• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 46 subscribers
  • Views 452 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.

ADS1013: Issues with i2c access

Bruce Thompson3
Prodigy 40 points
Part Number: ADS1013

Hi,

I am using the ads1013 and I am having trouble accessing the device through i2c.  It almost appears that I have a non working part but wanted to make sure I have everything connected correctly and I am writing to the correct address.  The result is when I try to write to slave address 48 with data 01(trying to access the config register) I never get an ack on the first write of address 48 so data 01 never gets sent.  I have observed this on the scope.

This is how the chip is wired.

  • +1
    TI__Mastermind 31655 points

    Hi Bruce,

    Your connections do seem fine to me. The address 48h is correct when the ADDR pin is grounded. To see if something may be wrong with the part, you can also try to send the general call address and look for a response.

    The ADS101x responds to the I2C general call address (0000000) if the eighth bit is 0. The devices acknowledge the general call address and respond to commands in the second byte. If the second byte is 00000110 (06h), the ADS101x reset the internal registers and enter a power-down state.

    One thing to note is that high speed mode (clk above 400khz) must be activated first. To activate high-speed mode, send a special address byte of 00001xxx following the START condition, where xxx are bits unique to the Hs-capable master. This byte is called the Hs master code, and is different from normal address bytes; the eighth bit does not indicate read/write status. The ADS101x do not acknowledge this byte; the I 2C specification prohibits acknowledgment of the Hs master code. Upon receiving a master code, the ADS101x switch on Hs mode filters, and communicate at up to 3.4 MHz. The ADS101x switch out of Hs mode with the next STOP condition

    Regards,

  • 0 in reply to Scott Cummins
    Prodigy 40 points

    Hi Scott,

    Thanks for the reply.  After looking at this again the problem was a bad part as I suspected.  I replaced it and everything worked as expected.  You may close this ticket.

    Thanks for the help,

    Bruce