• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 29 subscribers
  • Views 727 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

RM48 ADC Calibration & Mid-Point Calibration example Code.

HanSeoung Lyoo
Intellectual 320 points

Hello, TI.

I used to RM48 HDK.

I measured the voltage using ADC Module results are summarized as follows.

                              Voltage               Conversion Result

                              0V           ->                 0

                              1V           ->           about 790

                              2V           ->           about 1610

                              3V           ->           about 2389

                              4V           ->           about 3123

                              5V           ->               4095

condition: VREFHI : 5V, VREFLO : 0V 

So, I read the TRM.

Can i get the Calibration Error & Mid-Point Calibration Example Code ?

 

Thank you, I wait for TI's Reply.

 

 

  • 0
    TI__Mastermind 49120 points

    Hello,

    The RM48 technical reference manual clearly describes the steps to be followed for calibrating the ADC. Please refer to section 18.8.1.2 on page 821.

    The calibration mode allows you to choose four different reference voltages for conversion by the ADC. These are - VREFLO (conversion result = 0), VREFHI (conversion result = 0xFFF), and two other voltages below and above the mid-point. You can use the errors calculated from these four conversions to calculate the error correction to be applied to all conversions.

    We do not have a code example for this routine at this time.

    Regards, Sunil

  • 0 in reply to Sunil Oak
    Intellectual 320 points

    Thank you for your reply.

    What i want is as follows.

                    RM48 Conditions : VREFHI: 5V, VREFLO : 0V.

                    The AD1IN[x] INPUT : 0V, 1V, 2V, 3V, 4V, 5V is converted for each of 0x000, 0x333, 0x666, 0x999, 0xCCC, 0xFFF.

                    [x] is channel number.

    possible or impossible ?

     

    I want to your reply.

     

  • 0 in reply to HanSeoung Lyoo
    TI__Mastermind 49120 points

    There are no internal voltage dividers that allow you to generate these different voltages on an input channel. The only reference voltages that can be internally generated are the four levels created using the VREFHI and VREFLO supplies.

    Regards, Sunil