Audio player

I have a request for an audio player. The 12 audio files will be stored in a SD card (either mp3 or wav).

Each file will be 30 sec long and after user selection, it will be played in a loop.

All these are easy to implement with a DF Player and a PIC.

But we need the files to be locked so that cannot be copied from the SD card and played in another player from ours.

Any ideas welcome.

Ioannis

I don't think you can encrypt an SD card. A password filter may be all you need. The bigger you make it, the better. I know Microchip offers specialty security chips that could be added to your PIC project with random number generation and so forth. You may also simply increment all values by one, and on the read side, decrement all values by 1 so it comes out garbled without that translation.

Thank you Mike.

I know that Microchip has an encrypted, or so, unique serial number in some PICs but could not find that info in the parametric search. I can't recall how it is called.

Ioannis

esp8266 , audio in littlefs partition in flash would nail it, files can be modified with simple https browser i/f
on the devices own self generated access point

You mean ESP with in Arduino IDE, which needs good grasp of C, right?

I do not feel very confident on that IDE for a client project.
Thanks though,
Ioannis

Depending on the samples and quality, you may find that you need quite a bit of storage (SD card with SDIO interface). The power of the PIC to handle raw samples may be severely short to get a reasonable output. I suggest you look at the VS1003B MP3 chips that you can throw the samples at. This way, you do not need too much processing on the PIC.

another option you can evaluate is available on http://elm-chan.org/works/sd8p/report.html

Microchip Security Devices.

Jerson: Thanks for the info. The AT tiny is unbelievable!

Mike: thanks for the link.

Ioannis

We were doing this with an ISD5008. When that was discontinued we started moving into an ISD4003-08MPY. That was recently discontinued and are moving into an ISD17240. With a 4KHZ sampling frequency the 17240 will give you 8 minutes of record/playback.

Quote:

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You mean ESP with in Arduino IDE, which needs good grasp of C, right?

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i do , never tried it but it looks straight forward
https://github.com/earlephilhower/ESP8266Audio

cannot see how you can get in between df player and sd card to decrypt a file, you need to drive your own dac or pay for a proprietary
system that secures your audio data

I just remembered. There are these series of chips from Aplus that do exactly what you want. They are available in various capacities and can be segmented. So, you could record a few segments and then play them in any order you want perhaps even chain them together. This one I have used APR48000 in the past.

This thread might get you started http://www.picbasic.co.uk/forum/showthread.php?t=11369

These search links might expand your horizons even more
https://duckduckgo.com/?q=aplus+voic...nonical&ia=web

The APR and ISD chips are basically meant for human voice and not high fidelity. They're inteded for TAM (answering machines) use.

Hi Jerson.

Thanks for the info. The Aplus and especially the aPR33A3 might be exactly what I need.

Do they have distributer? Mouser or Arrow do not carry them.

Also the idea of ESP32 that Richard posted is a good alternative. Thanks for that too.

Ioannis

Hi Ioannis

Not sure how you can order Aplus where you are. Perhaps you may need to buy direct from the manufacturer in Taiwan. I used to source mine locally from a distributor in tiny quantities.

Best wishes