AnsweredAssumed Answered

BF533 EZ KIT Talkthrough Example

Question asked by ridwanoz on Jul 10, 2012
Latest reply on Jul 12, 2012 by ridwanoz

Hi,

 

I was studying on the talkthrogh example of adsp bf533 in the example folder of visualdsp++ 5.0 and i changed some code parts.

Here is the original ISR.c :

 

EX_INTERRUPT_HANDLER(Sport0_RX_ISR)

{

// confirm interrupt handling

*pDMA1_IRQ_STATUS = 0x0001;

 

 

// copy input data from dma input buffer into variables

iChannel0LeftIn = iRxBuffer1[INTERNAL_ADC_L0];

iChannel0RightIn = iRxBuffer1[INTERNAL_ADC_R0];

iChannel1LeftIn = iRxBuffer1[INTERNAL_ADC_L1];

iChannel1RightIn = iRxBuffer1[INTERNAL_ADC_R1];

 

// call function that contains user code

Process_Data();

 

 

// copy processed data from variables into dma output buffer

iTxBuffer1[INTERNAL_DAC_L0] = iChannel0LeftOut;

iTxBuffer1[INTERNAL_DAC_R0] = iChannel0RightOut;

iTxBuffer1[INTERNAL_DAC_L1] = iChannel1LeftOut;

iTxBuffer1[INTERNAL_DAC_R1] = iChannel1RightOut;

}

 

 

after changed:

 

 

EX_INTERRUPT_HANDLER(Sport0_RX_ISR)

{

// confirm interrupt handling

*pDMA1_IRQ_STATUS = 0x0001;

 

 

// copy input data from dma input buffer into variables

iChannel0LeftIn = iRxBuffer1[INTERNAL_ADC_L0];

iChannel0RightIn = iRxBuffer1[INTERNAL_ADC_R0];

iChannel1LeftIn = iRxBuffer1[INTERNAL_ADC_L1];

iChannel1RightIn = iRxBuffer1[INTERNAL_ADC_R1];

 

// call function that contains user code

Process_Data();

 

 

// copy processed data from variables into dma output buffer

iTxBuffer1[INTERNAL_DAC_L0] = iChannel0LeftOut/2;

iTxBuffer1[INTERNAL_DAC_R0] = iChannel0RightOut;

iTxBuffer1[INTERNAL_DAC_L1] = iChannel1LeftOut;

iTxBuffer1[INTERNAL_DAC_R1] = iChannel1RightOut;

}

 

when i give the input signal, i observe that the left out channel is an irrelevant square like signal.

 

What i want to do is reducing the amplitude of the input signal on the left channel while transferring it to the output.

 

How can i fix this?

 

and i also tried that ........iTxBuffer1[INTERNAL_DAC_L0] = 7000000;......... in order to get a flat signal. this also did not work.

 

 

Waiting for help

 

thx in advance

Outcomes