Samsung YP-R0 rendered unusable?

[NathanV]

I installed rockbox (lightrom 4.6) successfully onto my YP-R0 but there was just one problem. When navigating to the microSD folder, it showed as completely empty. The microSD itself was fine and formatted correctly, as it worked on other rockboxed players.

I was trying out a few different things to attempt to get the files to show up on the YP-R0. I tried formatting the microSD card to other formats than FAT32, but by mistake I formatted the YP-R0's flash memory from FAT32 to NFTS. This seems to have been a death knell to the player. When turning on the player, it shows the Samsung logo for a few seconds, then the linux penguin for about 10 seconds, and then turns off. When turning on the player while it's connected to the computer's usb port, it does the same thing, except also automatically reboots and repeats ad infinitum. If I could somehow get the memory formatted as FAT32 I'm pretty sure the problem would go away, as it seems right now it can't boot from the NFTS formatted drive.

I've tried booting it in safe mode, but holding the back button after powering it on does nothing--it just goes to the penguin then turns off.
I've tried writing a FORMAT.MEDIA0, 1, and 2 file to the microSD and powering it on with it inside, but it does nothing.
I've tried placing the DRK files (Nand_killer, etc) on the microSD and powering it on with it inside, but it does nothing, and does not write the _done prefix indicating the file activated.

It seems like the only hope for rescuing the player would be some special file in the microSD card. Does anybody know of any further steps to take to try to salvage the player? I hope it can become more than just an expensive penguin viewer.

[saratoga]

I don't have that device so I can't specifically answer your questions, but there are instructions here for unbricking a device:

http://www.rockbox.org/wiki/SamsungYPR0

[lebellium]

We tried several things together yesterday.

Somehow the device can't enter the Safe Mode anymore (which is strange since the Safe Mode doesn't execute from the user memory media0 so I wouldn't expect formating it to NTFS being an issue for that)
Besides FORMAT.MEDIA0 on microSD card should link to the formatter.sh script embedded in firmware. Again I don't understand why it doesn't work. The system files are not in media0 so I think formating it to NTFS should not impact this.

Only the 2 Italian developers could confirm it for sure but they're kinda out of the YP-R0/Rockbox business.

As I told NathanV, only the leaked Recovery Tool could really help now. But it means building a special USB cable with a 300 Kohm resistor. Not everyone is able to do that...

[NathanV]

I've rescued the device!

I'm not sure exactly how it happened. Oddly, the cheap microsd to usb adapter I have been using had started to occasionally make my micro sd cards unreadable by my computer--the computer would show the card in the list of usable drives but could not access it. It occurred to me that somehow this might be causing the FORMAT.MEDIA0 file to not be read and thus nothing would happen. So I took one of the sd cards, cleaned and formatted it with chkdsk, and tried again. Also I wrote a .MEDIA1 and .MEDIA2 file just in case, which I'm sure I had done a bunch of other times in previous rescue attempts. I had no expectation that this would work or even the fact that the adapter was "messing with" my sd cards had anything to do with the FORMAT files failing to fix the yp-r0. I was just trying to consider anything and everything that would possibly make a difference.

So I put the card in the yp-r0 and turned it on. Samsung logo then Linux penguin, then it powered off. So I figured it did nothing like usual. I put the yp-r0 away and went back to my Fuze. I had just filled another sd card with some music and put the card in, but for some reason the Fuze wasn't reading the card, as I said, a problem that had happened before. I wanted to check if it was just the player or that card in specific so I took out the sd card and inserted the other sd card that I had just used to try to rescue the yp-r0 with the FORMAT files on them. It detected the sd card and I looked at the files and saw FORMAT.MEDIA0 and FORMAT.MEDIA1. And then I suddenly realized FORMAT.MEDIA2 wasn't there, and it struck me that that was probably what would happen if the file was read/"used". I ran to get my yp-r0 and turned it on and was amazed to see a screen from LightRom (was too excited to bother reading what it said). I immediately attached it to my computer and it went into safe mode as it was supposed to, and I was able to load rockbox and the rom back on. Device updated firmware and rockbox loaded. And happily this time there's no micro sd showing as blank issue, at least with this card.

lebellium, thanks a ton for answering all my questions on irc. I think that made me confident enough to keep trying the same fix even with no success.

edit: I notice I can see all my files in either /mnt/media0/<microSD1> and /mnt/mmc. What's the deal with that? Does the latter just point to the microSD as well?

[lebellium]

That's a great news 

However I don't really understand what happened with the FORMAT.MEDIA files. As far as I know media2 doesn't exist so I don't know what FORMAT.MEDIA2 really does. Maybe it formats both media0 and media1. Strange that the developer didn't tell me though
From what I recall and can find in my R0 documentation, the FORMAT.MEDIA0 file would disappear once executed and you would get a MEDIA0.FORMATTED.log file instead.

Well, it doesn't really matter, at least it worked!

edit: I notice I can see all my files in either /mnt/media0/<microSD1> and /mnt/mmc. What's the deal with that? Does the latter just point to the microSD as well?

They both point to the same microSD card. The thing is that usually on the other Rocbox targets you only have Files\<microSD1> visible but on the R0 you see everything due to the RaaA (Rockbox as an Application) port based on a Linux kernel.

Note that you can start browsing from where you want (for example mnt/media0/Music). Just select the directory, long press and select "Start File Browser Here"