Rockbox Technical Forums

Support and General Use => Hardware => Topic started by: 1337 on January 11, 2019, 02:43:21 PM

Title: Clip+ error dc_writeback_callback
Post by: 1337 on January 11, 2019, 02:43:21 PM
Hi. Got a problem that appears periodically (like twice per week) on both stable 3.14 and latest builds.

something like:

*PANIC*
dc_writeback_callback ()
- Could not write sector
  xxxxx (error -3)  - always -3

Memory card - Transcend microSDHC UHS-I class 10 32gb - has no errors, was reformatted to fix this problem and not actively used (especially for writing  - music was rarely added and erased).
Title: Re: Clip+ error dc_writeback_callback
Post by: saratoga on January 11, 2019, 02:44:06 PM
Does it happen with 3.13? 
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on January 11, 2019, 02:45:37 PM
Yes.
Title: Re: Clip+ error dc_writeback_callback
Post by: saratoga on January 11, 2019, 03:57:15 PM
Than it isn't something we broke recently.  does it only happen with the SD card or does it happen on the internal storage too?
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on January 12, 2019, 06:26:55 AM
Do you mean ejecting memory card and testing by playing from internal memory? Not tried that, I can test. On latest daily firmware will do?
Also when I power on, and after menu is displayed, instantly pressing Home for resuming playback makes it stuck on "Loading" message without playing (and have to reboot, SD card reading indicator always on), to avoid this I wait for a sec or two.
Before 3.14 release often had a weird bug, while music plays, suddenly a very loud repeating noise (like TV white noise) appears instead of music (as far as I remember, sometimes it gave simultaneously dc_writeback_callback error, sometimes not - just usual playback screen). After 3.14 it appears very rarely, but still present.
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on January 30, 2019, 12:50:24 PM
Exact error message:

(https://i.ibb.co/kHLY9Nf/Clip-Error.jpg)
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on February 01, 2019, 01:38:46 PM
Exactly same error appeared again, both times when turning device off. Is it possible to determine if it's internal memory sector or sd card?
Title: Re: Clip+ error dc_writeback_callback
Post by: Bilgus on February 01, 2019, 11:24:05 PM
So did the error appear when the sdcard wasn't in the device?
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on February 03, 2019, 02:23:35 AM
It was inside.
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on February 03, 2019, 06:01:24 AM
Found software DiskExplorer for FAT disks, here are results of searching the error sector:

On internal memory:
(https://i.ibb.co/J7KFjmD/clip2.jpg)

On SD card:
(https://i.ibb.co/8rzRKtx/clip1.jpg)

Available views:
(https://i.ibb.co/wsRhGXx/clip3.jpg)
Title: Re: Clip+ error dc_writeback_callback
Post by: johnb on February 03, 2019, 07:24:08 AM
Hi 1337,

I had a similar message, when my internal flash was about to fail (I can't find the forum post right now).

I believe it paniced, when Rockbox tried to write
.playlist_control
in the .rockbox directory.

Be quick and try Bilgus bootloader that can boot from SD and won't touch the internal memory.
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on February 03, 2019, 11:41:30 AM
Hi,

Thanks, Bilgus bootloader works. I wonder if these disk writes eventually break SD card too.
Title: Re: Clip+ error dc_writeback_callback
Post by: Bilgus on February 03, 2019, 12:03:22 PM
Everything wears out eventually.
SD cards have a limited number of write cycles just like the flash in your player..
The upside being the SD card can be replaced once it wears out

Also a note for anyone else: While the boot loader works with any version of Rockbox, You have to use a special version of Rockbox *(for the time being) and have the file rockbox_main.<player> on the sd card to enable boot from the sd card

See: http://forums.rockbox.org/index.php/topic,51844.0.html
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on March 16, 2019, 11:28:07 AM
I was thinking, does clip+ have DRAM that can keep data while device itself is off by draining small amount of power?
Title: Re: Clip+ error dc_writeback_callback
Post by: 1337 on March 22, 2020, 01:08:00 PM
After trying latest stable firmware and boot from microSD, turns out the problem was in microSD 32gb card.
It was formatted to 16kb per sector, after formatting it to 32kb player starts without errors.