• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 97 subscribers
  • Views 282 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.

DM644x I2C is sending out I2C ACK even when no devices are present on the bus?

pathfinder
Genius 12790 points

DM6443 I2C is sending an ACK to fixed address of device that doesn't exist.  Even w/ all 'good' devices removed from the bus, it still sends out the ACK?  Can anyone think of why this would happen?  Is it a rogue I2C driver initiating the ACK incorrectly due to some other event?

DM6443 w/ LSP 2.x, custom board, had issues w/ I2C.  Removed all devices from the bus to investigate issue deeper.  SDA/SCK have external pullups just like the DM6446 EVM.

Thanks.

  • 0
    TI__Genius 12790 points

    To clear this up and put more clarity into the original question.

    Customer found that when no external devices were on the I2C bus and he tried to read/write from address 0x0A - they would get an ACK.  Turns out that the I2C block inside the silicon uses this address for itself, hence the ACK that didn't make sense.  I did not find any specifics about this in the data sheet or I2C Peripheral UG.  So just FYI if anyone sees this.

    Regards,

    Marc