用MCU自带的IIC模块程序，不知有错否。SCL波形都没产生。

只看该作者 · 2007-12-10 15:54

void IICInit(void) {
/* ### Init_IIC init code */
/* IICF: MULT1=0,MULT0=1,ICR5=0,ICR4=0,ICR3=0,ICR2=0,ICR1=0,ICR0=0 */
  IICF = 0x40;
  /* IICA: ADDR7=0,ADDR6=0,ADDR5=0,ADDR4=0,ADDR3=0,ADDR2=0,ADDR1=0 */
  IICA = 0x00;
  /* IICS: TCF=0,IAAS=0,BUSY=0,ARBL=1,SRW=0,IICIF=1,RXAK=0 */
  IICS = 0x12;                         /* Clear the interrupt flags */
  /* IICC: IICEN=1 */
  IICC |= (unsigned char)0x80;
  /* IICC: IICEN=1,IICIE=0,MST=0,TX=1,TXAK=0,RSTA=0 */
  IICC = 0x90;
}

void IICWriteByte(word adr, byte dt){
    word temp;
    gAdr=adr;

    temp = (gAdrH & 0x01) << 1; //get A8 of 24c04 address.
    IICC_TXAK=0;
    IICC|=0x30;            //MST=1 TX=1  and generate START condition
    IICD =IIC_SLAVE_ADR|temp;
    while(!IICS_IICIF);    //wait untill TX completed
    IICS_IICIF=1;          //clear IICIF
    while(IICS_RXAK);      //check for slave ack

    IICD = gAdrL;
    while(!IICS_IICIF);
    IICS_IICIF=1;
    while(IICS_RXAK);

    IICD=dt;
    while(!IICS_IICIF);
    IICS_IICIF=1;
    while(IICS_RXAK);

    IICS_IICIF=1;
    IICC_MST=0;
}

void IICWriteN(word adr,byte *dt,byte n){

    byte i;
    for(i=0;i<n;++i) {
      IICWriteByte(adr+i,dt);
    }
}

byte IICReadByte(word adr){

    word temp;
    byte d;

    gAdr=adr;
    temp = (gAdrH&0x01)<<1;     //get A8 of 24c04 address.
    IICC_TXAK=0;
    IICC|=0x30;            //MST=1 TX=1  and generate START condition
    IICD =IIC_SLAVE_ADR|temp;
    while(!IICS_IICIF);    //wait untill TX completed
    IICS_IICIF=1;          //clear IICIF
    while(IICS_RXAK);      //check for slave ack

    IICD = gAdrL;
    while(!IICS_IICIF);
    IICS_IICIF=1;
    while(IICS_RXAK);

    IICS_IICIF=1;
    IICC_RSTA=1;

    IICD =IIC_SLAVE_ADR|temp;
    while(!IICS_IICIF);    //wait untill TX completed
    IICS_IICIF=1;          //clear IICIF
    while(IICS_RXAK);      //check for slave ack

    IICC_TX=0;
    IICC_TXAK=1;
    d=IICD;                //dummy read
    while(!IICS_IICIF);
    IICS_IICIF=1;
    IICC_MST=0;
    d=IICD;
    return d;
}

byte* IICReadN(word adr,byte n){
    word temp;
    byte i,d;
    static byte * dt;

    gAdr=adr;
    temp = (gAdrH&0x01)<<1;     //get A8 of 24c04 address.
    IICC_TXAK=0;
    IICC|=0x30;            //MST=1 TX=1  and generate START condition
    IICD =IIC_SLAVE_ADR|temp;
    while(!IICS_IICIF);    //wait untill TX completed
    IICS_IICIF=1;          //clear IICIF
    while(IICS_RXAK);      //check for slave ack

    IICD = gAdrL;
    while(!IICS_IICIF);
    IICS_IICIF=1;
    while(IICS_RXAK);

    IICS_IICIF=1;
    IICC_RSTA=1;

    IICD =IIC_SLAVE_ADR|temp|1;
    while(!IICS_IICIF);    //wait untill TX completed
    IICS_IICIF=1;          //clear IICIF
    while(IICS_RXAK);      //check for slave ack

    IICC_TX=0;
    //IIC_TXAK=1;
    d=IICD;                //dummy read
    while(!IICS_IICIF);
    IICS_IICIF=1;

    for(i=0;i<(n-1);++i){

         dt=IICD;
         while(!IICS_IICIF);
         IICS_IICIF=1;
    }
    IICC_TXAK=1;
    dt=IICD;
    while(!IICS_IICIF);
    IICC_MST=0;
    return dt;
}