• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 46 subscribers
  • Views 167 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.

ADS131M02: Reset seems to be occuring at a 0.51Hz frequnecy

Henry Juhanson
Prodigy 10 points
Part Number: ADS131M02

We have the mikroe adc 15 board for testing and after setting everything up I started noticting only the irst readings were valid.
After ~1.96seconds the board resets and we get 0xFF22 indicating a succesful reset.

This seems to be also happening even if I dont configure any registers.
I leave everything at default, send NULL in a loop every 100ms and still get a a 0xFF22 at the same frequency.

With configuring adc:

configured adc wiht reset after 1.9s

Currently dont have a picture without conifiguring it, will upload it later if necessary,
but in that case the first response from the ADC is 0xFF22,
subsequent responses are 0x500 until the next drdy signal after which I get one 0xFF22 once again.

Is it possible the adc is faulty?

  • +1
    TI__Mastermind 18900 points

    Hello Henry,

    A couple of things before I start diving into the response. I'm gong to assume "reset" is the SYNC/RESET pin, which is an active low pin. Is the first small toggle of RESET an attempt to Synchronize? If it is not, I would look into the signal integrity of the digital communication lines with an oscilloscope. When I see small bouncing on the pin, sometimes this indicates a grounding issue that is so bad that it's picked up by the logic analyzer

    In addition, holding RESET low for that long would keep the device in reset. Is this intended? I would assume the device would not work as well stuck in the RESET state.

     

    Assuming 0xFF22 for the response STATUS of a NULL command, I would not say this indicates a successful reset. 0x0500 would indicate a successful RESET as those are the defaults. 0xFF22 shows the the SPI interface is LOCKED, there's CRC errors, and the word length is no longer the default of 24 bits. This almost sounds like an error with the SPI frame, but I don't want to get into these details before we discuss the specifics of RESET and what you intend to do.

    Thanks,

    -Cole

  • 0 in reply to Cole Macias
    Prodigy 10 points

    It was the reset pin. I had toggled it 3 times in the initialization phase and had completly missed it. 

    Thanks.