• State
  • Locked Locked
  • Replies 6 replies
  • Subscribers 30 subscribers
  • Views 714 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.

CC85XXDK-HEADSET Development Kit

Ignacio Linares
Expert 1655 points


I have a PurePath Wireless Headset Development Kit (CC85XX-DK-HEADSET).  It works great out of the box with a audio provided from my PC via Line Out to the Line In of the CC85xx master board transmitting to the CC85xx slave board which has headphones connected to it.  I would like to know how to set it up so that I can plug in a microphone to the Master board Line In and hear the audio on the Slave board on the headphones.  I plugged a microphone in, but didn't hear anything.  I suspect there is a setting or configuration that needs to be changed to amplify the microphone inputs (??). 

Is there a specific type microphone that works best?  Does it have to be an active microphone?

  • 0
    TI__Expert 7160 points

    Hi Ignacio,

    You have to enable mic bias. Do the following:

    • Go to the Master's Audio Interface panel. Select Enable in the Custom setup field. Then a new panel shows up in the project tree called Audio Device Customization. Click it.
    • Click the Set all sequences to default button and a bunch of i2c transactions will show up.
    • Select the INACTIVE to LOW-POWER sequence and paste in the lines:

    w 30 00 01 # Select register page 1

    w 30 33 44 # Enable MICBIAS connected to AVDD

    • Select the LOW-POWER to INACTIVE sequence and paste in the line:

    w 30 33 30    # Disable MICBIAS connected to AVDD

    Best regards

    Kristoffer

  • 0 in reply to Kristoffer S
    Expert 1655 points

    I am stuck at the moment.  Neither board works.  I suspect I have it programmed incorrectly.  I would like to get back to the original demo load on the master and slave board.  However, I have tried using the configurator to do this but I haven't successfully restored it back.  Obviously, I am doing something wrong, but not sure what.  What is the correct configurator option for the default demo load?  I wish this had been included in the help files on the configurator - maybe a suggestion for improvement on the documentation.

    Also, on the configurator which way is upstream and downstream relative to the master and slave boards?

  • 0 in reply to Ignacio Linares
    TI__Expert 7160 points

    Hi Ignacio,

    Go to the start page in the PPW Configurator and double-click the example project: CC85XXDK-HEADSET_Preloaded Demo (see picture below). Then go to the Flash Programming panel and flash one board with the master image and one board with the slave image. You should now have out-of-the-box firmware. 

    Down means from master to slave. Up is from slave to master.

    Best regards

    Kristoffer

  • 0 in reply to Ignacio Linares
    Expert 1655 points

    OK - I am back.  After you showed me in the picture where to go, I realized I was loading the 85XX-DK preloaded demo and not the 85XX-Headset preloaded demo.  So, now I am back to the original working out of box demo.

  • 0 in reply to Ignacio Linares
    Expert 1655 points

    I now have the microphone working after implementing the I2C sequences you recommended.  I don't really hear much latency, but before I demo this to a customer, I want to be sure it is set to the absolute minimum.  What do you recommend I set the latency parameters to in order to make it the minimum possible?  Currently, the sample rate is 44100, audio latency samples (default) to 1984 samples (44.989 ms).  I see other settings, but I am not sure what the trade-offs implications are of going to a lower sample rates which seems to give better latency.  Recommendations?

  • 0 in reply to Ignacio Linares
    TI__Expert 7160 points

    Hi Ignacio,

    It's difficult to hear latencies this low: the latency in the PPW protocol is adjustable between 10.6ms up to 42.6 ms (for 48kHz sample rate). Latency has to be chosen with care since there is a trade off between link robustness and latency. The longer latency the more robust audio streaming (less probability for muting events) and vise versa.

    Applications were low latency is key is for example live music (microphones, wireless guitar amp etc) since the musicians are able to feel the latency. Applications were low latency is less important is for example cable replacement (streaming music to wireless speakers). If you choose maximum latency in this application you will only experience a 42 ms delay from pressing "Play" to when the audio is heard in the speakers. 

    You should always choose as long latency as possible to get the most robust link.

    -Kristoffer