I2C_read() with C5515 and AIC3204 using the CSL

Hi,

In order to read I2C register, you need to set I2C subaddress first with I2C write. For example, if you want read register 0x05, you write 0x05 and read contests.

 gI2cWrBuf[0]= 0x05;    // I2C subaddress

 status = I2C_write(gI2cWrBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);

 status = I2C_read(myread, 1, CSL_I2C_CODEC_ADDR,      TRUE, startStop, CSL_I2C_MAX_TIMEOUT, FALSE);

myread[0] is your read value.

Regards,

Hyun

Hello Hyum

Thanks for your reply. I tried a few things and here are my results:

(I have put the screenshots into this ZIP file.)

8105.i2c_5515_error.zip

1. Set breakpoints as shown in screenshot i2c_1.png

For each breakpoint I get the following data on my oscilloscope:

After breakpoint no.

   1  -  1_01.png  (I2C Write correct.)
   2  -  1_02.png  (I2C Write correct.)
   3  -  1_03.png  (Instead of a Master Write=0 it is 1, indicating a Read)
   4  -  1_04.png  (Now it it looks fine but rBuf[0]=0 )
   5  -  1_05.png  (Same again, but this time rBuf[0]=2 as expected.)

Here again is what I read from the codec:

   I2C_read() register data is: 0
   I2C_read() register data is: 0
   I2C_read() register data is: 2



2. Now I set the breakpoints as shown in screenshot i2c_2.png

   1  - 2_01.png  (I2C Write correct.)
   2  - 2_02.png  (I2C Write correct.)
   3  -  2_03.png  (Aha! Now there isn't the faulty Master Write=1)
   4  -  2_04.png  (OK, I get a rBuf[0]=2)
   5  -  2_05.png  (That's OK.)
   6  -  2_06.png  (Again I get the rBuf[0]=2)
   7  -  2_07.png  (OK)
   8  -  2_08.png  (OK, rBuf[0]=2)

And my Console tells the same:

   I2C_read() register data is: 2
   I2C_read() register data is: 2
   I2C_read() register data is: 2


3. If I set one breakpoint like in i2c_3.png or no breakpoint at all:


   I2C_read() register data is: 0
   I2C_read() register data is: 0
   I2C_read() register data is: 2



I tested it several times, with different pages, with a complete restart, new enumeration of the debugger, etc.


So, is this a problem with the debugger or the DSP itself? Will it work if I just flash it and let it run free?

Martin

Here is my code I used for this test:

#include <stdio.h>
#include <csl_general.h>
#include <csl_i2c.h>

/* I2C Configuration Details */
#define CSL_I2C_SYS_CLK            (100)    // In MHz    (System Clock after PLL)
#define CSL_I2C_BUS_FREQ        (10)    // In KHz
#define CSL_I2C_CODEC_ADDR        (0x18)    // Codec (AIC3204)     0011000 -> 7 bit
#define CSL_I2C_OWN_ADDR        (0x2F)

void wait( Uint32 delay )
{
    volatile Uint32 i;
    for ( i = 0 ; i < delay ; i++ ){ };
}

void delay( Uint32 usec )
{
    wait( (Uint32)usec * 8 );
}

CSL_Status        status;
CSL_I2cSetup    i2cSetup;
Uint16            startStop;

void main( void )
{
    Uint16 wBuf[2];        // Write Buffer
    Uint16 rBuf[1];        // Read Buffer

    /* Initialize I2C module */
    status = I2C_init(CSL_I2C0);
    if(status != CSL_SOK)
    {
        printf("I2C Init Failed!!\n");
    }

    /* Setup I2C module */
    i2cSetup.addrMode    = CSL_I2C_ADDR_7BIT;
    i2cSetup.bitCount    = CSL_I2C_BC_8BITS;
    i2cSetup.loopBack    = CSL_I2C_LOOPBACK_DISABLE;
    i2cSetup.freeMode    = CSL_I2C_FREEMODE_DISABLE;
    i2cSetup.repeatMode  = CSL_I2C_REPEATMODE_DISABLE;
    i2cSetup.ownAddr     = CSL_I2C_OWN_ADDR;
    i2cSetup.sysInputClk = CSL_I2C_SYS_CLK;
    i2cSetup.i2cBusFreq  = CSL_I2C_BUS_FREQ;
    startStop            = ( (CSL_I2C_START) | (CSL_I2C_STOP) );

    status = I2C_setup(&i2cSetup);
    if(status != CSL_SOK)
    {
        printf("I2C Setup Failed!!\n");
    }

    /* Test some codec register */

    // Codec SW Reset
    wBuf[0] = 0x0001;            // Codec Register Address
    wBuf[1] = 0x0001;            // Codec Register Data
    I2C_write(wBuf, 2, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);
    wait(20000);

    // Change Codec Page to 2
    wBuf[0] = 0x0000;
    wBuf[1] = 0x0002;
    I2C_write(wBuf, 2, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);
    delay(1800);
   
    // 1. Read current Codec Page
    wBuf[0] = 0x0000;
    rBuf[0] = 0x0000;
    I2C_write(wBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);
    I2C_read(rBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT, FALSE);
    printf("I2C_read() register data is: %d\n", rBuf[0]);
    delay(1800);   

    // 2: Read current Codec Page
    wBuf[0] = 0x0000;
    rBuf[0] = 0x0000;
    I2C_write(wBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);
    I2C_read(rBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT, FALSE);
    printf("I2C_read() register data is: %d\n", rBuf[0]);
    delay(1800);

    // 3: Read current Codec Page
    wBuf[0] = 0x0000;
    rBuf[0] = 0x0000;
    I2C_write(wBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);
    I2C_read(rBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, ( (CSL_I2C_START) | (CSL_I2C_STOP)), CSL_I2C_MAX_TIMEOUT, FALSE);
    printf("I2C_read() register data is: %d\n", rBuf[0]);
    delay(1800);
}

Hi,

You did a good job to find out. In fact, if you put the delay between I2C_write and I2C_read, it'll fix your problem.

    I2C_write(wBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, startStop, CSL_I2C_MAX_TIMEOUT);

   /* Give some delay */

   delay(1800); // It's the same effect of your break point.

    I2C_read(rBuf, 1, CSL_I2C_CODEC_ADDR, TRUE, ( (CSL_I2C_START) | (CSL_I2C_STOP)), CSL_I2C_MAX_TIMEOUT, FALSE);

Regards,

Hyun

Ah, right. Now this piece is working.

But still, this is not a valid REPEATED START condition! The example you suggest sends a STOP condition and after some delay a START condition. How can I achieve a REPEATED START condition with the CSL?

Hi,

We are looking into it now. I'll let you know when I get an answer.

Regards,

Hyun

Hi,

We have done with ccs_v3.3_examples\i2c\example2 csl_i2c_dma_example.c and modified it to use restart.

Please use attached file to check the restart working.

Regards,

Hyun