I2C read using CSL

Hi,I'm using C6472, CCS3.3, and I would like to write a simple I2C read routine.

I tried the example code that came with the CSL library and it worked fine (write and read back in loopback mode).

I need a simple read. I tried to modify the example code with no success. I tried other examples from the web with no success either.

Here is partial code. I removed many of the status return checks to simplify the reading.

My problem is that the read register (RRDY bit) is never ready! Do I have to start by  transmitting the slave address, or its is sent automatically? Please help.

void I2C_init(void) {

    CSL_Status         status;
    CSL_I2cObj      i2cObj;
    CSL_I2cHwSetup  hwSetup;

    hwSetup.mode           = CSL_I2C_MODE_MASTER;
    hwSetup.dir            = CSL_I2C_DIR_TRANSMIT;
    hwSetup.addrMode       = CSL_I2C_ADDRSZ_SEVEN;        //7bits addressing mode
    hwSetup.sttbyteen      = CSL_I2C_STB_DISABLE;        //DISABLE == disable start byte (Normal mode)
    hwSetup.ownaddr        = CSL_I2C_SLAVE_ADDR;        //address used to talk to this DSP chip
    hwSetup.ackMode        = CSL_I2C_ACK_ENABLE;
    hwSetup.runMode        = CSL_I2C_FREE_MODE_DISABLE;    //DISABLE == stop at breakpoint
    hwSetup.repeatMode     = CSL_I2C_REPEAT_MODE_DISABLE;//DISABLE == no repeat mode
    hwSetup.loopBackMode   = CSL_I2C_DLB_DISABLE;        //DISABLE == digital loopback mode is disabled
    hwSetup.freeDataFormat = CSL_I2C_FDF_DISABLE;        //DISABLE == use 7/10bits addressing mode
    hwSetup.resetMode      = CSL_I2C_IRS_ENABLE;         //ENABLE  == put in reset
    hwSetup.bcm            = CSL_I2C_BCM_DISABLE;        //DISABLE == disable back compatibility
    hwSetup.inten          = 0x00;                       //interrupt enable mask
    hwSetup.clksetup       = &clksetup;                    //prescaler and clock setup

    CSL_i2cInit(NULL);
    sI2C_Handle = CSL_i2cOpen(&i2cObj, CSL_I2C, NULL, &status);
    CSL_i2cHwSetup(sI2C_Handle, &hwSetup);
    CSL_i2cHwControl(sI2C_Handle, CSL_I2C_CMD_OUTOFRESET, NULL);
}

uint16_t I2C_read(uint16_t endPoint, uint8_t *data_p, uint16_t length) {
    
     int16_t timecount, timeout = 0x1000;
    CSL_Status status = CSL_SOK;       
    uint16_t response;   
    uint32_t BbResponse;    //busy bit
    uint32_t cmd_arg;   
    uint8_t  endPointAddress;

    // set address of the slave device
    endPointAddress == 0x40;
    CSL_i2cHwControl(sI2C_Handle, CSL_I2C_CMD_SET_SLAVE_ADDR, &endPointAddress);   
    CSL_i2cHwControl(sI2C_Handle, CSL_I2C_CMD_SET_DATA_COUNT,&length);   
  
    // Configure Options for Receiving - Master Reciever mode
//  CSL_i2cHwControl(sI2C_Handle, CSL_I2C_MODE_MASTER,NULL); //master
    CSL_i2cHwControl(sI2C_Handle, CSL_I2C_CMD_DIR_RECEIVE,NULL); //receive
    CSL_i2cHwControl(sI2C_Handle, CSL_I2C_CMD_ENABLE,NULL); //enable
    CSL_i2cHwControl(sI2C_Handle, CSL_I2C_CMD_START,NULL);   //start

    // Wait for the transfer to start
    do {
        CSL_i2cGetBusBusy(sI2C_Handle,&BbResponse);
    } while(BbResponse != 1);
   
    while(length) {     //receive all data words
        CSL_i2cGetHwStatus(sI2C_Handle, CSL_I2C_QUERY_NACKSNT, &response);    //check NACK
        if ( response != 0x0001 ) {   

            CSL_i2cGetHwStatus(sI2C_Handle, CSL_I2C_QUERY_ACS_RDY, &response);   //check ARDY
            if (response != CSL_I2C_ACS_READY ) { //we still have more data to read

               CSL_i2cGetHwStatus(sI2C_Handle, CSL_I2C_QUERY_RX_RDY, &response);   //check RRDY (can't get past this point)
                if ( response == CSL_I2C_RX_READY ) {   
                    CSL_i2cRead(sI2C_Handle,data_p++);  //Read Data
                    length --;   
   
                    // Clear Receive Ready field
                    do{
                        cmd_arg=CSL_I2C_CLEAR_RRDY;   
                        CSL_i2cHwControl(sI2C_Handle,CSL_I2C_CMD_CLEAR_STATUS,&cmd_arg);   
                        CSL_i2cGetHwStatus(sI2C_Handle, CSL_I2C_QUERY_RX_RDY, &response);
                    }while(response==CSL_I2C_RX_READY);   
                }//if Rx ready   
            }//if ARDY: we still have data to read
   
            // Check for Arbitration Lost
            CSL_i2cGetHwStatus(sI2C_Handle,CSL_I2C_QUERY_AL, &response);   
            if ( response == CSL_I2C_ARBITRATION_LOST ) {  
                return 1001;   
            }
   
            /* Check for NACK */   
            CSL_i2cGetHwStatus(sI2C_Handle,CSL_I2C_QUERY_NACKSNT, &response);   
            if ( response == 0x0001 )   return 1002;   
  
            /* Check for Register Access Ready - Good Condition */   
            CSL_i2cGetHwStatus(sI2C_Handle,CSL_I2C_QUERY_ACS_RDY, &response);//why ARDY!=1?     
            if ( response == CSL_I2C_ACS_READY ) {   
                do{
                    cmd_arg=CSL_I2C_CLEAR_ARDY;   
                    CSL_i2cHwControl(sI2C_Handle,CSL_I2C_CMD_CLEAR_STATUS,&cmd_arg);   
                    CSL_i2cGetHwStatus(sI2C_Handle,CSL_I2C_QUERY_ACS_RDY, &response);
                }while(response == CSL_I2C_ACS_READY);   
                return 0;   
            }
        } // if NACK
    } //for all data

    // I2C Timeout
    return 2002;
}