How to implement timeout timer functionality in MSP430F2370

Use some reference codes available on TI website for MSP430F2370.

you will have to use one of the available timers -> load the count -> start the timer -> timer interrupt is generated.

The count will be the number of clock cycles of the clock used by the timer module.

Hi Chethu Gowda,

This is the file included in Stack. I am not able to understand how to use these default apis given by TI. They are using these apis in finding RFID tags UID.

//===============================================================

extern u08_t i_reg;
extern u08_t irq_flag,flag;

//===============================================================
// NAME: void Msp430f23x0DileyMillisecond (u08_t n_ms)
//
// BRIEF: Is used to create delays.
//
// INPUTS:
// Parameters:
// u08_t n_ms delay time in ms
//
// OUTPUTS:
//
// PROCESS: [1] do loop of 1 ms duration as often as required
//
// CHANGE:
// DATE WHO DETAIL
// 23Nov2010 RP Original Code
//===============================================================

void
Msp430f23x0DelayMillisecond(u32_t n_ms)
{
while (n_ms--)
{
__delay_cycles(DELAY_1ms); // clock speed in Hz divined by 1000
}
}

//===============================================================
// NAME: void Msp430f23x0CounterSet (void)
//
// BRIEF: Is used to set the timerA.
//
// INPUTS:
//
// OUTPUTS:
//
// PROCESS: [1] set timerA
//
// CHANGE:
// DATE WHO DETAIL
// 23Nov2010 RP Original Code
//===============================================================

void
Msp430f23x0CounterSet(void)
{
TACTL |= TACLR;
TACTL &= ~TACLR; // reset the timerA
TACTL |= TASSEL0 + ID1 + ID0; // ACLK, div 8, interrupt enable, timer stopped

TAR = 0x0000;
TACCTL0 |= CCIE; // compare interrupt enable

}

//===============================================================
// NAME: void Msp430f23x0OscSel (u08_t mode)
//
// BRIEF: Is used to select the oscilator.
//
// INPUTS:
// Parameters:
// u08_t mode crystal oscillator or DCO for
// main clock
//
// OUTPUTS:
//
// PROCESS: [1] select the oscilator
//
// CHANGE:
// DATE WHO DETAIL
// 23Nov2010 RP Original Code
//===============================================================

void
Msp430f23x0OscSel(u08_t mode)
{

u08_t ii1 = 0;

if (mode == 0x00) // select crystal oscilator
{
BCSCTL1 |= XTS + XT2OFF; // ACLK = LFXT1 HF XTAL
BCSCTL3 |= LFXT1S1; // 3 – 16MHz crystal or resonator
// the TRF796x sys_clk pin works as ocillator
// it is set to 6.78 MHz (= 13.56 MHz / 2) in Trf797xInitialSettings()
// turn external oscillator on
do
{
IFG1 &= ~OFIFG; // Clear OSCFault flag
for (ii1 = 0xFF; ii1 > 0; ii1--) // Time delay for flag to set
{
}
} while ((IFG1 & OFIFG) == OFIFG); // OSCFault flag still set?

BCSCTL2 |= SELM1 + SELM0 + SELS; // MCLK = SMCLK = HF LFXT1 (safe)

return;
} // end of IF case

else //select DCO for main clock
{
DCOCTL |= DCO0 + DCO1 + DCO2;
BCSCTL1 |= XT2OFF + XTS + RSEL0 + RSEL1 + RSEL2;

BCSCTL2 &= ~(SELM1 + SELM0 + SELS + DCOR);

return;
}
//_BIC_SR(OSCOFF);
}

//===============================================================
// NAME: void Msp430f23x0TimerAHandler (void)
//
// BRIEF: Is used to handle the interrupts generated by timerA.
//
// INPUTS:
//
// OUTPUTS:
// Globals:
// u08_t i_reg indicates TIMEOUTs
//
//
// PROCESS: [1] handle the interrupts generated by timerA
//
// CHANGE:
// DATE WHO DETAIL
// 23Nov2010 RP Original Code
//===============================================================

#pragma vector=TIMERA0_VECTOR
__interrupt void
Msp430f23x0TimerAHandler(void)
{
u08_t irq_status[4];

STOP_COUNTER;

irq_flag = 0x03;

Trf797xReadIrqStatus(irq_status);

*irq_status = *irq_status & 0xF7; // set the parity flag to 0

if(*irq_status == 0x00 || *irq_status == 0x80)
{
i_reg = 0x00; // timer interrupt
}
else
{
i_reg = 0x01;
}
if(flag==1)
{
flag=2;
}
//__low_power_mode_off_on_exit();
}

//========================================================================================

I am doing this to get a timeout of 100ms, but still unsuccessful.

McuCounterSet(); //set timer A
//COUNT_VALUE = COUNT_1ms * 10; // for 4 ms TIMEOUT
TACCR0 = 2000;
START_COUNTER; // start timer up mode

where: 

#define COUNT_VALUE TACCR0 //counter register
// #define START_COUNTER TACTL |= MC0 + MC1 //start counter in up/down mode
#define START_COUNTER TACTL |= MC1 //start counter in up mode

#define STOP_COUNTER TACTL &= ~(MC0 + MC1) //stops the counter

//---------------------------------------------------------------

#define COUNT_1ms 847
#define COUNT_60ms 0xC684

Ashi

Ashi Gupta said:

am doing this to get a timeout of 100ms, but still unsuccessful.

unsuccessful in getting interrupt or getting exact delay of 100ms.

Ashi Gupta said:

McuCounterSet(); //set timer A
//COUNT_VALUE = COUNT_1ms * 10; // for 4 ms TIMEOUT
TACCR0 = 2000;
START_COUNTER; // start timer up mode

This part looks OK.

Ashi Gupta said:

TACCR0 = 2000;

but this value should give u delay of 500ms.

Thanku..problem resolved with this help.

Ashi