cc2541定时器和IO配置冲突的问题

我的目的是每秒输出20个周期方波，然后休眠

我在学习swrc257.zip中的例子

发现IO管脚和TIMER冲突

在t3_modulo.c中

#pragma vector = T3_VECTOR
__interrupt void t3_isr(void)
{
    // Clears the module interrupt flag.
    T3OVFIF = 0;

    // Toggles LED1 on SmartRF05EB or CC2544Dongle.
    P0_4 ^= 1;  // Toggle SRF05EB LED1.

    /* Changes the Timer compare value to change the LED blinking interval.
     * The value increases and decreases linearly between 0xFF and 0x02.
     * Writing to the compare register T3CC0 does not take effect on the
     * output compare value until the counter value  is 0x00. (Writing to
     * the compare register T3CC1 takes effect immediately.)
     */
    static int8 sign = -1;
    if (T3CC0 == 0xFF || T3CC0 == 0x02)
    {
        sign *= -1;
    }
    T3CC0 += sign;

    // Clears the CPU interrupt flag.
    T3IF = 0;
}

/*******************************************************************************
* @fn          main
*
* @brief       LED1 and Timer 3 are both initialized. The rest of the program
*              is executed by interrupts from Timer 3.
*
* @param       void
*
* @return      0
*******************************************************************************/
int main(void)
{
    /***************************************************************************
     * Setup clock & tick frequency
     *
     * Configures the Timer tick speed setting, resulting in a Timer tick
     * frequency of 250 kHz.
     */
    CLKCONCMD = (CLKCONCMD & ~CLKCON_TICKSPD) | CLKCON_TICKSPD_250K;

    /***************************************************************************
     * Setup I/O
     *
     * Select P1_0 direction to output
     */
    // LED1 as GPIO.
    P0SEL &= ~BIT4;            
    // Set LED1 as output.
    P0DIR |= BIT4;

    /***************************************************************************
     * Setup interrupt
     *
     * Enables global interrupts (IEN0.EA = 1) and interrupts from Timer 3
     * (IEN1.T3IE = 1).
     */
    EA = 1;
    T3IE = 1;

    /***************************************************************************
     * Timer 3 setup
     *
     * Timer 3 channel 0 compare value. Initiates the Timer terminal count value
     * to 0x02. This value is changed at each Timer compare match interrupt.
     */
    T3CC0 = 0x02;

    /* Timer 3 channel 0 (T3CCTL0) configuration:
     * - Channel 0 interrupt enabled.
     * - Compare mode.
     */
    T3CCTL0 = T3CCTLn_IM | T3CCTLn_MODE;

    /* Timer 3 control (T3CTL) configuration:
     * - Prescaler divider value: 64.
     * - Modulo mode.
     * The Timer is also cleared and started.
     */
    T3CTL = T3CTL_div_64 | T3CTL_MODE_MODULO | T3CTL_CLR | T3CTL_START;

    // Infinite loop.
    while (1);
}

这样程序会跑飞掉

红色部分换成

P0_5^= 1;

P0SEL &= ~BIT5;            

 P0DIR |= BIT5;

就是正常的

我想知道是怎么回事，找了半天也没有相关的文档说明。请指教，谢谢

调试跑飞是正常现象；程序跑飞是内存调用控制出错了，会导致内存调用及代码执行混乱，是非常严重地错误，必须解决！
看Pin Mapping，Timer3是用的P1的端口，和P0口没有关系，先排除其他代码的问题。 

你的原因，应该是对P0.4的复用引起的。而这个复用你可能无意识的，也就是对p0.4的多重的配置。在IAR里 你可以用shift+ctrl+F来查看，你对P0.4的引用情况。输入法保证在英文下使用，最好点上match case 区分大小写

谢谢各位，是管脚不同，影响的外围电路不同造成的。

是硬件问题，谢谢