Lcd Backlight Brightness Hw Hack?


Epicenter

Very Active Member
Joined
Oct 9, 2005
Messages
2,068
Age
36
Location
USA
Website
www.epicgaming.us or http
It's imperitive a solution be found for this-- not just for visibility's sake and eyestrain (if it bothers you, it doesn't bother me) but that the LCD backlight uses enormous amounts of power, probably more than all the ICs in the system COMBINED! Trimming down its voltage will make a huge impact on battery life.

So it goes with most devices .. my laptop can be run at its default speed of 1.0 GHz or at 95-250 MHz, with or without its 802.11x radio on, but turning off the radio AND underclocking the hell out of the CPU makes barely a DENT in the kind of battery life gains I get from dropping to 60% backlight intensity.
 

Mudi

You're pushing your luck little man
Joined
Jan 25, 2006
Messages
815
Website
mudiweb.com
There's got to be a software method of toning the LCD down, can anyone find it in the firmware kernel sources maybe?
 

DaveC

Internal Development
Joined
Mar 4, 2004
Messages
9,208
Epicenter posted on Mar 18 2006 at 01:32 AM said:
It's imperitive a solution be found for this-- not just for visibility's sake and eyestrain (if it bothers you, it doesn't bother me) but that the LCD backlight uses enormous amounts of power, probably more than all the ICs in the system COMBINED! Trimming down its voltage will make a huge impact on battery life.

So it goes with most devices .. my laptop can be run at its default speed of 1.0 GHz or at 95-250 MHz, with or without its 802.11x radio on, but turning off the radio AND underclocking the hell out of the CPU makes barely a DENT in the kind of battery life gains I get from dropping to 60% backlight intensity.


Yes battery life is another plus for a backlight brightness control. Backlight brightness must have pretty much effect on that, so much so that the PSP won't even let you use the brightest setting unless connected to the mains.

So the advantages of this are better color saturation, better black level, better apparent contrast and improved battery life. I KNOW there is a software solution. I will wait awhile to see if some talented coder can suss it out. If not I will have to pull out my soldering iron and multitester and get hacking... I am hoping for the former 'cause I am a lazy bastard.
 
Last edited by a moderator:

jmetal88

Erm.... Woohoo!
Joined
Mar 31, 2004
Messages
1,838
Age
32
Location
Pittsburg, KS
Website
mikesweb.exofire.net
EvilDragon posted on Mar 17 2006 at 04:25 PM said:
A hardware fix might be hard. I can tell you which resistor it is - but if you change it, your screen will start flickering again.
The First Editions (the first ones) has a different resistor. Gamma and brightness was fine, but they began to flicker.

... and that flickering is starting to drive me CRAZY.

GP32z agreed to let me send it back, but I keep running out of extra money for shipping. :rolleyes:

EDIT: Yes, I've been told mine is too late a version for the flicker, but that doesn't change the fact that it's there.
 
Last edited by a moderator:

garteth

Member
Joined
Sep 22, 2005
Messages
207
Location
United Kingdom
Website
Visit site
I tried the 1.01 firmware on my 2nd edition gp2x and the screen was still bright, when I had a first edition it was much darker but I had a flickering problem. Very strange :blink:
 

EvilDragon

Administrator
Staff member
Joined
Mar 4, 2003
Messages
29,668
Age
43
Location
Ingolstadt
garteth posted on Mar 18 2006 at 05:32 PM said:
I tried the 1.01 firmware on my 2nd edition gp2x and the screen was still bright, when I had a first edition it was much darker but I had a flickering problem. Very strange :blink:

Errm, that's what I said above. Different resistor in the first First Edition units.
 
Last edited:
Top