localtimep.nc

tinyos2.0版本驱动

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module LocalTimeP {
    provides {  
        interface LocalTime<T32khz> as LocalTime32kHz;
        interface WideLocalTime<T32khz> as WideLocalTime;
    }
    uses {
        interface Counter<T32khz,uint16_t> as Counter32khz16;
    }
}
implementation  {
    typedef union 
    {
        int64_t op;
        struct {
            uint32_t lo;
            int32_t hi;
        };
    } i64parts_t;
    
    uint16_t counter2sec = 126;
    int32_t dayCounter = 0;
    bool increaseDay = FALSE;
    async command uint32_t LocalTime32kHz.get() {
        uint32_t time;
        unsigned t;
        bool dirty1;
        bool dirty2;
        atomic {
            increaseDay = FALSE;
            do {
                dirty1 = call Counter32khz16.isOverflowPending();
                t = call Counter32khz16.get();
                dirty2 = call Counter32khz16.isOverflowPending();
            } while (dirty1 != dirty2);
            time = counter2sec;
            if(dirty1) {
                ++time;
                if(time == 0) {
                    increaseDay = TRUE;
                }
            }
            time = (time << 16) + t;
        }
        return time;
    }

    async command int64_t WideLocalTime.get() {
        i64parts_t time;
        uint32_t t;
        atomic {
            t = call LocalTime32kHz.get();
            time.hi = dayCounter;
            if(increaseDay) time.hi++;
            if(time.hi < 0) time.hi = 0;
            time.lo = t;
        }
        return time.op;
    }
    
    async event void Counter32khz16.overflow() {
        ++counter2sec;
        if(counter2sec == 0) ++dayCounter;
        if(dayCounter < 0) dayCounter = 0;
    }
}