Trouble reformatting 80Gb 5.5G MacPod to FAT32 using mtools

[eeminy]

I've been having trouble reformatting my 80Gb 5.5G Mac iPod to FAT32 using mtools, and I'm hoping someone who's done this successfully can provide any hints as to where I'm going wrong. I unfortunately do not have adequate access to a Windows-capable machine, so easier paths are out.

I'm doing this from a G5 iMac iSight running OS 10.4, and mtools v3.9.11 (without the 20071226 patch, which gave me a compile error). I'm fairly comfortable with the command line and casual Unix commands, though not an expert. I'm including lots of details because I'm not sure which one might be relevant.

Briefly, I was able to write the 80Gb 5.5G partition table to my iPod, compile and install mtools-3.9.11 on my iMac, and get the mformat command to run, using the parameters in the instructions, without any error alerts. However,  as soon as the mformat finished, I went back to Disk Utility (where the iPod was still listed as being unmounted) and saw that the iPod's name had been replaced by "disk1s3" (its device number). It also refused to remount. I unplugged the USB cable and plugged it back in, at which point Disk Utility didn't see the iPod at all, and the device began cycling through partial boots every five seconds or so, getting to the non-backlit Apple logo before starting over. I was able to get into Disk mode and restore it to HFS+ using Mac iTunes Restore (which said the iPod was corrupted), so now I'm back where I started.

I think the problem may be related to the difficulty I had with the mformat parameters given in the instructions: mformat -t 2428 -h 255 -s 63 -S 2048 -M 2048 -F a:

Using these parameters as given gives the "argssize must be less than 6" error, whether you use -n or -s, the two alternatives suggested in the instructions. As described in this thread, in mtools v3.9.11 the -S option demands a "sizecode", call it n, where sector size=2^(n+7). Thus, for a sector size of 2048, the -S parameter should presumably be 4, and indeed, I was able to run the following mformat command without generating an error: mformat -t 2428 -h 255 -n 63 -S 4 -M 2048 -F a:

Does that look right? Any other ideas as to what might be going wrong? Also, what's the reason that Disk Utility can't be used to reformat the 80Gb MacPod (and, out of curiosity, does it affect the 60Gb Pod or is it an artefact of the 2048 sector size)? Does it just produce flaky results, or is there a firm reason it cannot ever work?

Many thanks for any suggestions or thoughts,
Emily

[Llorean]

If you just reformatted, when you unplugged and replugged your iPod you might've needed to force it into disk mode manually with the key combination. Otherwise it may have been continually trying, and failing, to load the original firmware causing problems and iTunes to think it's corrupted.

[eeminy]

Thanks for the response. That makes sense, and I'm embarrassed I didn't think of that. It did go into disk mode just fine with the two-button combo, and of course the Rockbox bootloader wasn't on there yet, so if it couldn't find the Apple firmware on its own, there wasn't much it could do but sit there and hyperventilate. I guess I expected that it would still be able to see the original firmware, and panicked when it started freaking out instead. I'll do it again tonight and see if I can install the bootloader in disk mode.

How do the partitions/formatting work on a MacPod, anyway, when the iPod can't be reformatted via Windows iTunes? I looked for a non-binary version of the partition table I'd loaded onto the iPod and couldn't find one on the site (though maybe I missed it). Is it keeping a small HFS+ partition with the Apple firmware, and reformatting the rest of the iPod as FAT32 for the Rockbox firmware and the file contents? If not, how does the Apple firmware get onto the new FAT32 area of the disk? Mac iTunes can't restore the Apple firmware onto a FAT32 iPod (and retain its FAT32-ness), can it?

[Chronon]

The (Apple) firmware is stored on a small "Blank" partition.  This is where Ipodpatcher also puts the Rockbox bootloader.  The HFS+ partition is your data partition and this is what must be changed to FAT32 in order for Rockbox to be installed.  The Apple firmware will read a FAT32 data partition just fine.

[eeminy]

I've edited my post from earlier this evening because I've figured out what was wrong and solved the problem.

Aha! The problem was that the Rockbox-provided partition table that I'd written to the iPod was not being recognized, so Disk Utility, iTunes, and the iPod itself were trying to parse the reformatted FAT32 partition as HFS+, with inevitably chaotic consequences.

The reason the partition table wasn't being recognized was that I wrote it to /dev/disk1s3, rather than the higher-level /dev/disk1, since /dev/disk1s3 was what both mount and the iPod's details screen in Disk Utility gave me as the disk device identity for the iPod.

It might be worth adding a line in the instructions to clarify this, by the way. I initially hesitated yesterday when I saw that the iPod was identified with "/dev/diskn₁sn₂" instead of just "/dev/diskn₁" like the example in the instructions, and I concluded, wrongly, that OS 10.4 must be using a slightly different naming system than whatever had been used as a model for the instructions, and I'd better use the whole name to be safe. A one-line caution in the instructions would steer users safely. The instructions should probably also be corrected to give the correct version of the mformat command (fixing the -S flag).

I don't know what the etiquette is for newbies with edit suggestions for the wiki -- I don't want to presume and rush in with edits, but I also don't want to seem to be fobbing off work for a volunteer project. I'm good either way. Anyway, thanks to you both for your helpful suggestions and information. I can't wait until my iPod finishes reloading all its contents and I can play with its new interface!

[Chronon]

It's a wiki, so jump right in if you have some improvements.   

There are registration instructions on the front page of the wiki.

[eeminy]

Yup, I saw them, but I know that some wikis do discourage edits from arrant newbies like myself. Thanks for the go-ahead.