MCP4725 on my PI3 it seems does not work

stetodaro
2018-09-09
2022-11-25
  • stetodaro - 2018-09-09

    Hi All,

    Can anyone help me?

    I installed the MCP4725 library found here on the forum in the dedicated section.

    Everything seems connected and configured correctly:

    • Executing ic2detect I see correctly 61 as I setteded on the chip
    • In my codesys application it's all green and on run.
    • I can handle other TDA8444 DACs but the MCP4725 has a 2.6v fixed output for any value I write in
      MCP4725.xdacIn

    Thank you for your attention
    Bye

    IMG: Bild

     
  • stetodaro - 2018-09-09

    Solved!

    61 is on HEX format. On Codesys must be wrote in UINT

    61HEX = 97UINT

     
  • princessdvlk - 2022-11-25

    Hi!

    I am facing a similar problem like you. I have downloaded the MCP4725 library from this forum. No matter what value I put in the MCP4725.xdacIn, the voltage is always at 0V.

    iDacValue : INT;
    MCP4725.xdacIn := iDacValue; (screenshot = Issue DAC 1)

    I am using a hardware that has raspberry pi core. The Codesys version I am using is Ver3.5 SP17 Patch3. I tried putting 97 in I2C Bus Parameters for MCP4725 (screenshot = Issue DAC 2) but still I am facing the same issue.

    I have been using ADC in I2C mode as well. I didn't face any problem with that as I got an example code for it. Could this be because I am using ADC and DAC with I2C at the same time?

    Could you please help me out? I am attaching the screenshots as well. It is also mentioned in the library method file 'AfterReadInputs' (screenshot = Issue DAC 3) that we must change wInfo[0] to 16#60 from 16#40 if we want to write the values into DAC register and EEPROM. I guess these files are write protected. Do I have to change this value and if so how? I am unable to do that.

    Looking forward to your reply.

    Thanking you in advance.
    Best Regards!

     

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