PCM5121: No audio output when selecting the "Fixed process flow"

Hi Jeffres, 

Below are the our requirement for PCM5121, 

1) Need to apply the filters settings for Subwoofer and get audio out from DAC PCM5121. For this we have tried to apply the filters settings for the Default settings provided in the ROM. I have used "PCM5120 EVM with USB Audio input and analog Audio" and changed the filters coefficients and builded to the "PCM5121/22 EVM", through EVM we are able to see audio settings changes. But unfortunately not able to collect any source code in PPS and also not able to view the "Components interface overview" screen as its grayed out. 

To get the Source Code, I have used PPC 1.16 --> Through this i have used "PCM5142 EVM" part number option to connect to PCM5121/22 EVM. After successful connection I have used "Fixed Process Flow" through Programming miniDSP and then collects the Register dump and applied into our Linux driver. Kindly let us know is this correct approach.

But after applied settings, We are not getting any audio out through our system. 

As you suggested i have used the below write command into our system and this also not helped.

"i2cset -f 0 0x4D 0x02 0x10
i2cset -f 0 0x4D 0x2B 0x05
i2cset -f 0 0x4D 0x02 0x00"

Another way We have selected the option through amixer command but still no output.

2) The second requirements to get the Mono Out, We have used same approach loaded ROM settings but its not helpful to get MONO out, We are getting independent audio with respect to Left and Right Channel, its not mixed and provided single Mono Out.

Could you please help on the above requirements as we are get stuck into get the source code from PPS.

Hi,

Just to be clear, you are getting I2C commands through PPC and then putting them in PPS? Or are you scraping the I2C commands from PPS with PPC? In PPS, you can find all the registers changed for the miniDSP when you export the code. The register settings are in the exported code for the device. 

What have you tried to be able to get audio out? Have you had audio out before introducing Linux?

Best,
Mir

Dear Mir,

I did register dump from PPC1.16(PartNo: PCM5142) and tried to use the reg dump in linux driver code. But after writing those registers we are not getting the expected output with subwoofer changes. 

Have you had audio out before introducing Linux? --> In default driver setting also no output whenever we are selecting the "Fixed Process Flow".

Unfortunately we are not able to get the source code for "PCM5120 EVM with USB Audio input and analog Audio" through PPS.

Could you please guide is any specific version needed to get the source code for PCM5121 ROM based Process Flow. We are currently using the "Purepath Studio(Home Audio) MiniDSP 5.95" version.

Hi,

I was able to open this example process flow, I'm not sure yet how to export the registers needed. I have a coworker who can help, I'll follow up here tomorrow with what I learn. Thanks for your patience.

Best,
Mir

Is Any update on this?

Hi,

So sorry about the delay. I found in my computer's folders for PPS, "....\Documents\Texas Instruments Inc\PurePath Studio (Home Audio) MiniDSP 5.95\MyProcessFlows\Example Process Flows\ROM\PCM5120_USB_ROM" this is where the configuration files for this example process flow lies. You can see the default register writes for base_main_Rate44 and Rate48 in that folder.

Let me know if this helps, maybe we can try other methods if not. Have you been able to create your own process flow using PurePath Studio? I wonder if you can recreate the filter you need with your own block, not the ROM example. Then you should be fine to use the generated configuration files in your final application.

Best,
Mir

I have tried to recreate the own flow with the PPS but when we run these settings there is no audio output from PCM5121/22 EVM itself. As far i understand it PCM5121 DAC would supports only fixed process flow and not other flows. Could you please check this or could you please share latess PPS which supports to download the code.

I have read some other thread from TI shared the latest version  6.0 to the customer via email thread. Could you please check these as an high priority and help us to finish asap.

If we get latest PPS it will helpful for us to understand more on the "Dynamic Crossover Frequency" settings as well.

Regards,

Manimaran M.

Hi Manimaran,

I see your issue... I wonder if you can use the I2C Logging tool in PPS to get the I2C commands that are set when you click "Run" from the ROM command preset.

To enable logging, check this in Tools:

Then, the help file says that it will save the log file in your process flow folder, which is what I specified in my last post. 

Then, you can run these commands once the device is no longer active on PPS using PPC's "Direct I2C Access" page and see if this works to get audio working.

There are no newer releases of PPS since this is one of our older devices we don't have an official team supporting the software anymore. But I believe we will be able to get this to work with the software tools available. It seems like maybe your register dump from PPC didn't have the updated registers from what you ran in PPS, but if you do the I2C logging function in PPS, that will capture the changing registers that you will need to set.

Best,
Mir

Thanks Mir for the confirmation and I can able to see the changes through I2C Logging History.

We have one more requirement which is to apply the Dynamic cross over frequency to the DAC while its Running. For example we need to handle 40 Hz to 200 HZ crossover frequency. Is it any specific procedure to apply it, as it has lot of register changes happening for each frequency change how we can handle it. 

Hi Manimaran,

You can apply several types of filters with PPS, including parametric EQ, biquad filters, and FIR. You can make your own routing system with two filters, one for each part of the crossover, going to different outputs on the device. Here is a quick example of a signal flow I made with parametric EQ, you configure the filters by double clicking:

With this type of PPS workflow, you can export and build the code for this setup, which manifests as a set of I2C writes. You can then run these I2C writes whenever you want in your setup commands to integrate it into your project. Let me know if you need more help with this.

Best,
Mir