nested interrupt on msp430

hi Akash!

Normally there is no need to enable interrupts in interrupts. Your description sounds like you maybe never leave the interrupt function because the IFG does not get cleared. Please post your code so we can see what we are talking about.

Dennis

Hi Dennis,

I am sending command over UART to generate PWM with sent steps in UART packet. on each PWM interrupt i am counting

steps and if steps is over i am turning off the timer as well as taking feedback from port 1 with interrupt on falling edge to check status of motor.

here's my sample code.

main() {

    /* enabling global interrupt and port 1 interrupt */

    /* starting timer if command is send over UART to do so*/
    TACCR0 = i_px_uart_cmd->speed;
    TACCR2 = (i_px_uart_cmd->speed >> 1) - 1;

    TACCTL2 = OUTMOD_7 + CCIE;
    TACTL   = TASSEL_2 + MC_1 + TAIE;

}

/* PWM isr routine */

#pragma vector=TIMERA1_VECTOR
__interrupt void pan_pwm_service(void)
{
    static unsigned short int pan_steps;

    if(TACCTL2 & CCIFG) {
        pan_steps++;                                    // if it is pwm interrupt, inc step
        TACCTL2 &= ~CCIFG;
    }
    __bis_SR_register(GIE);

    if (pan_steps > gPanSteps) {
            pan_steps = 0;                             // stepping over

          /* stop timer */
    }
}

/* read status on port */

#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void)
{
    PAN_PORT_IFG &= ~PAN_HOME;
    gPanHOME++;
}

Regards,

Akash

Hi Akash!

This isn't the complete code, right? The main is missing some things. Would you mind to upload everything? Or add as a file?

Dennis