• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 82 subscribers
  • Views 423 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS320F28075: ADC not working properly - TMS320F28075

sandeep chavan
Intellectual 470 points
Part Number: TMS320F28075

Hello,

Currently we are working ADC of TMS320F28075 , For testing ADC functionality i have used two different reference codes from TI.

1. ADC SOC using PWM 

2. ADC SOC using force software start

we have used custom designed board to test this functionality . while testing both example codes we observed that ADC result resistors contains 0 value after every conversation.

Means no data is getting captured on ADC result resistor.

So i prepared separate example code referring software force start method and used 4 channels of ADCa. 

In this example code if we force start ADC conversion after every 1 msec then we are not getting any data in result resistors, but if we force start adc conversion after 40 or 50 msec then we get values in ADC result resistor. why this is happening.

ADCCLK = SYSCLK / 4 = 120MHz/4 = 30MHz

ACQPS = 120

above configuration we have used for ADC.  

Can anyone guide in this. We have to capture 10 ADC channels data in 1 msec. 

  • 0
    TI__Guru 53165 points
    So you're using the software force to start the conversions? Are you triggering all 10 conversions at the same time? Are you checking an interrupt flag to confirm that the conversion is completing?

    Have you tried different values of the ADCCLK prescale or ACQPS? Your prescaler could be smaller--the max ADCCLK is 50Mhz, so you could use 2.5 although this isn't necessarily the problem. How did you arrive at an ACQPS of 120?

    Whitney
  • 0 in reply to Whitney Dewey
    Intellectual 470 points
    Hello Whitney,

    Thanks for quick response. This issue is resolved now. I made mistake while interrupt initialization

    Sandeep