FS#11756 - Since using lamp plug-in the backlight and wheel light are incompatible

Attached to Project: Rockbox
Opened by Dave Cochrane (FLACtastic) - Saturday, 13 November 2010, 21:21 GMT
Task Type Bugs
Category Plugins
Status Unconfirmed
Assigned To No-one
Operating System Another
Severity Low
Priority Normal
Reported Version Daily build (which?)
Due in Version Undecided
Due Date Undecided
Percent Complete 0%
Votes 0
Private No


Sansa Fuze v2

I was using the lamp today but after a couple of minutes of use the LCD backlight went completely black until the wheel light turned off (then the backlight came back on). As soon as I moved the wheel, the wheel light came on and the backlight went off again (but the backlight then came back on again as soon as the wheel light went off again).

With much difficulty (due to the backlight going black for several seconds every time I turned the wheel) I managed to disable the wheel light permanently, and now the LCD light displays ok (although it is slightly dim - changing the brightness level makes no difference).

So the main bug is that I cannot have the wheel light AND the backlight on at the same time.

I have tried reverting back to an earlier build but the problem is still there (and I had to disable the wheel light once again to enable the backlight). The problem is also there if I use the Sansa OS (backlight only comes on when the wheel light is off). Very strange.

I don't know if anyone can give advice, but I would suggest not using the lamp plug-in due to the risk of this bug. Thanks for reading.
This task depends upon

Comment by foolsh (BenjaminBrown) - Saturday, 29 January 2011, 11:42 GMT
This sounds like it could be caused by two things.
1. A register bit is set incorrectly at boot time perhaps. Have you tried re flashing a boot loader?. If thats what it takes to install rockbox on this player, I haven't checked.
or I hate to say it.
2. Hardware failure. perhaps the lamp plug in should be disabled for now, from this target, until further investigation.
Comment by Boris Gjenero (dreamlayers) - Tuesday, 06 December 2011, 02:36 GMT
This seems to be the issue discussed in:,24964.45.html

I guess this is hardware damage which cannot be reversed. The maximum brightness was limited to 12 in r30227, and there shouldn't be any danger of this problem after that.