CM6631 usb audio interface .... any good?

Hi, could some one please help me to solve my issue.
I have CM6631A device. I tried to update firmware using Firmware tool: first of all I erased firmware and then unlugged and plugged in the device. But now windows cant't recognize it and I cant install any driver. VID and PID seemd like also changed and now VID=0D8C and PID=5200. Google shows it's now C-Media USB 2.0 Mass Storage Controller and I can't see the device in Firmware tool.
How can I flash new firmware?
 
Hello,

I'm looking for a chip who can accept spdif, USB and I2S as input and output audio stream on other I2s to feed a dac. A kind of digital multiplexer. An MCU control the chip to choose the input (i2s, usb or spdif) with digital bus (i2c ou spi or more simple GPIO).
I need spdif to bring coax/toslink input, USB and I2s input for bluetooth audio module.
CM6631A seems to be a good solution, but do you think it's possible to do that with a custom firmware for CM6631A ?

Thanks for help! It's for the design of an audio amp.
 
Pm39LV512 is no more available in digikey or mouser. It is EOL . What could be possible replacement?

I didn't already use CM6631 but I read somewhere on this thread that a bigger flash // can fit. Just take care about page size, eventually timing and off course pinout if you want replace a dead flash.

For example a microchip SST39VF010 sould be OK, but wait for a more experienced guy than me who already use CM6631 with other flash than the one of ref design.
 
Hi,
I've recently started a new design using the CM6631A. The Flash in the reference design is old and the datasheet och the CM6631A does not include timing requirements for the flash memory.

Are there any answers/information on the question if the SST39VF010 works as a replacement to the SST39LF010? I'm thinking of 70ns vs 45ns read access time.
 
Hi,
I have a question regarding configuration of the CM6631A using the configuration tool.

Terminal type selection "Speaker" seems according to documentation to select XMDAC as output for I2S stream from USB (interface 1 according to firmware spec).

But what recording interface is selected? I would really like to use the S/PDIF input interface (inteface 6 according to firmware spec) but the configuration tool does not support selection of input interfaces. Any suggestions or ideas?
 
Me too!
But it seems that the people here ignores inputs. :ashamed:
I see no reason to design the pcb and not leave the inputs available, SPDIF or even I²S.

I agree, it seems very rare to discuss inputs using CM6631A.

My amplifier design uses an optical S/PDIF as its primary input. I would really like to use the CM6631A S/PDIF input to forward digital audio to the USB interface. A USB-connected external NUC/Laptop/DSP receives digital audio that is processed (Digital Room Correction) and returned via USB to the CM6631A. Received audio is then forwarded to a SRC to provide the DAC with a fixed sample rate and low jitter audio stream and so forth...
 
Last edited:
But where is it possible to find this firmware?

Somewhere back in this thread someone posted a link to where the CM6631 development kit could be downloaded. Don't know which post it was in, but possibly before the post I linked to. IIRC, it does not include the C51 compiler which is needed too. Up to you to find that, but if you look around enough maybe possible.

Maybe try reading here: https://www.diyaudio.com/forums/dig...m6631-usb-audio-interface-65.html#post5369052
 
Last edited:
Oh... are the audio stream interfaces of the CM6631A (like MIC In, Line In and SPDIF In) selected by the Windows mixer setting? I thought this was controlled via firmware, but I might got it all wrong :)
With the help of the firmware you can choose the availability of i/o's (playback and records), using the mixer you can choose which of the available i/o's are active at the given moment.