void timer_isr()

in Z88DK/Z180/port.c [254:283]

• 15 lines of code
• 1 McCabe index (conditional complexity)

void timer_isr(void) __preserves_regs(a,b,c,d,e,h,l,iyh,iyl) __naked
{
#if configUSE_PREEMPTION == 1
    /*
     * Tick ISR for preemptive scheduler.  We can use a naked attribute as
     * the context is saved at the start of timer_isr().  The tick
     * count is incremented after the context is saved.
     *
     * Context switch function used by the tick.  This must be identical to
     * vPortYield() from the call to vTaskSwitchContext() onwards.  The only
     * difference from vPortYield() is the tick count is incremented as the
     * call comes from the tick ISR.
     */
    portSAVE_CONTEXT_IN_ISR();
    configRESET_TIMER_INTERRUPT();
    xTaskIncrementTick();
    vTaskSwitchContext();
    portRESTORE_CONTEXT_IN_ISR();
#else
    /*
     * Tick ISR for the cooperative scheduler.  All this does is increment the
     * tick count.  We don't need to switch context, this can only be done by
     * manual calls to taskYIELD();
     */
    portSAVE_CONTEXT_IN_ISR();
    configRESET_TIMER_INTERRUPT();
    xTaskIncrementTick();
    portRESTORE_CONTEXT_IN_ISR();
#endif
} // configUSE_PREEMPTION