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Mod an MP3-CD player to accept HDD

Hey,

Been looking to make a portable MP3 player. So started looking at SBCs and stuff. Figured out that its difficult to beat the commercial HDD-MP3 players (US$200 for Neuros 20GB MP3 player!!) on price/size bcoz a SBC is a general purpose computer whereas a commercial HDD-MP3 player is just that - an MP3 decoder.

So I figured what if the CD on a regular CD-MP3 player can be replaced with a HDD?? Should it be perfectly possible. The Mp3 CD is the ISO

9660 that we burn on our PCs. So the CD-MP3 player must recognise that. So emulate the HDD to look like a ISO 9660 CD and we should be done (there are minor details like power supply, ofcourse ;) )

And thats the question. How does one emulate ISO 9660 on a HDD. Or can the CD-MP3 player read FAT32? I found some guy selling an emulator but its too expensive (~US$250).

My guess is that they should read FAT32. Why? Look at the cheap MP3-Flash players with detachable pen drives. The pen drive is formatted to be FAT16/32. One idea was to plug an external HDD via USB to the MP3-Flash player after detaching the Pen drive. However, such combos have lots of controls on the pen drive and the cheap ones don't have a LCD display good enough to wade thru GBs of MP3s.

Hints/Suggestions/Pointers? The goal is the cheapest portable Mp3 player per GB!! :)

The working solution will be documented and posted for everyone to see. (Trust me ;) )

TIA,

Siddhartha

Reply to
Siddhartha Jain
Loading thread data ...

Have a look here:

formatting link

HTH,

Vadim

Reply to
Vadim Borshchev

Thanks Vadim. But I am more interested in modding a MP3-CD player to accept HDD. Why?? A MP3-CD player costs ~US$25. In this amount, you get a MP3 decoder, DAC, LCD Display, IDE/ATAPI controller(?). So if I could add a ~US$50 2.5 inch HDD to it then this would be the cheapest HDD-MP3 player by far!!

I opened up my older Audio CD player (Sony) and found a legacy 14-pin cd drive controller. Need to procure a MP3-CD player and open that up. Assuming that a MP3-CD player has a IDE/ATAPI controller, any clue what would it take to emulate ATAPI (by a ATA disk)? I see two problems:

  1. ATA to ATAPI bridging or ATAPI emulation in hardware.
  2. The controller on the MP3 CD player might be hard-coded to read addresses covering only 650MB (CD size)?

Any help?

TIA,

Siddhartha

Reply to
Siddhartha Jain

That seems highly unlikely, especially for $25.

For your other question, "mkisofs" in every Linux distribution can make iso9660 images in any size.

Reply to
Clifford Heath

In article , Siddhartha Jain writes

Standalone MP3 CD players do not get involved in IDE or ATAPI. They handle the raw data from the disc pickup directly. It is not possible to do what you are suggesting.

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Tim Mitchell
Reply to
Tim Mitchell

The Fujitel MP3/VCD/ACD player retails for Rs.1250 (Approx US$25) in India.

The Mp3 CDs are burned in the ISO9660 format. If a CD-Mp3 player does not have a IDE/ATAPI controller, how else would it read the CD? And all the open Mp3-CD player designs I came across on the net include a IDE/ATAPI controller.

formatting link
and
formatting link

Btw, I opened an older (4 year) Sony ACD player and found that it has a Sony CXA2542AQ controller chip for the cd-drive with a 14-pin connector. Now the 14-pin is the legacy cd connector. Another old panasonic VCD/ACD player had a 16-pin connector. Looks proprietary. Looking for a Mp3-cd player to dissect :)

Cheers,

Siddhartha

Reply to
Siddhartha Jain

Then why do Stand-alone MP3-CD player projects like the ones I mentioned below use a IDE controller (Intel 8255A)? And if no controller is involved except for motor control then why do manufacturers require that you burn the Mp3 CD in ISO9660 format?

Just curious.

Reply to
Siddhartha Jain

In article , Siddhartha Jain writes

Because the stand alone player projects do use an IDE/ATAPI drive, as that's the only economical way of buying a CD drive.

And the CD player is designed to read the ISO9660 format because that is the standard format that is used by everyone's CD burners.

--
Tim Mitchell
Reply to
Tim Mitchell

IIRC an 8255 is a fairly simple parallel port adapter.

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Reply to
CBFalconer

CBFalconer wrote in news: snipped-for-privacy@yahoo.com:

I was thinking the same thing. I never thought of the venerable 8255 I/O expander as an IDE controller. I mean try an command the 8255 to READ DMA and see what it does. :-)

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- Mark ->
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Reply to
Mark A. Odell

So you are saying that if I used the ACD player drive then I don't need the ATAPI controller? How do I read filenames for display then?

Yep, I know but the point was that if you used any other format other than ISO9660, most MP3-CD players won't read it. Now that would not be the case if the Mp3-CD players just took the raw stream from the lens and fed it to the MP3 decoder. Right?

I looked at the specs of a MP3 decoder chip. It said that the chip can take a raw stream and ignore the garbage. So what you say must be right but then the same question. How do they read filenames and browse folders?

Other than MP3-CD players, look at the USB Flash MP3 players. Now these players (~US$50) can read FAT32 filesystem on the flash drive. So they must have an intelligent controller that does more than just pump raw streams to the MP3 decoder.

Ofcourse, the best thing to do would be to open up a Mp3-CD or Flash-Mp3 player and look at the insides. If anyone already has, could you please share a few pics and specs? Or else, I will buy one of these and do that (Ehh, US$25 is not that small a amount here :) )

Thanks for your patience Tim!

Cheers,

Siddhartha

Reply to
Siddhartha Jain

ATAPI has nothing whatever to do with the *structure* of the data, it's an electrical interface (and protocol) to read the raw data. It only exists to funnel a SCSI-like command set over IDE hardware. Neither is useful to a stand-alone player.

Wrong. They take parts of the raw disk stream from here and there, and interpret the results as an ISO9660 filesystem which tells them where to find files etc. Then they "open" those files by reading the mp3 tag from the end, which gives them track/artist/album/etc to display. When you select "play", they read the section of the disk's raw data which corresponds to the audio content for the selected file, and feed it to the decoder. None of this needs IDE/ATAPI, just the ability to seek and read raw data.

Yes. But that doesn't require ATAPI either, of course.

You'll find a custom controller chip which probably contains all the iso9660 stuff lumped in with the drive controller and possibly even the display driver.

Reply to
Clifford Heath

Well, someone seems to have done it. Check this:

formatting link

:)

Siddhartha

Reply to
Siddhartha Jain

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