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MD to PC with Sony

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I, like many people (so it seems), am a little upset with Sony's choice not to allow digital copies from MD to PC. I've hunted for software to do this, but have found nothing more than suggestions that I keep waiting and hoping.

My initial thought is to trap the signals sent to the MD to figure out how data is written, read, deleted; then write code to detect the MD and pull the files off.

Well, that sounds easy enough, I know. And I know there are a lot of people more talented at programming than I am that could do a better job. And I'm also fairly confident that if it were possible, somebody would have already done it.

So my question is this: What is it, technically speaking, that prohibits somebody from writing drivers that will allow digital copy from MD to PC via the USB cable?

Any details you guys/gals can throw at me would be appreciated.

--Ron

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I don't have a NetMD yet, but I am a professional programmer. So, from this point of view, I would say that it *might* be possible, but not necessarily. The problem is that the only stuff which is being sent from MD->PC is stuff like track information (titles, lengths etc). I would guess that the whole TOC is sent from MD->PC. In this case, it would be quite difficult to get the audio data as the computer doesn't request stuff, just the MD sends what it knows that OpenMG wants (which isn't what we want).

If we can tell it that the TOC is at a different spot on the disc, then there is hope. We would be able to tell it that the TOC is where audio data actually is, and it would just send it across. Once this happens, it is just a matter of interpretting the data. Unfortunately, I don't know that it is possible to request to the MD that it sends certain information - the MD might just send what it knows to be the TOC and that is all.

The next glimmer of hope lies in corrupting the TOC. There is a lot of stuff on a disc which is just addresses to other parts on the disc. If there is such stuff in the TOC then it might be possible to create a new TOC with false addresses which point to stuff which we want sent to the computer. The next hope is that the MD will actually send that stuff to the computer. If it doesn't then again, we are stuck.

An upload-proof MD would accept a command from the computer, which it would respond to by sending the area of the disc which is reserved for the TOC and nothing beyond that. It would also accept 2 more commands from the computer - one which writes to the TOC and one which writes to the audio area. In this case, note that uploading will always be from the TOC and nowhere else. If the TOC can be moved around the disc, then this method is flawed too (but I believe that the TOC is always in the same spot).

The other hope I have is that the TOC can change length. In which case, it might be possible to tell the MD that the TOC is so big that it fills the whole disk. When you ask the MD for the TOC, it would then send over the whole disc. Wooo smile.gif

My conclusion: It might be possible, but for Sony, it is possible for them to design a system where uploading is impossible. I'll definately look into it when I get a NetMD player, and I'm sure other people are trying. In anycase - help the cause - buy me a N10 smile.gif

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Thanks for the comments...I'm no professional programmer, though I've done my share of small stuff.

I was thinking more along the lines of recognizing the MD as a disk drive. My Sony digital camera is recognized as a removeable drive when I plug it in. So I was thinking maybe it would be possible to do the same for the MD, and be able to just pull the file off as if it were a file on a drive.

If that's possible, then would converting the audio format to mp3, CD Audio, etc., be an issue?

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sigh...

Speaking from the experience of hacking the MDH-10 (MD-Data drive) firmware, it's very unlikely that Sony left any avenues open in the released product. The TOC resides on a reserved set of sectors on the disc, so TOC sectors can never be confused with music (or data) sectors. (I already tried that, believe me.) Also, TOC, music, and data (if you care) sectors all have different block sizes. More specifically, while there are 2352 bytes per physical sector, there are header bytes, checksums, etc. that vary in length such that the data payload is different for each type of sector. A data sector only holds 2048 data bytes, the remainder is header and checksum. A music sector has 2332 music bytes, with only 20 header bytes. A TOC sector has something like 2306 data bytes. (Or is it 2308? I've forgotten, it's been a while...)

To address the specific point - on the MD-Data drives, there was a specific set of SCSI commands ReadUTOC and WriteUTOC for dealing with the MD TOC, separate from the regular SCSI Read/Write commands. And the regular Sony firmware explicitly prevented the SCSI Read/Write commands from accessing music or TOC sectors, they could only be used for data sectors. It doesn't seem that NetMD's protocol is at all related to SCSI or SBP2 (which would be the most logical first choice) but you never know...

(I believe) the only way in will be to dump the contents of the firmware, disassemble it, and then rewrite it. For the MDH-10 and MDM-111 drives, Sony at least included a rewrite facility in their firmware. You just needed to figure out the correct SCSI command sequence to write the new blocks. It helps to have the service manual for the devices, to give you a clue about what you're working with. For the MDM-111, since it was a desktop PC device, the work is a bit more straightforward since you can reprogram the firmware using a garden-variety EEPROM programmer. For the MDH-10 it's more pricy because it's a portable device and uses 3V parts.

I haven't seen a service manual for an MZ-N10 but I'd guess it may even be using 2.5V logic. I don't have an EEPROM programmer that supports these low voltage devices... The easiest route may be to obtain a NetMD home deck, like the 480, 780, or 980. Most likely they will still be using 5V logic devices.

It's highly likely that there is a USB command for rewriting the unit's firmware. They know that they never get it quite right on the first try, and there's always little bugs to fix. The MDH-10 went through some 21 firmware revisions. The MD-Discam was reflashable just by "booting" an appropriately encoded MD-View disc. I'd guess that every device they currently sell is shipped with rewritable firmware...

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