DLP2010EVM-LC: DLP® products forum

Part Number: DLP2010EVM-LC

I am attempting to read data from a 2010 EVM and am getting unexpected results from my read functions.  This function is very
similar to my write functions (all of which work no problem).  Can anyone give a suggestion as to what I might be getting wrong?
This function should return the 'input source selection' detailed at the bottom of this message.

int DLPC3470_USB_Read()
{
   UINT8 gpioValue = 0;
   UCHAR rData[64];
   CY_DATA_BUFFER rdBuffer;
   CY_I2C_DATA_CONFIG i2cReadConfig;
   CY_RETURN_STATUS retStatus;
   int retry = 1000;
   UINT32 timeout = 5000;

   memset(rData, 0, sizeof(rData));
   rdBuffer.buffer = rData;
   rdBuffer.buffer[0] = 0x06;        // read input source select 
   rdBuffer.length = 1;
   i2cReadConfig.slaveAddress = 0x1B;
   i2cReadConfig.isNakBit = false;
   i2cReadConfig.isStopBit = true;

   if (cyHandle == NULL)             // cyHandle is static to the file and is open at this point
      return CY_ERROR_INVALID_HANDLE;

   // set GPIO5 to request I2C bus; wait for GPIO6 to go high to awknowlege request; set GPIO9 high to enable I2C bus
   retStatus = CySetGpioValue(cyHandle, 0x05, 0x01);
   while (gpioValue != 1 && retry--)
	   retStatus = CyGetGpioValue(cyHandle, 0x06, &gpioValue);
   retStatus = CySetGpioValue(cyHandle, 0x09, 0x01);

   // after this call, I would expect rdBuffer.buffer[0] to hold the current source select....it does not
   printf("rdBuffer values before CyI2cRead() call\n");
   printf("rdBuffer[0] is %d\nrdBuffer[1] is %d\nrdBuffer[2] is %d\n", rdBuffer.buffer[0], rdBuffer.buffer[1], rdBuffer.buffer[2]);
   retStatus = CyI2cRead(cyHandle, &i2cReadConfig, &rdBuffer, 5000);
   if (retStatus != CY_SUCCESS)
	   printf("CyI2cRead failure\n");
   else
   {
	   printf("Results of CyI2cRead()\n");
	   printf("rdBuffer should now have a value of 0-5 or 255 per section 3.1.2 of DLPC3470 and DLP3478 Software Programmer's Guide\n");
	   printf("rdBuffer[0] is %d\nrdBuffer[1] is %d\nrdBuffer[2] is %d\n", rdBuffer.buffer[0], rdBuffer.buffer[1], rdBuffer.buffer[2]);
   }

   retStatus = CySetGpioValue(cyHandle, 0x05, 0x00);   // done with I2C bus
   retStatus = CySetGpioValue(cyHandle, 0x09, 0x00);   // done with I2C bus
   return rdBuffer.transferCount;
}

--------------------- output here ------------------------

rdBuffer values before CyI2cRead() call
rdBuffer[0] is 6
rdBuffer[1] is 0
rdBuffer[2] is 0
Results of CyI2cRead()
rdBuffer should now have a value of 0-5 or 255 per section 3.1.2 of DLPC3470 and DLP3478 Software Programmer's Guide
rdBuffer[0] is 158
rdBuffer[1] is 0
rdBuffer[2] is 0

-------------------- expected results ---------------------

3.1.2 Read Input Source Select (06h)

This command reads the operating mode of the system.

3.1.2.1 Read Parameters

This command has no parameters.

3.1.2.2 Return Parameters

Byte 1 Operating Mode
00h Display - External Video Mode
01h Display - Test Pattern Generator Mode
02h Display - Splash Screen Mode
03h Light Control – External Pattern Streaming Mode
04h Light Control – Internal Pattern Streaming Mode
05h Light Control – Splash Pattern Mode
06h - FEh Reserved
FFh Standby Mode

This command works in all operating modes and has no effect on the current system configuration.