#define OUTPUTB         PORT1.1
#define OUTPUTC         PORT1.2

const uint8_t port_val[] = {0x02, 0x03};

void func(void)
{
    bool B_or_C;
    
    SETUP_TIMER();
    START_TIMER();  // Output A goes high 2 clock cycles after this instruction.
}

//---------------------------------
// ISR to drive output B or C high.
// Note that this is deterministic code and must not have any conditional statements!
//---------------------------------
void _interrupt[TIMER] drive_B_or_C_high(void)
{
    PORTA = PORTA | port_val[BorC];
}