Strongchen，Help。还是使用多通道PIT问题？

PIT, Strongchen, Help, 通道

这是我写的例程，还是发现这3个通道不能同时使用。估计是它们之间相互干涉了，我用的是9S12XDP512，4M晶振。
#include /* common defines and macros */
#include /* derivative information */
#pragma LINK_INFO DERIVATIVE "mc9s12xdp512"

void SetupPITimer (void)
{
/* time-out period = (PITMTLD0 + 1) * (PITLD0 + 1) / Fbus */
PITMUX &= ~(0x01|0x02|0x04); /* T0,T1 and T2 count with MT0 time base (0.25 us)*/
PITCE |= (0x01|0x02|0x04); /* enable PIT channel 0,1,2 */
PITCFLMT |= 0x80; /* PITE=1 (enable PIT) */
}

void EnablePIT0 (void)
{
PITTF |= 0x01; /* clear PIT channel 0 flag */
PITMTLD0 = 99; /* MT0 load value (divides bus clock) */
PITLD0 = 19999; /* T0 load value (5 ms) */
PITCFLMT |= 0x01; /* PFLMT0=1 (reload MT0) */
PITFLT |= 0x01; /* force reload of PIT channel 0 */
PITINTE |= 0x01; /* enable PIT channel 0 interrupt */
}

void EnablePIT1 (void)
{
PITTF |= 0x02; /* clear PIT channel 1 flag */
PITMTLD0 = 99; /* MT0 load value (divides bus clock) */
PITLD1 = 19999; /* T1 load value (5 ms) */
PITCFLMT |= 0x02; /* PFLMT0=1 (reload MT0) */
PITFLT |= 0x02; /* force reload of PIT channel 1 */
PITINTE |= 0x02; /* enable PIT channel 1 interrupt */
}

void EnablePIT2 (void)
{
PITTF |= 0x04; /* clear PIT channel 1 flag */
PITMTLD0 = 99; /* MT1 load value (divides bus clock) */
PITLD2 = 19999; /* T1 load value (5 ms) */
PITCFLMT |= 0x04; /* PFLMT0=1 (reload MT0) */
PITFLT |= 0x04; /* force reload of PIT channel 1 */
PITINTE |= 0x04; /* enable PIT channel 1 interrupt */
}

void IoInit (void)
{

DDRB |= 0x07; /* for test */
PORTB =0x07;
}

void main(void)
{
IoInit();

SetupPITimer();

EnablePIT0();
EnablePIT1();
EnablePIT2();

asm CLI;

for(;;)
{

}

}

#pragma CODE_SEG __NEAR_SEG NON_BANKED
/* interrupt handler for PIT 0 */
interrupt void ISR_PIT0 ()
{
//PITINTE &= not_bit0; /* disable this interrupt for channel 0 */

PITTF |= 0x01; /* clear the interrupt flag */

PORTB_PB0 = ~PORTB_PB0;

}

interrupt void ISR_PIT1 ()
{
//PITINTE &= not_bit0; /* disable this interrupt for channel 0 */

PITTF |= 0x02; /* clear the interrupt flag */

PORTB_PB1 = ~PORTB_PB1;

}

interrupt void ISR_PIT2 ()
{
//PITINTE &= not_bit0; /* disable this interrupt for channel 0 */

PITTF |= 0x04; /* clear the interrupt flag */

PORTB_PB2 = ~PORTB_PB2;

}

#pragma CODE_SEG DEFAULT

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