iPod video - Disk mode fails, sector size problem. PLEASE help!

[eltonart]

Hi. I'm building a iPod 5.5 with 80Gb drive for rockbox. I installed a new logic board and new 80Gb slim hard drive and then succesfully restored the ipod in itunes. I then installed rockbox but after reboot I recieve error message "*PANIC* Unsupported physical sector size: 4096".

I know how to fix the error using a custom complile of rockbox (I've done this before successfully).

The problem is that now I can't get the ipod back into "disk mode" in order to fix it. I can reboot the iPod OK but when I hold play and middle button I still get the error message.

Thanks in advance for your help! Elton.

[Chronon]

If you are seeing that message when doing the button combination then you are doing it too late.  Try holding it as soon as the screen blanks from holding Menu+Select.

[eltonart]

I'm doing it immediately after the screen goes dark for the restart. I used to do it on my old Ipod and it worked every time. Thanks but I dont think that's the problem.

[saratoga]

AFAIK the disk mode will always work unless you've physically broken the player.

[eltonart]

Thats what I thought too, but now I'm not so sure. Its only a theory but I wonder if the drive tries to start with the incorrect sector size that the head somehow gets out of allignment. If the Ipod is unable to start in disk mode then I wonder if it will try and start in normal mode???

Diagnostic mode doesnt work either. What worries me is that the Ipod was working after I used Itunes to restore it before I installed the bootloader and Rockbox. The logic board and hard drive are brand new!

Anyone able to confirm how the boot-mode and diagnostic mode works in more detail and what happens if anything is wrong? I assmue it uses the built-in firmware to load and should bypass the bootloader???

[saratoga]

The bootloader USB mode is on a ROM chip on the logic board.  I don't see how doing anything to the hard disk short of smashing it could impact the ROM.

[Arj]

I thought the standard build supported 60/80GB drives?  Do different 80GB drives have different physical sector sizes?

[torne]

The standard build supports the drives Apple shipped in the 5.5G iPod Video which have 1024 byte sectors. Other drives obtained from alternative sources may have any sector size.

However, most or all drives other than the one that came with the 5.5G 80GB iPod should work fine *without* the workaround to handle the larger sector size (in fact they should work *better*). That specific drive does not follow the ATA spec correctly. We just don't currently have a better way of handling this case. I am planning on taking a look at it when I have time.

[TexasRockbox]

What is the manufacturer and model of the slim 80GB drive?  Is it listed on this page: http://www.rockbox.org/wiki/HardDriveReplacement  ?

[Arj]

Is there an easy way to determine what drive you have in an iPod w/o having to open up the case?  I ask because I have a 120GB Video I bought off eBay and had the same issue as the OP with the 4096 sector size.  So I installed the unsupported build that had the changes needed and it is working fine.  The one thing I am not sure about is if the LBA needed to be set to 48 (if I recall correctly) or not and maybe the drive info would help me determine that.

[torne]

Lba48 is needed if your drive is over 128GiB (137GB), but enabling it when it's not needed is fine. Most drives other than the original disk in the 80gb 5.5g work fine if you just *remove* the max sector size definition and will work faster that way.

[Arj]

torne, thanks for your replies.  They have been very helpful.  Your last comment prompted one more question:  you put remove in quotes, so that suggests you don't really mean to remove the definition.  Maybe you just were implying that we can comment out that definition?  I'm just surprised by this suggestion and am willing to try it, but want to be sure I understand it.  I think you are saying we could use the standard build and just comment out the size definition and it should be good for most drives (80 - 128GB).  Correct?

@eltonart:  did you ever get back into disk mode?  If not, did you try leaving the hold switch on and plugging it into a USB port?

[Llorean]

Those are not quotes. They're asterisks, which are often used to denote emphasis in text-based communication when options such as "bold" aren't available (and a habit some people get used to, so that they do it even places like these where bold is available).

[torne]

Yeah, sorry, I was on my phone and I couldn't be bothered to find the square brackets to type the bbcode for bold. You can either comment it out, or change it to just #undef instead of #define (with no value). With no value specified it basically disables the workaround to specially handle different sector sizes, and assumes the hard drive will take care of it, which almost all hard drives *do*, and they do it more efficiently than our code does.

[Arj]

  Ugh, need to get my eyes checked!  Sorry about that, they are indeed asterisks and, yeah, I would have seen that was for emphasis.  Again, I appreciate the helpful responses folks.  Very much appreciated!