• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 46 subscribers
  • Views 786 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.

Verify ADS1298ECGFEPDK Power Setup / SPI trouble

Noel Teku
Intellectual 430 points

Hello,

I just ran my SPI code between my PIC and ADS1298ECGFEPDK, and in my buffer SPI2BUF (where the data should be) there was only  value '0x00'. I want to diagnose this first by, aside from ensuring my PIC code is okay, making sure my power setup is fine because I am only using the PIC to power it not the MMB0 board. Here are the following power connections that I've made:

PIC's 5 V - pin 10 of J4

PiC's 3.3V - pin 2 of JP24

PIC's ground - pin 5 of J4

Are these connections sufficient for powering the ADS1298ECGFEPDK on its own? Also, any suggestions on how to debug SPI? I'm already planning on using an oscilloscope to verify that the SPI signals from the PIC that I'm sending are valid.

Thanks,

Noel Teku

  • 0
    TI__Mastermind 38745 points
    Hey Noel,

    A great way to tell if the device is powered it so probe the DRDY pin to see if it is signalling that data is ready at the data rate. Alternatively, probing the VCAP2 pin (or perhaps the positive terminal of C2) should yield (AVDD + AVSS)/2.

    Probing the SPI lines with an oscilloscope or logic analyzer is by far the best method for debugging interface issues. In all of my experience, seeing the interface signals points to the issue in the code in one way or another.

    Regards,
    Brian Pisani
  • 0 in reply to Brian Pisani
    Intellectual 430 points
    Hi Brian,

    Thanks for the quick response! For probing the DRDY pin, would the procedure for that be essentially hooking up a male to male wire so that one lead connects to the DRDY pin of the ADS1298ECGFEPDK, and the other connects to the lead of an oscilloscope? I just want to make sure I have the right idea .


    Thanks,
    Noel Teku
  • 0 in reply to Noel Teku
    TI__Mastermind 38745 points
    Hey Noel,

    Checking the DRDY signal is as simple as clipping the reference connection of the scope probe to digital ground and touching the DRDY signal with the positive end of the probe. Then just look at the screen and see if there is a signal. If there is none, then its possible that you are not powered properly and more investigation needs to occur.

    Brian