Another problem with I2C module in DM642

Hi,

 

I have another problem with I2C in DM642. The following is my code:

 

I2C_Handle hI2c;

I2C_Config i2cCfg;

com_init();
 
CHIP_config( &chipConfig );     //enable I2C module in PERCFG register

hI2c = I2C_open(I2C_DEV0, I2C_OPEN_RESET);

if ( hI2c != INV )
{   
     I2C_config(hI2c, &mycfgData);                 //Configure the I2C module
     I2C_FSETH(hI2c, I2CMDR, IRS, 1);              //enable the I2C module
   
     if (!I2C_bb(hI2c))                                                                 //busy?
     { 
          I2C_start(hI2c);                                              //set the STT bit   
          I2C_writeByte(hI2c, 0x90);                   //write the slave address
       
          while( !I2C_FGETH(hI2c,I2CSTR,NACK) )  //receive ACK signal
          {
              puts("success!");      //succeeding transfer the slave address
              I2C_sendStop(hI2c);                         //generate STOP signal
          }

          I2C_sendStop(hI2c);
          I2C_close(hI2c);                                        //Close I2C0 Module

 

Strangely, after executing "I2C_start(hI2c)", I only can see the SCL turne to be low, while the SDA remains high. Furthermore, there is no clock signal on the SCL line and no ACK from the receiver.

 

Is there anything that I should do to initiate the I2C module? or there is some problem with my I2C module or DSP?

 

Thank you very much!

Victorwang
V...@yahoo.com.cn
2005-09-26