Rockbox Technical Forums

Third Party => Repairing and Upgrading Rockbox Capable Players => Topic started by: RockBoxNewB on April 11, 2017, 02:55:23 AM

Title: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: RockBoxNewB on April 11, 2017, 02:55:23 AM
Hi all,

Some of you might already be familiar with my "experimentation" on iPod Classics from some of my other threads - starting out by replacing the original Apple stock firmware with Rockbox, then slipping into hardware modding by replacing weak batteries and finally ending up taking the entire device apart. My drive for experimentation never really stopped, since the thirst for better firmware, longer battery life and bigger storage got a firm hold on me and never let me go.
Let me be honest with ya: I am neither particularly skilled on the software nor on the hardware side - so what I did was pretty much trial-and-error-based and led to the destruction (in whole or in part) of 2 iPods.
While nagging both Tarkan Akdam and the Rockbox team for information on compatibility or troubleshooting, I noticed that you'll find cross-references between both "camps" - but not one cumulative resource you can address. Tarkan will explain how to use his adapters with Rockbox, but in case iFlash and Rockbox don't work properly together, he's going to say "I'm not part of the Rockbox team so I don't officially support it or guarantee anything". Some RBers have also worked with iFlash, but information is rather scarce and very disseminated overall. That's the intention behind this thread... my hope is that those who have also experimented like me, might post their ideas and solutions here, just to bring together some experiences that might help us jump to conclusions.

Let me start with the modified devices I've got in front of me right now, maybe someone has chosen a similar way:

- iPod Classic 6G ("thick" - originally 160GB)
   Rockbox (daily build as provided on 19 March 2017)
   iFlash DUAL (1 SD card - 256GB)
   1900mAh extended battery

- iPod Classic 7G ("thin" - originally 160GB)
  Rockbox (custom build provided courtesy of [Saint])
  iFlash QUAD (3 micro SDs of 128GB, total 384 GB)
  2000mAh extended battery

This should suffice for now, if anyone is interested, I can post the experiences I made in detail, but I'll leave that out for now so this post does not end up too long.

If you tried some of this yourself or if you consider it, please join me and let me know what you think!

Best,
RBNB
Title: Re: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: Frankenpod on April 13, 2017, 03:49:37 AM
Not sure what you are asking, but I'm curious as to how well your 6g works.

  I thought the 6g can't handle more than 128gb (with a non CE drive) in OF mode?  So to use 256gb you'd have to sync using rockbox mode (either by using emcore or dual-boot while not using OF), and (I get that some people deny this, but I think its the case) in both my experience and many other people's RB's USB handler doesn't work terribly well for syncing, at least with flash mods (might be OK with original HDs).  I find you tend to get file copying errors, sometimes subtle (playback glitches) occasionally very obvious (directory corruption).
Title: Re: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: RockBoxNewB on April 16, 2017, 08:04:41 AM
Hi Frankenpod,

I'm asking for exactly that: the things you came to know about mods like this, and your ideas around possible problems :-)
Because what you describe is exactly what I struggled with, too. I always used syncing while in Rockbox mode since either the Apple OF was not possible because of the 128GB limit or it just was quite a hassle to use. The result: Barely any copying procedure worked like a charm, sometimes it took me months to notice that hundreds of files went "missing" because there was some corruption. Now that you mention it, I finally know that this was not a mistake on my side at some stage of the installation process, but obviously a rather frequent issue.
I tried everything, from different builds to different bootloaders (EMcore vs. the praised "new bootloader"), different adapters (Dual SD vs. quad micro SD) etc. My Dual SD-modded iPod seems to be free from directory corruption (only one of the 2 slots used, though). My 7G had 4 micro SDs inserted in the first place. As an experiment, I removed one of them, restored it and used EMcore instead of the new bootloader (I know, I know, it is not recommended to use it). For some reason, the corruption *seems* to have gone away on that device, too. I was wondering if the removed card or the new BL made the difference. I haven't been testing it for long enough to be sure, though.
I was hoping to get some more insights on those problems from other people's feedback!

Best,
RBNB
Title: Re: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: Frankenpod on April 16, 2017, 11:33:31 AM
Just as an aside I think the new bootloader deserves its praise - for 7th gens at least its a massive step-forward, precisely because it solves that syncing issue, and I'm grateful to the RB dev who has continued to work on it (I get the impression there aren't many active devs these days).

Apart from that, it's a pity the rockbox sync is problematic, because it reduces the usability of 6th gen ipods, which are cheaper than the 7th gens.

The other problem I've found is that RB+classic+sd combo is extremely sensitive to the brand+capacity of sd card used.  Some brands don't seem to work with rockbox+classic.  Change the sd card type, use ipod video instead or use OF and the problem goes away.  It's especially annoying as it means my slim case+larger battery+quad adaptor 800gb combo will only work on a 5th gen, not a classic, and I prefer the final-gen classic (I have a couple of 768gb dual-adaptor classics but those have to be thick cases to fit larger batteries).
Title: Re: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: saratoga on April 16, 2017, 01:04:54 PM
The other problem I've found is that RB+classic+sd combo is extremely sensitive to the brand+capacity of sd card used.  Some brands don't seem to work with rockbox+classic.  Change the sd card type, use ipod video instead or use OF and the problem goes away.  It's especially annoying as it means my slim case+larger battery+quad adaptor 800gb combo will only work on a 5th gen, not a classic, and I prefer the final-gen classic (I have a couple of 768gb dual-adaptor classics but those have to be thick cases to fit larger batteries).

I doubt that the problem is the SD card itself.  Probably there are various timing issues in the driver when using those adapters, and differences in SD card performance hide or expose them, making data corruption more or less likely. 
Title: Re: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: Frankenpod on April 17, 2017, 07:22:27 AM
The other problem I've found is that RB+classic+sd combo is extremely sensitive to the brand+capacity of sd card used.  Some brands don't seem to work with rockbox+classic.  Change the sd card type, use ipod video instead or use OF and the problem goes away.  It's especially annoying as it means my slim case+larger battery+quad adaptor 800gb combo will only work on a 5th gen, not a classic, and I prefer the final-gen classic (I have a couple of 768gb dual-adaptor classics but those have to be thick cases to fit larger batteries).

I doubt that the problem is the SD card itself.  Probably there are various timing issues in the driver when using those adapters, and differences in SD card performance hide or expose them, making data corruption more or less likely.

I have no knowledge on which to base an opinion, so can only assume it's likely you are right.  I have wondered whether it's to do with the peculiar media formatting the ipod uses, as that's an obvious difference between 5th gens and later models.  I've found the problem always manifests itself when building the database, presumably because that's the point where RB itself writes to the card.
At least the "7th" gens with the "right" type of cards seem to work reliably enough, for whatever reason.
Title: Re: iPod Classic + iFlash adapter + Rockbox - a summary
Post by: RockBoxNewB on April 24, 2017, 02:48:22 PM
Hi all,

thanks for your valuable insights on this. Personally, I didn't realize that there was such a difference between 5G, 6G and 7G iPods. I tried a 5G iPod Video once. The database is a crucial feature to me, and (at least at that point) I couldn't find any build with the LOAD TO RAM feature. This made using the DB extremely tedious since it took minutes to build the lists, so I decided I need to pick a more modern iPod with a better processor. I cannot say if there were no syncing issues back then, though...
It also seems I need to correct my statement about my iPod with the iFlash Quad adaptor... today, one song was shown as "lost" again (both from file view and from database). Strangely, after I had turned off the device for a couple of minutes, the song was suddenly found again... what the hell? Is the concept susceptible to heat after all (although Tarkan claims otherwise), maybe worsened by the fact that I use one of the extended batteries?
Hm, now I'm completely sure which bootloader to use. I was convinced that the new bootloader was extremely vulnerable to file system corruption issues...but I actually lost track with the different versions offered (V8, V8 designware, "V1.0"). Anyone have any recommendation?

Best,
RBNB