Suggestions for which chip

Designing hardware that uses VLSI Solution's devices as slave codecs such as an external MP3 decoder chip for a host microcontroller.
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DaveK
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Suggestions for which chip

Post by DaveK » Sun 2018-11-18 18:53

I've been asked to design a micro controlled WAV decoder/player. I'm at a loss as to which VS chip would be most suited for my project. The concept is as follows:

At power on: AVR processor 'reads' .WAV files from on board SD Ram (5 seperate files)
AVR processor loads the appropriate file onto SPI flash (one file per flash, 5 total SPI flash, 5 total VS processors)
AVR processor will instruct one or more of the 5 VS processors to play (once) the .WAV loaded into it's own SPI flash

The reason for 5 processors is that I'll be using an op-amp to sum all the output signals (acting as a mixer) so that the output of each of the 5 processors may be combined.

I'm having trouble deciding which VS chip is most appropriate for my project. I currently have a functional prototype using DF Player modules, but they are not appropriate for the final design.

Any thoughts would be immensely appreciated!

DaveK

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pasi
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Re: Suggestions for which chip

Post by pasi » Mon 2018-11-19 15:10

The ROM firmware of vs10xx chips receive the bitstream to decode through SDI.

You would need a custom boot code (loaded through SCI or from the SPI FLASH) for vs10xx to be able to play from SPI FLASH. Sharing access to the SPI FLASH also has a few challenges.

What would be the number of channels, bits per sample, and samplerate for the 5 streams? Would the AVR have fast enough SPI to read and transfer the required data to 5 separate vs10xx using one SPI and 5 chip select signals (and possibly other 5 chip select signals for their SCIs)?
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DaveK
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Re: Suggestions for which chip

Post by DaveK » Mon 2018-11-19 16:21

The transfer from the AVR will not happen in real time. At power on, the AVR will transfer one file to each SPI Flash memory, each SPI Flash will be tied then to an individual vs10xx. Once the files are transferred, the system will go into 'working' mode, and the AVR will only be used to trigger output on one or more of the vs10xx chips.

No need to be concerned therefore with sample rate, bps, etc., correct?

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pasi
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Re: Suggestions for which chip

Post by pasi » Tue 2018-11-27 14:38

DaveK wrote:
Mon 2018-11-19 16:21
No need to be concerned therefore with sample rate, bps, etc., correct?
Is there any latency requirement from power up to ready to play? The format and rate do affect that. And the size of the data per "module" would tell whether e.g. SPI RAM would be faster, better, and easier to use than SPI FLASH.

(I was also trying to figure out if there's an easier way to implement the system requirements than the multiple-player approach.)
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DaveK
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Re: Suggestions for which chip

Post by DaveK » Wed 2018-11-28 15:22

Latency would potentially be an issue - I could just as easily substitute SPI RAM for the Flash though.

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