CSC_Pr_RxMesaj

#include <c8051F040.h>  // declaratii SFR
#include <uart1.h>
#include <Protocol.h>
#include <UserIO.h>

extern nod retea[];                     // reteaua Master-Slave, cu 5 noduri

extern unsigned char STARE_NOD;     // starea initiala a nodului curent
extern unsigned char TIP_NOD;           // tip nod
extern unsigned char ADR_MASTER;    // adresa nodului master

extern unsigned char timeout;       // variabila globala care indica expirare timp de asteptare eveniment
//***********************************************************************************************************
unsigned char RxMesaj(unsigned char i);             // primire mesaj de la nodul i
unsigned char ascii2bin(unsigned char *ptr);                    // functie de conversie 2 caractere ASCII HEX in binar

//***********************************************************************************************************
unsigned char RxMesaj(unsigned char i){                 // receptie mesaj
    unsigned char j, ch, sc, adresa_hw_dest, adresa_hw_src, screc, src, dest, lng, tipmes, *ptr;
    if (ADR_NOD == MASTER)      // Daca nodul este master...
    {
        ch = UART1_Getch_TMO(1000);     // M: asteapta cu timeout primul caracter al raspunsului de la slave
        if (timeout)
        {
            return TMO;             // M: timeout, terminare receptie
        }
        else
        {
            retea[i].full = 0;  // M: raspunsul de la slave vine, considera ca mesajul anterior a fost transmis cu succes
            if (ch != ADR_NOD)
            {
                do
                    ch = UART1_Getch_TMO(5);                        // M: ignora restul mesajului
                while (!timeout);
                return ERA;
            }
            else
            {
                screc = ADR_NOD;
                adresa_hw_src = UART1_Getch_TMO(5);

                if (timeout)
                    return CAN;
                screc ^= adresa_hw_src;

                if (ADR_NOD == SLAVE)
                    ADR_MASTER = adresa_hw_src;

                tipmes = UART1_Getch_TMO(5);

                if (timeout)
                    return CAN;

                if (tipmes >= 2) {
                    do
                        ch = UART1_Getch_TMO(5);                        // M: ignora restul mesajului
                    while (!timeout);
                    return TIP;
                }

                screc ^= tipmes;

                if (tipmes == USER_MES) {
                    src = UART1_Getch_TMO(5);

                    if (timeout)
                        return CAN;
                    screc ^= src;
                    dest = UART1_Getch_TMO(5);

                    if (timeout)
                        return CAN;
                    screc ^= dest;

                    if (ADR_NOD == MASTER) {
                        if (retea[dest].full == 1) {
                            do
                                ch = UART1_Getch_TMO(5);                        // M: ignora restul mesajului
                            while (!timeout);
                            return OVR;
                        }
                    }

                    lng = UART1_Getch_TMO(5);

                    if (timeout)
                        return CAN;

                    screc ^= lng;

                    if (ADR_NOD == MASTER){
                        retea[dest].bufbin.adresa_hw_src = adresa_hw_src;
                        retea[dest].bufbin.tipmes = tipmes;
                        retea[dest].bufbin.src = src;
                        retea[dest].bufbin.dest = dest;
                        retea[dest].bufbin.lng = lng ;

                        lng = UART1_Getch_TMO(5);

                        if (timeout)
                            return CAN;

                        screc ^= lng;

                        sc = UART1_Getch_TMO(5);

                        if (timeout)
                            return CAN;

                        if (sc == screc) {
                            retea[dest].full = 1;
                            return ROK;
                        }
                        else
                            return ESC;
                    }
                    else{
                        retea[ADR_NOD].bufbin.src = src;
                        retea[ADR_NOD].bufbin.lng = lng;

                        lng = UART1_Getch_TMO(5);

                        if (timeout)
                            return CAN;

                        screc ^= lng;

                        sc = UART1_Getch_TMO(5);

                        if (timeout)
                            return CAN;

                        if (sc == screc){
                            retea[ADR_NOD].full = 1;
                            return ROK;
                        }
                        else
                            return ESC;
                    }
                }
                else{
                    sc = UART1_Getch_TMO(5);
                    if (timeout)
                        return CAN;

                    if (sc == screc)
                        return ROK;
                    else
                        return ESC;
                }
            }
        }
    }
    else
    {
        do {
            do
                ch = UART1_Getch_TMO(5);                        // M: ignora restul mesajului
            while (!timeout);

            ch = UART1_Getch_TMO(2000 + ADR_NOD * 1000);

            if (timeout)
                return TMO;

        }
        while (ch != ADR_NOD);
        screc = ADR_NOD;
        adresa_hw_src = UART1_Getch_TMO(5);

        if (timeout)
            return CAN;
        screc ^= adresa_hw_src;

        if (ADR_NOD == SLAVE)
            ADR_MASTER = adresa_hw_src;

        tipmes = UART1_Getch_TMO(5);

        if (timeout)
            return CAN;

        if (tipmes >= 2) {
            do
                ch = UART1_Getch_TMO(5);                        // M: ignora restul mesajului
            while (!timeout);
            return TIP;
        }

        screc ^= tipmes;

        if (tipmes == USER_MES) {
            src = UART1_Getch_TMO(5);

            if (timeout)
                return CAN;
            screc ^= src;
            dest = UART1_Getch_TMO(5);

            if (timeout)
                return CAN;
            screc ^= dest;

            if (ADR_NOD == MASTER) {
                if (retea[dest].full == 1) {
                    do
                        ch = UART1_Getch_TMO(5);                        // M: ignora restul mesajului
                    while (!timeout);
                    return OVR;
                }
            }

            lng = UART1_Getch_TMO(5);

            if (timeout)
                return CAN;

            screc ^= lng;

            if (ADR_NOD == MASTER){
                retea[dest].bufbin.adresa_hw_src = adresa_hw_src;
                retea[dest].bufbin.tipmes = tipmes;
                retea[dest].bufbin.src = src;
                retea[dest].bufbin.dest = dest;
                retea[dest].bufbin.lng = lng ;

                lng = UART1_Getch_TMO(5);

                if (timeout)
                    return CAN;

                screc ^= lng;

                sc = UART1_Getch_TMO(5);

                if (timeout)
                    return CAN;

                if (sc == screc) {
                    retea[dest].full = 1;
                    return ROK;
                }
                else
                    return ESC;
            }
            else{
                retea[ADR_NOD].bufbin.src = src;
                retea[ADR_NOD].bufbin.lng = lng;

                lng = UART1_Getch_TMO(5);

                if (timeout)
                    return CAN;

                screc ^= lng;

                sc = UART1_Getch_TMO(5);

                if (timeout)
                    return CAN;

                if (sc == screc){
                    retea[ADR_NOD].full = 1;
                    return ROK;
                }
                else
                    return ESC;
            }
        }
        else{
            sc = UART1_Getch_TMO(5);
            if (timeout)
                return CAN;

            if (sc == screc)
                return ROK;
            else
                return ESC;
        }
    }
}


//***********************************************************************************************************
unsigned char ascii2bin(unsigned char *ptr){            // converteste doua caractere ASCII HEX de la adresa ptr
    unsigned char bin;

    if(*ptr > '9') bin = (*ptr++ - 'A' + 10) << 4;  // contributia primului caracter daca este litera
    else bin = (*ptr++ - '0') << 4;                                 // contributia primului caracter daca este cifra
    if(*ptr > '9') bin  += (*ptr++ - 'A' + 10);         // contributia celui de-al doilea caracter daca este litera
    else bin += (*ptr++ - '0');                                         // contributia celui de-al doilea caracter daca este cifra
    return bin;
}