LDSP - audio optimised i.MX 8M Plus QuadLite

So what are your plans with this board, if I may ask?
End goal is a set of boards to drop into my busted Meridian 568.2 with room correction, hdmi & atmos outputs. It's been with me for 20 years so time for a refit!

I'll be making a new rear panel etc.

Second board will be used in a 562 enclosure - that will have a load of I/O over or multichan spdif or something. I was looking for firewire controllers and how to interface with the 8m plus... :)

Pics from meridian-audio.info

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562v2 rear

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That's the long term goal anyway. Still thinking...
 
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CamillaDSP or filters in Pipewire

The 8M Plus ASRC is available as an asla plugin - but limited functionality to what the ASRC unit is capable of.
I believe it can also perform many taps per channel too!
https://github.com/nxp-imx/imx-alsa-plugins
Google - NXP EB808 - for comprehensive performance report
"Vybrid ASRC Performance Audio Analyzer Measurements"
Better than 120dB THD, 144dB SNR.

NXP Linux Yocto Project BSP for Desktop PoC (Proof of Concept)
https://github.com/nxp-imx/meta-nxp-desktop/tree/lf-5.15.71-2.2.0-kirkstone
 
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The 8M Plus ASRC is available as an asla plugin - but limited functionality to what the ASRC unit is capable of.
The plugin supports up to three streams with a total of ten channels, just like the spec sheets say, or am I missing something?
I believe it can also perform many taps per channel too!
https://github.com/nxp-imx/imx-alsa-plugins
My filters are quite long at 65536 taps per channel. Earlier in the thread you mentioned 128 taps per channel, that would not work. I don't think the CPU would have a problem with a few of those extra long filters, though. A CPU based approach would have the advantage of being generic enough that there is no hard dependency on one specific type of SoC.

For my endeavours I always try to avoid non-standard solutions because I don't have much leisure time to invest. I prefer getting something going with off the shelf solutions that waste a few CPU cycles to not getting anything working at all.
 
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The plugin supports up to three streams with a total of ten channels, just like the spec sheets say, or am I missing something?
The hardware IP is a different beast in the 8M Plus series. Max floating point performance is about 800*10^6. Powerful, but defintely not enough for 65k taps for many channels.

You have 5V only at the connectors. How do you want to generate the opamp supplies?
Off board. This is a tiny SBC and not really an all in one + supplies. For a small DC to opamp supply i've had good results with the R1283K001C into a Cmultiplier. Something like.
https://www.nisshinbo-microdevices.co.jp/en/pdf/datasheet/r1283-ea.pdf

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Prototype board I made a while ago....

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DDR4 routed! Working on I/O again now.

I had to reduce the i2s by a channel pair I was not able to source eth ICs so had to go with higher pin count eth = less one less set of i2s pads.

SAI1 - rx pins 6 & 7 had to be moved to support ETH ports.

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Updating the models and silks. Had to change a few BoM items to parts available to me.

@ariendj - assuming the sample boards work out I can send you one for testing. It might be early July.

I hope to be in a position to order the first boards next week.

I've left enough room near the USB-C power in port to implement a filter arrangement like

https://www.we-online.com/components/media/o150133v410 ANP007d EN.pdf


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Finally pressed the button and ordered 2 boards with the MIMX8ML8.
That's the variant with GPU+NPU as it turned out to be cheaper now they're in mass production!
Working on the Linux kernel dts tree in preparation so I'll make a git repo for those changes too.

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