RTC_C configuration in MSP430F6779 with UART

Abhi Pandya

Hello,

I am currently working on following code. But I couldn't read the RTCSEC. Also when I debug it, I found that CPU is not reaching ISR. I want to send RTC registers on UART.

void main(void)

{
WDTCTL = WDTPW | WDTHOLD; // Stop WDT

UCS_config(); // Clock Source system

/***************RTC Configuration with Calender Mode*********************/
RTCCTL0_H = RTCKEY_H; // Unlock RTC_C module
RTCCTL0_L |= RTCTEVIE | RTCAIE | RTCRDYIE; // Enable RTC time event, alarm event,
// read ready interrupt
RTCCTL1 |= RTCBCD | RTCHOLD; // RTC enable BCD mode, RTC hold

RTCYEAR = 0x2015; // Year 2015->0x2015
RTCMON = 0x08; // Month August->0x08
RTCDAY = 0x28; // Day 28th->0x28
RTCDOW = 0x05; // Day of week Friday-> 0x05
RTCHOUR = 0x24; // Hour from 24 Hour Mode
RTCMIN = 0x59; // Minute
RTCSEC = 0x55; // Seconds
/*****Alarm Registers*****/
RTCADOWDAY = 0x3; // RTC Day of week alarm = 0x2
RTCADAY = 0x22; // RTC Day Alarm = 0x22
RTCAHOUR = 0x23; // RTC Hour Alarm
RTCAMIN = 0x45; // RTC Minute Alarm

RTCCTL1 &= ~(RTCHOLD); // Start RTC calendar mode
RTCCTL0_H = 0; // Lock RTC_C module

P1DIR &= ~BIT6;
P1OUT |= BIT6;

eUSCI_A0_UART_config();

__bis_SR_register(GIE);

}

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)

#pragma vector=USCI_A0_VECTOR
__interrupt
void USCI_A0_ISR(void)

#elif defined(__GNUC__)

void __attribute__ ((interrupt(USCI_A0_VECTOR))) USCI_A0_ISR (void)

#else

#error Compiler not supported!

#endif
{
switch (__even_in_range(UCA0IV, 8))

{

case USCI_NONE:
break; // No interrupt

case USCI_UART_UCRXIFG: // RXIFG

break;

case USCI_UART_UCTXIFG:

code for send data on UART....

break; // TXIFG

case USCI_UART_UCSTTIFG:
break; // TTIFG

case USCI_UART_UCTXCPTIFG:
break; // TXCPTIFG

default: break;

}

void eUSCI_A0_UART_config(void)
{
// Setup P3.0 UCA0RXD, P3.1 UCA0TXD
P3SEL0 |= BIT0 | BIT1; // Set P3.0, P3.1 to non-IO

P3DIR |= BIT0 | BIT1; // Enable UCA0RXD, UCA0TXD

// Setup eUSCI_A0

UCA0CTLW0 |= UCSWRST; // **Put state machine in reset**

UCA0CTLW0 |= UCSSEL_1; // CLK = ACLK

UCA0BRW=0x0003; // Clock Prescaler Setting baud-rate 32kHz/9600=3.41 (see User's Guide)

UCA0MCTLW = 0x5300; // Modulation UCBRSx=0x53, UCBRFx=0

UCA0CTLW0 &= ~UCSWRST; // **Initialize USCI state machine**

UCA0IE |= UCTXIE|UCRXIE; // Enable USCI_A0 RX/TX interrupt

}

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=RTC_VECTOR
__interrupt void rtc_isr(void)

//#elif defined(__GNUC__)
//void __attribute__ ((interrupt(RTC_VECTOR))) rtc_isr (void)
//#else
//#error Compiler not supported!
//#endif
{
switch (__even_in_range(RTCIV, 16))
{
case RTCIV_NONE: // No interrupts
break;
case RTCIV_RTCOFIFG: // RTCOFIFG
break;
case RTCIV_RTCRDYIFG: // RTCRDYIFG
{
volatile int sec=RTCSEC;
P1OUT ^= 0x40; // Toggles P1.6 every second
}
break;
case RTCIV_RTCTEVIFG: // RTCEVIFG
__no_operation(); // Interrupts every minute
break;
case RTCIV_RTCAIFG: // RTCAIFG
__no_operation(); // Interrupts every alarm event
break;
case RTCIV_RT0PSIFG: // RT0PSIFG
break;
case RTCIV_RT1PSIFG: // RT1PSIFG
break;
// case 14: break; // Reserved
case 16: break; // Reserved
default: break;
}
}

Please kindly resolve this issue. Is it because I have included two ISRs?

Thank you.

Abhi

over 10 years ago

0 Jace H over 10 years ago

TI__Guru 56685 points

Hello Abhi,

From your main () , I do not see any main loop or a LPM is being entered. This means when you reach the end of your program, the device just stops for it has nothing else to execute. I would place a while(1); at the end of main or go into LPM and see where you get from there.

Regards,
JH

0 Abhi Pandya over 10 years ago in reply to Jace H

Intellectual 320 points

Hello Jace,

But in my hardware there is no provision for any backup power or secondary supply. So I want to ask that still I need to go for LPM routine? I found the sample code from the MSPWARE for the RTC_C implementation. Find my edited code as follows:

main()
{
WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer

// Initialize LFXT1
UCSCTL6 &= ~(XT1OFF); // Enable XT1
UCSCTL6 |= XCAP_3; // Internal load cap

P3OUT &= ~BIT0; // Clear P3.0 output

P3DIR |= BIT0; // Set P3.0 as output

RTC_config();

__bis_SR_register(GIE);

__no_operation();

return 0;
}

void RTC_config()
{
RTCCTL0_H = 0xA5;
RTCCTL1 |= RTCBCD | RTCMODE;
RTCYEAR = 0x2015;
RTCMON = 0x05;
RTCDAY = 0x01;
RTCDOW = 0x02;
RTCHOUR = 0x01;
hr=RTCHOUR;
RTCMIN = 0x03;
min=RTCMIN;
RTCSEC = 0x00;
sec=RTCSEC;
RTCCTL0_L |= RTCTEVIE | RTCAIE | RTCRDYIE;
RTCCTL1 &= ~(RTCHOLD);
X=RTCCTL0_L;
sec=RTCSEC;
min=RTCMIN;
hr=RTCHOUR;
}

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=RTC_VECTOR
__interrupt void rtc_isr(void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(RTC_VECTOR))) rtc_isr (void)
#else
#error Compiler not supported!
#endif
{
switch (__even_in_range(RTCIV, 16))
{
case RTCIV_NONE: // No interrupts
break;
case RTCIV_RTCOFIFG: // RTCOFIFG
break;
case RTCIV_RTCRDYIFG: // RTCRDYIFG
P3OUT ^= 0x01; // Toggles P3.0 every second
break;
case RTCIV_RTCTEVIFG: // RTCEVIFG
__no_operation(); // Interrupts every minute
break;
case RTCIV_RTCAIFG: // RTCAIFG
__no_operation(); // Interrupts every alarm event
break;
case RTCIV_RT0PSIFG: // RT0PSIFG
break;
case RTCIV_RT1PSIFG: // RT1PSIFG
break;
case 16: break; // Reserved
default: break;
}
}

But, even in this implementation, I am unable to pass current value to the var sec,min,hr from the already initialized RTC_registers. It keeps on reading 0(zero). Can you debug what is the problem poised?

Thank you.

Regards,
Abhi

0 Jace H over 10 years ago in reply to Abhi Pandya

TI__Guru 56685 points

Abhi,

You have to either go into an LPM state or have a while(1) [or some other main loop] within your main function. Without this, you hit the return 0 and exit the main function and the device is no longer executing code.

Example:

main()

{

//Initialization Code

//RTC initialization

//Application Code

__bis_SR_register(GIE); //Enable Interrupts, if you want to  you can go to LPM instead here as well

while(1);

__no_operation(); // Code should never get here

}

This would be step one in debugging your code. For further hints on the RTC_C module, please see our TI Design:

http://www.ti.com/tool/TIDM-AUX-MODULE

Also, when posting code on the forums, please use the Rich Text Format Link on the bottom right hand side. From this advanced menu, please use the Insert Code Snippet function in order to format code for easier reading.

Regards,

0 Abhi Pandya over 10 years ago in reply to Jace H

Intellectual 320 points

Hi Jace,

Thank you for the insight. I had followed your instruction and try for following code.

int main(void)
{
    WDTCTL = WDTPW | WDTHOLD;	// Stop watchdog timer
	
    // Initialize LFXT1
    UCSCTL6 &= ~(XT1OFF);                   // Enable XT1
    UCSCTL6 |= XCAP_3;                      // Internal load cap

    P3OUT &= ~BIT0;                         // Clear P3.0 output
    P3DIR |= BIT0;                          // Set P3.0 as output

    RTC_config();

    __bis_SR_register(GIE);
    while(1)
    __no_operation();
}

void RTC_config()
{
	// Configure RTC_C
	    RTCCTL0_H = RTCKEY_H;           // Unlock RTC_C module
	    RTCCTL1 |= RTCBCD;            	// RTC enable BCD mode, RTC hold
	    RTCYEAR = 0x2015;                       	// Year = 0x2015 -> 2015
	    RTCMON = 0x05;                          	// Month = 0x09 -> September
	    RTCDAY = 0x01;                          	// Day = 0x01 -> 1st
	    RTCDOW = 0x02;                          	// Day of week -> 0x02
	    RTCHOUR = 0x01;                         	// Hour = 0x13
	    hr=RTCHOUR;
	    RTCMIN = 0x30;                          	// Minute = 0x30
	    min=RTCMIN;
	    RTCSEC = 0x00;
	    sec=RTCSEC;			// Seconds = 0x00
	    RTCCTL0_L |= RTCTEVIE | RTCAIE | RTCRDYIE;
	    RTCCTL1 &= ~(RTCHOLD);                  	// Start RTC calendar mode
	  // RTCCTL0_H = 0;                          	// Lock RTC_C module
	    X=RTCCTL0_L;
	    sec=RTCSEC;
            min=RTCMIN;
	    hr=RTCHOUR;
}


#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=RTC_VECTOR
__interrupt void rtc_isr(void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(RTC_VECTOR))) rtc_isr (void)
#else
#error Compiler not supported!
#endif
{
    switch (__even_in_range(RTCIV, 16))
    {
        case RTCIV_NONE:                    // No interrupts
            break;
        case RTCIV_RTCOFIFG:                // RTCOFIFG
            break;
        case RTCIV_RTCRDYIFG:               // RTCRDYIFG
            {
            	P3OUT ^= 0x01;                  // Toggles P3.0 every second
            }
            break;
        case RTCIV_RTCTEVIFG:               // RTCEVIFG
            __no_operation();               // Interrupts every minute
            break;
        case RTCIV_RTCAIFG:                 // RTCAIFG
            __no_operation();               // Interrupts every alarm event
            break;
        case RTCIV_RT0PSIFG:                // RT0PSIFG
            break;
        case RTCIV_RT1PSIFG:                // RT1PSIFG
            break;
//      case 14: break;                     // Reserved
        case 16: break;                     // Reserved
        default: break;
    }
}

but still debugger shows the value of the var=0 even after starting it. Can you tell me what could be the problem?

Thank you.

Abhi

0 Jace H over 10 years ago in reply to Abhi Pandya

TI__Guru 56685 points

Abhi,

I do not see your code form the above post. Just as a sanity check here, how are you powering AUXVCC3 here? Are you working on a target board or the HW platform of the TI-Design mentioned in an earlier post? Please remember, without proper powering of AUXVCC3 in these devices, the RTC_C module is not powered on.

Regards,
JH

0 Jace H over 10 years ago in reply to Jace H

TI__Guru 56685 points

Closing this thread due to inactivity.

Regards,
JH

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RTC_C configuration in MSP430F6779 with UART

http://www.ti.com/tool/TIDM-AUX-MODULE