PSoC™ 5, 3 & 1 Forum Discussions

I am new to Cypress, trying to get a UDB I2C master to work.  I have successfully fetched the device ID from my test I2c slave device, an ADXL345 accelerometer.  However I have two problems:

1) Most of the time, the address that the I2C master puts on the bus right after the start bit is to address 1.  With enough resets of the debugger, the I2C master will occasionally get the correct 0x53 address on the bus.  When that happens, the slave responds correctly and data makes it into my buffer, and all return values are zero.

2) Even if the address was correct in #1, the final stop bit of the 2nd cycle (the I2C read) will hang on this line in the I2C_MasterSendStop function: while(I2C_WAIT_STOP_COMPLETE(I2C_CSR_REG)).  I don't see the STOP bit on the scope either.  If I put in a breakpoint before the function and then single step, I see the STOP condition on the scope and it completes.

For #1, what do I need to do to get the I2C Master ready to go to work on the correct address all of the time?

For #2, do I need to check a flag before I call on the I2C_MasterSendStop function?

Complete project attached.  Code snippet from main follows:

    

#include <project.h>

    

uint8 buffer[10];
uint8 results[20];

    

void ReadRegs(void)
{
    uint8 i=0;
    
    results[i++] = I2C_MasterClearStatus();          // This was added but didn't help

    

    results[i++] = I2C_MasterSendStart( 0x53, 0 );  // start write

    

    results[i++] = I2C_MasterWriteByte( 0x0 );      // Register 0 

    

    //results[i++] = I2C_MasterSendStop();           // Commented out, switched to Restart but didn't matter

    

    results[i++] = I2C_MasterSendRestart( 0x53, 1 ); // Turnaround for next cycle
    
    buffer[0] = I2C_MasterReadByte( 1 );             // Read 1 byte

    

    results[i++] = I2C_MasterSendStop();             // stop - This never completes at full speed
    
    while (1)
    ;
}

    

int main()
{
    CyGlobalIntEnable; /* Enable global interrupts. */

    

    /* Place your initialization/startup code here (e.g. MyInst_Start()) */
    
    I2C_Start();

    

    ReadRegs();
}

   

I am using CY8C4124LQI-443 Psoc 4100 family in my project. I need to use emulated eeprom. There is an example in psoc. But I have problem when I use. I want to read the data written on eeprom after restart the system.

I use this command CY_GET_REG8(adress); or Data = (*((uint8 *) (adres)));. Data read is 0. 

What is the problem of this? Can anyone explain the detail of this? (I think after I close the system, Data written is deleted by the microcontroller.?)

Thanks for helping. 

Hello Everyone,

I have recently updated my psoc 3.3 to psoc 4 and then i checked my already working program in the posc creator 4  it not even working wt all  just it make the device turn off immediately i dont able understand  can anybody please tell me why this is happening do i need make any changes in the psoc creator 4 

any help would be greatly appreciated

Thank you

prabhu