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cmtk0101
20 Posts |
 Posted - 12 Apr 2003 : 13:19:47
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I have entered different values for the backlight Level, none of which work. I put zero for the BlightLevel4on and AF for the BlightLevel4off. I left the Timeout at 00 and also tried it at 3C. Regardless of what the Timeout is the Backlight is going blank, not dimming.
I checked the ADSMARTIO version in the debug and it looks fine. Here's the version:
SMARTIO Detected : PartType:0
x4434 Firmware:0x4017 Revision :L
UCB1200 Detected : ID = 0x1004
QUESTION: Am I leaving something out? Any suggestions why the backlight is not dimming?
Example:
[HKEY_CURRENT_USER\ControlPanel\Backlight]
"BatteryTimeout"=dword:3C ; 00=disabled; 3C=1 minute
"ACTimeout"=dword:3C ; 00=disabled; 258=10 minutes
[HKEY_LOCAL_MACHINE\Platform\Backlight]
"BLightLevel4on"=dword:0 ; operating backlight level (0-FF)
"BLightLevel4off"=dword:AF ; backlight level when "off" (0-FF)
Thank you in advance.
Jarret |
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akidder
1519 Posts |
Posted - 14 Apr 2003 : 08:42:05
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Hi Jarret. Try changing the values of BLightLevel4off. You'll have to experiment with different values to find the one that meets your application needs (eg. you might start by using a value of 20 or 30, which should dim the display enough for you to see that it's working). Setting the ACTimeout to, say, 10 seconds (0A), would shorten your test cycle.
You could also modify the backlight test in topic 451 to step slowly through the backlight levels to find one that met your needs. |
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cmtk0101
20 Posts |
Posted - 14 Apr 2003 : 09:25:10
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Drew,
I tried the dim level at 20 and now I see that it works. Thank you!
Jarret |
Edited by - cmtk0101 on 14 Apr 2003 22:45:28 |
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akidder
1519 Posts |
Posted - 18 Apr 2003 : 15:29:04
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Thanks for your note, Jarret. A couple other notes about automatic backlight dimming that may be helpful:- A value of FF switches the BacklightOn signal, turning off the backlight entirely. I.e. a value of FE is the dimmest value you can use.
- The amount of dimming depends on the revision of the GC Plus you are using.
Revision D and later of the GC Plus use a different BacklightPWM circuit, which generates 0 to 5V instead of 0 to 3.3V of previous revisions. This allows backlights like the LS520 to be dimmed completely.
I've updated the notes about backlight dimming in the GC Plus REG and HWT files, which you can download from topic 282. |
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