ISR Question (update)

Follow up to a previous thread posted last week.

The issue is that my timer interrupt won't work if serial interrupts are enabled, unless the timer interrupt priority is set to high.

As per Erik's request here is the source code:

CKCON = 0x08; /T2/12, T1/12, T0/4, MOVX Stretch 2

Serial Port setup:

void SetSerialPorts(void)
{

SCON0 = 0x50;
PCON |= 0x80;

SCON1 = 0x50;
EICON |= 0x80;

//Set Timer 1 for Baud Generation
TMOD |= 0x20;
TH1  = 0xF8;    //19.2k  Baud @ 29.4912 MHz
TR1  = 1;       //Run Timer 1

TI_0 = 1;
TI_1 = 1;
RI_0 = 0;
RI_1 = 0;

}

Timer2 Initialization:

void InitTimer2(void)
{

timer_flags = 0;
timer_tick_count = 0;

T2CON = 0x00;

RCAP2H = (TIMER_COUNT >> 8);
RCAP2L = (TIMER_COUNT & 0x00FF );

PT2 = 1;  //Have to set high so it will trigger
ET2 = 1;

}

Serial ISR:

void Serial_isr(void) interrupt 4
{


if ( RI_0 )
   RI_0 = 0;

if ( RI_1 )
{

   rx_buffer[ rx_write_cnt++ ] = SBUF1;
   if ( rx_write_cnt == MAXCOM ) rx_write_cnt = 0;

   RI_1 = 0;

} //__if (RI_1)__

}

Timer2 ISR:

void Timer2_isr(void) interrupt 5
{

T2CON = 0x00;

timer_tick_count++;

if ( timer_tick_count%10 == 0 )  //10Hz clock
   tmr_sample_adc = 1;

if ( timer_tick_count%20 == 0 )  //5Hz clock
   tmr_update = 1;

if ( timer_tick_count%100 == 0 ) //1Hz clock
{

   tmr_seconds = 1;
   timer_tick_count = 0;

}

TR2 = 1;

}

Can anyone figure out what I've done wrong from this? If you need me to post any other part of the code please let me know.

Thanks,
Paul