PCM1865EVM: configuration

Hi Malay,

The PCM1865EVM allows you to stream audio directly over USB with the I2X board. I'm not sure what exactly you are looking for, but the default state of the EVM should do what you require. I would recommend you look through the PCM1865EVM user's guide and let me know if you have any questions about the configuration or run into any issues.

Best,

Zak

hi Zak, 

Thank you for your quick response. 

I have gone through the EVM user guide. But i am not understanding how i can collect that digital audio data to PC through PurePath Console.

I have given analog input to PCM1865EVM from FM tuner Lout and Rout output. 

But at console interface i am not able to understand how to get that digital audio data. 

Can you help me with some example/reference for the single stereo channel interface configuration with PCM1865.

And also is it possible to get the digital I2S audio data to PC through the USB-I2X interface. If yes than how to get that data. As in PurePath console i am not able to find how to get that digital audio data.  

Hey Malay,

Do you only require a single stereo input? If that is the case then you may prefer to use the PCM1863 instead of the PCM1865, which has the same functionality but has 2 channels compare to 4.

At least for the initial bring up and testing you should not need to program the EVM at all. By default the device will operate with a 48kHz sample rate using clocks supplied from the PCM9211 (this is mode 0 in the user's guide.) VINL1 is initially set up for a single-ended input and routed to ADCL1 and VINR1 is also set up for single-ended input and routed to VINR1. The IC will also default to 24-bit I2S output. If these are not the settings you want, then let me know what you would like to adjust and I can share a script.

The purepath console GUI is only used to configure the IC using I2C commands, it does not interact with the USB audio. If you want to record, you will need to use an audio software such as Audacity. Our device should enumerate as Line (TI USB Audio UAC2.0) and you will select that as the capture source. There are other software options you could use too, but I am most familiar with Audacity if you run into issues setting this up and need some assistance!

Best,

Zak  

Hi Zak,

Thank you very much for all these clarification. This really helps in further development.

So I am going to interface 2 stereo input channel (4 ADCs) with PCM1865evk and for configuration and audio data communication i am going to iMX8M Mini dev board which has I2C ( for configuration ) and I2S (for digital audio data capture) ports. For this i won't require that USB-I2X board right.

I may need more clarification for

1. I am not able to find I2S pin headers (BCK, LRCK, DOUT) on PCM1865evk board, How can i connect that board to iMX8M kit to get digital audio data through I2S interface. 

2. I am directly connecting Lout1, Rout1, Lout2 and Rout2 from FM tuner to jumper (Lout1, Rout1) J3 and (Lout2, Rout2) J2 of PCM1865evk through connectors. I want to make sure these connections are correct. And the Multiplexed two channel output i will get from DOUT pin (orange test point is given ).

3. Also can you provide some reference script for such 4 channel ADC interface with 48KHz sampling rate and 24 bit word data format. I have gone through the datasheet for the same. But if i can get some reference that will be helpful. 

Hey Malay,

I have responded to the I2S connections in your other thread here: https://e2e.ti.com/support/audio/f/6/t/924283

Regarding the input connections you will want to check the the ADCX1_INPUT_SEL_X registers. By default both left channel ADCs will be muxed to VINL1 and both right channel ADCs will be muxed to VINR1. You will want to change the connection of the second left ADC most likely to VINL2 and similarly for the other right channel ADC. You can of course use other pins if you would prefer to.

As I mentioned for the mode you are looking for there is no need for a script since this is the default configuration of the device. However, if you would like to see what the register writes would be, you can use the "Direct I2C Read/Write" tab of the GUI to dump the registers in CFG format to the output window. 

Best,

Zak