, UCBR0 = 3, UCBRF0 = 0, UCBRS0 = 0x92 ("0.4003")

	UCA0CTLW0 = UCSWRST | UCSSEL__SMCLK;

	UCA0MCTLW = 0x9200;

	UCA0BR0 = 3;

#else

#error Unsupported F_CPU

#endif