Originally Posted by Razor 116
@mdrejhon This program (http://www.entechtaiwan.com/lib/softmccs.shtm
) allows you to monitor the DDC/CI communication, unfortunately it only seems to monitor communication using DDC commands within the application. I tried it with the screenbright application to see if it would display the communication but it did not. It would seem that Linux would be the best shot at extracting the commands that the Nvidia drivers send to the monitor.
Yep, I did a little softMCCS research already at post 494 of HardForum thread
then read about the next 50 posts beyond. We used the VESA MCCS PDF v3
to figure out the DDC/CI commands. We found that the first byte 01 is a read command and 03 is a write command. The second byte is always the setting (e.g. 01 10 reads the current luminance value). We finally found that the FA command controls LightBoost OSD setting, but does not activate LightBoost alone.
There's a "Command Line" entry box in softmccs.exe that allows entering hex number (DDC/CI commands) to tell the monitor to change settings, etc.
Originally Posted by gzboli;1039571390
MCCS command 0xFA is controlling Lightboost brightness. Accepted values are 0 to 10. 0xFA lies in the "manufacturer-specific" area of the spec. Someone will have to test the BenQ to see if nVidia is requiring 0xFA on all monitors or if it is vendor specific.
No luck on finding the On/Off command yet. On the VG248QE, the OSD literally says "3D mode" when it is on, is this the same for the 27"?
EDIT: I should add that there are some command values that can be read which are not included in the capabilities string:
6C, 6E, 70 (Video Black Level, "persistent")
B0 (Save current settings or Restore Factory, "momentary")
FA (Lightboost brightness. Command type is returning as "momentary" but clearly this is a "persistent" command)
EDIT2: Hitting "Restore Defaults" on the "Setup stereoscopic 3D" page turns off Lightboost.
On both the BENQ and ASUS, the command 03 FA 00 01 through 03 FA 00 0A is changing LightBoost strobe lengths between 10% and 100% (1.4ms through 2.4ms) but only if LightBoost is already enabled.
We also found that a custom resolution Vertical Totals of 1147 or 1149 worked with LightBoost, but not 1143 (vertical sync pixels value too small), so the use of the resolution is also necessary. This can be done via nVidia Custom Resolution Utility, or via ToastyX's CRU.exe (Custom Resolution Utility).
So far, candidates for enabling LightBoost include (perhaps all the below):
- Specific timings (seems to help)
- Specific undocumented DDC commands (could be a factor too)
It appears the monitor is expecting more than one thing for LightBoost to be enabled...
Once we all discover what that is, then Radeon users can join the fun, and we'd have a system tray utility that can act upon a hotkey via a system wide keyboard hook driver (WH_KEYHOOK_LL). And LightBoost can then be re-enabled everytime a resolution changes (WM_DISPLAYCHANGED) -- good for stubborn games such as Battlefield 3. And no Control+T needed; and no stereoscopic mode problems or freezing. And it'd be easier to enable LightBoost (on one or more monitors) using just a simple system tray utility without installing any .reg or .inf files... User friendly button and hotkey access. I have the programming skillz, but I've not been able to crack the LightBoost protocol yet.
If you know Arduino construction (I have the skillz, but not the time this month, alas), there's a schematic diagram available in a document "Hacking Monitors Made Interesting
" for snooping the I2C serial line of your DVI/HDMI cable (DDC/CI). This could allow recording all the commands (without needing a Linux system), to figure out what the LightBoost protocol is.
It's definitely an initiating signal of sorts, rather than an ongoing synchronization signal, since LightBoost remains enabled when hotplugging from an nVidia computer to a Radeon computer (intentionally configured to the same custom signal timings).
If you are interested in doing further research (to make LightBoost easier) and find something new, let all of us know!
[/Lightboost-Hacking]Edited by mdrejhon - 3/6/13 at 6:46pm