关于omap-l138的定时器的问题

只看该作者 · 2011-8-2 13:05

最近入手OMAP-138，我想用DSP核实现一个定时中断功能。参考SEED提供的开发包，写了一个测试代码。发现，将TIMER0配置成32位，非关联模式后，TIMER3:4运行正常，但是TIMER1:2不运行。
我的代码设置代码如下：
uint32_t USTIMER0_init(void)
{
// configure timer 0 for free run.
// 32-bit unchained mode, timer3:4 /12 prescaler.

// enable muxed pins as gpio outputs and disable all related interrupts.
// would need to also setup the pinmux register to select the gpio
// function of these pins in order to use as gpio.
// TMR0->GPINT_GPEN = GPENO12 | GPENI12;
// TMR0->GPDATA_GPDIR = GPDIRO12 | GPDIRI12;

// stop and reset timer.
TMR0->TGCR = 0x00000000;
TMR0->TCR = 0x00000000;

// disable interrupts and set emulation to free run.
TMR0->INTCTLSTAT = 0;
SETBIT(TMR0->EMUMGT, SOFT | FREE);

// config timer0 in 32-bit unchained mode.
// remove timer0 - 3:4 from reset.
SETBIT(TMR0->TGCR, PRESCALER(TIMER_DIV - 1) | TIMMODE_32BIT_UNCHAINED /*| TIM34RS*/ );

// init timer0 - 1:2 period....use full range of counter.
TMR0->TIM34 = 0x00000000;
TMR0->PRD34 = 0x00000000;
// TMR0->PRD34 = 0xFFFFFFFF;

TMR0->TIM12 = 0x00000000;
TMR0->PRD12 = 0x00000000;
// start timer0 - 3:4.
// SETBIT(TMR0->TCR, ENAMODE34_CONT);

return (ERR_NO_ERROR);
}

void USTIMER0_delay(uint32_t in_delay)
{
uint32_t regData;
#if 0

// stop the timer, clear int stat, and clear timer value.
CLRBIT(TMR0->TGCR, TIM34RS);
TMR0->TCR = 0x00000000;
SETBIT(TMR0->INTCTLSTAT, PRDINTSTAT34);
TMR0->TIM34 = 0x00000000;

// setup compare time.

TMR0->PRD34 = TICKS_PER_US * in_delay;

// start timer1 - 3:4 to run once up to the period.
SETBIT(TMR0->TCR, ENAMODE34_ONETIME);
SETBIT(TMR0->TGCR, TIM34RS);

// wait for the signal that we have hit our period.
while (!CHKBIT(TMR0->INTCTLSTAT, PRDINTSTAT34));
#else
// stop the timer, clear int stat, and clear timer value.
CLRBIT(TMR0->TGCR, TIM12RS);
TMR0->TCR = 0x00000000;
SETBIT(TMR0->INTCTLSTAT, PRDINTSTAT12);
TMR0->TIM12 = 0x00000000;

// setup compare time.
TMR0->PRD12 = TICKS_PER_US * in_delay;

CLRBIT(TMR0->TCR,CLKSRC12);
CLRBIT(TMR0->TCR,TIEN12);

// start timer1 - 3:4 to run once up to the period.
SETBIT(TMR0->TCR, ENAMODE12_ONETIME);
SETBIT(TMR0->TGCR, TIM12RS);

// wait for the signal that we have hit our period.
while (!CHKBIT(TMR0->INTCTLSTAT, PRDINTSTAT12));
#endif
}

主函数

main()
{
USTIMER0_init();
printf("the timer0 test start\n" );
USTIMER0_delay(100);
printf("the timer0 test end\n");
}

如果使用timer3:4来实现，这个测试函数就可以走完，如果用timer1:2来做的话，函数就始终画红语句处。
我也根据TI，定时器的资料上配置了内部时钟源，禁止了内部时钟源开关，（画蓝处）但就是始终停在那里，不往下运行！
请教一下，这是什么问题啊！！，还需要配置什么位置吗？