<![CDATA[ChipMusic.org - SOLVED: GBA volt pot not changing backlight contrast]]> https://chipmusic.org/forums/topic/18844/solved-gba-volt-pot-not-changing-backlight-contrast/ Sun, 31 Jul 2016 16:31:51 +0000 PunBB <![CDATA[Re: SOLVED: GBA volt pot not changing backlight contrast]]> https://chipmusic.org/forums/post/246663/#p246663 nanode says:

FIXED!

I had to solder a wire from GND 32 to 103 on the back of the board and the picture is 100% perfect.

]]> Sun, 31 Jul 2016 16:31:51 +0000 https://chipmusic.org/forums/post/246663/#p246663 <![CDATA[Re: SOLVED: GBA volt pot not changing backlight contrast]]> https://chipmusic.org/forums/post/246661/#p246661 2xAA says:
katsumbhong wrote:

Did you test the pins of the pot to make sure your wired it to the correct pins? Did you wire the negative or the positive to the pot?

The trimmer (pot) is on the GBA's main board, hopefully nanode didn't solder anything to it - you don't need to for this mod.
The trimmer is just used to control the signal level to the LCD screen I believe.

]]> Sun, 31 Jul 2016 11:37:25 +0000 https://chipmusic.org/forums/post/246661/#p246661 <![CDATA[Re: SOLVED: GBA volt pot not changing backlight contrast]]> https://chipmusic.org/forums/post/246660/#p246660 katsumbhong says:

Did you test the pins of the pot to make sure your wired it to the correct pins? Did you wire the negative or the positive to the pot?

]]> Sun, 31 Jul 2016 10:32:20 +0000 https://chipmusic.org/forums/post/246660/#p246660 <![CDATA[Re: SOLVED: GBA volt pot not changing backlight contrast]]> https://chipmusic.org/forums/post/246659/#p246659 2xAA says:

Does the trimmer (pot) stop turning at some point or does it turn forever?
If it turns forever it's probably broken from excessive force.

The pic you posted up looks like it does only just need some adjustment with that trimmer for sure. It's the same dim colours I got when I installed my AGS-101 screen.

With the 40-pin adapter cable you should solder a wire from one of the pads on the adapter cable to a point on the GBA's main board.

Grab the instructions PDF from this Gist and double check.
The Gist says you may need to solder a cable to ground to avoid washed out colours.

Good luck!

]]> Sun, 31 Jul 2016 09:15:24 +0000 https://chipmusic.org/forums/post/246659/#p246659 <![CDATA[SOLVED: GBA volt pot not changing backlight contrast]]> https://chipmusic.org/forums/post/246658/#p246658 nanode says:

Hey all!

So I'm trying to transplant a working mainboard into a case with an AGS 101 backlight. It's 40 pin and the new board that I have IS compatible and is just a newer/cleaner version of the previous.

I'm at the point where I have to test the voltage and brightness of the backlight and I'm running into some trouble. No matter how far or what direction I turn the potentiometer, the backlight stays at the same setting of "way too bright to see anything."

Ref:

Is there a known fix? If it helps; I don't have a soldered ground connection from the ribbon cable, but I don't think 40 pin cables need one if my knowledge serves me right.

Any help would be greatly appreciated!
-Sam

]]> Sun, 31 Jul 2016 04:13:05 +0000 https://chipmusic.org/forums/post/246658/#p246658