[9front] aux/vga display mirroring

[9front] aux/vga display mirroring

[chris]

Good evening all,

I'm trying to setup a beamer (DH976) connected through vga with my
Thinkpad x200 for a presentation.

The beamer seems to show up. Although under vesa.

; @{rfork n; aux/realemu; aux/vga -t vesa -p}
vesa flag            Ulinear|Hlinear|Fsnarf
vesa sig            VESA 3.0
vesa oem            Intel(R)Cantiga Graphics Chipset Accelerated VGA BIOS 1.0
vesa vendor         Intel Corporation
vesa product        Intel(R)Cantiga Graphics Controller
vesa rev            Hardware Version 0.0
vesa cap             8-bit-dac
vesa mem            33488896
vesa dsp con        1 4 
vesa dsp act        
vesa mode           0x160 768x480x8 m8 packed
vesa mode           0x161 768x480x16 r5g6b5 direct
vesa mode           0x162 768x480x32 x8r8g8b8 direct
vesa mode           0x163 960x600x8 m8 packed
vesa mode           0x164 960x600x16 r5g6b5 direct
vesa mode           0x165 960x600x32 x8r8g8b8 direct
vesa mode           0x166 1280x800x8 m8 packed
vesa mode           0x167 1280x800x16 r5g6b5 direct
vesa mode           0x168 1280x800x32 x8r8g8b8 direct
vesa mode           0x105 1024x768x8 m8 packed
vesa mode           0x117 1024x768x16 r5g6b5 direct
vesa mode           0x118 1024x768x32 x8r8g8b8 direct
vesa mode           0x112 640x480x32 x8r8g8b8 direct
vesa mode           0x114 800x600x16 r5g6b5 direct
vesa mode           0x115 800x600x32 x8r8g8b8 direct
vesa mode           0x101 640x480x8 m8 packed
vesa mode           0x103 800x600x8 m8 packed
vesa mode           0x111 640x480x16 r5g6b5 direct
edid mfr            DPC
edid serialstr      
edid name           DH976
edid product        34409
edid serial         0
edid version        1.3
edid mfrdate        2015.1
edid size (cm)      0x0
edid gamma          2.20
edid vert (Hz)      48-120
edid horz (Hz)      31000-102000
edid pclkmax        170000000
edid flags          
edid 1920x1080@60Hz 
		clock=148.5
		shb=2008 ehb=2052 ht=2200
		vrs=1084 vre=1089 vt=1125
		hsync=+ vsync=+ 
edid 1920x1200@60Hz 
		clock=154
		shb=1968 ehb=2000 ht=2080
		vrs=1203 vre=1209 vt=1235
		hsync=+ vsync=- 
edid 640x480@60Hz   
		clock=25.175
		shb=656 ehb=752 ht=800
		vrs=490 vre=492 vt=525
		hsync=- vsync=- 
edid 640x480@73Hz   
		clock=31.5
		shb=664 ehb=704 ht=832
		vrs=489 vre=492 vt=520
		hsync=- vsync=- 
edid 640x480@75Hz   
		clock=31.5
		shb=656 ehb=720 ht=840
		vrs=481 vre=484 vt=500
		hsync=- vsync=- 
edid 800x600@60Hz   
		clock=40
		shb=840 ehb=968 ht=1056
		vrs=601 vre=605 vt=628
		hsync=+ vsync=+ 
edid 800x600@72Hz   
		clock=50
		shb=856 ehb=976 ht=1040
		vrs=637 vre=643 vt=666
		hsync=+ vsync=+ 
edid 800x600@75Hz   
		clock=49.5
		shb=816 ehb=896 ht=1056
		vrs=601 vre=604 vt=625
		hsync=+ vsync=+ 
edid 1024x768@60Hz  
		clock=65
		shb=1048 ehb=1184 ht=1344
		vrs=771 vre=777 vt=806
		hsync=- vsync=- 
edid 1024x768@70Hz  
		clock=75
		shb=1048 ehb=1184 ht=1328
		vrs=771 vre=777 vt=806
		hsync=- vsync=- 
edid 1024x768@75Hz  
		clock=78.75
		shb=1040 ehb=1136 ht=1312
		vrs=769 vre=772 vt=800
		hsync=+ vsync=+ 
edid 1280x1024@75Hz 
		clock=135
		shb=1296 ehb=1440 ht=1688
		vrs=1025 vre=1028 vt=1066
		hsync=+ vsync=+ 

I ended up switching from my laptop display to the beamer one like so:

@{rfork n; aux/realemu; aux/vga -m vesa -l '1280x800x32,#1'}

And back like so:

@{rfork n; aux/realemu; aux/vga -m vga -l '1280x800x32,#1'}

or: (there doesn't seem to be a difference between those in this case)

@{rfork n; aux/realemu; aux/vga -m igfx -l '1280x800x32,#1'}

 From my understanding, it should be the other way around.  Just a
understand problem on my side perhaps. Nothing that bothers me since
I know that it works at least.  Although an explanation could
be helpful.

There also seems to be some caching like logic to be involved. I have
to include the display number '#1' at least at the first call. Afterwards
it doesn't need to be included.

Anyways, I get to the switch leaving me with a blank screen.  Is there
a way to do a screen mirroring?  (Laptop screen synced with beamer
screen)

I imagine this to be not too trivial if even possible. But I was hoping
for someone who perhaps already tried.

Re: [9front] aux/vga display mirroring

[qwx]

>  From my understanding, it should be the other way around.  Just a
> understand problem on my side perhaps. Nothing that bothers me since
> I know that it works at least.  Although an explanation could
> be helpful.

So long as switching works and you get the right resolution, it
doesn't matter whether you use vesa or not.  The igfx driver really
only does mode setting.  There are some benefits, depending on your
machine though: you can adjust the brightness if you don't have
hardware buttons for it, you can have screen blanking that doesn't
deactivate the screen until you reboot, and you could use a hardware
cursor;  and of course use resolutions that you don't get with vesa.


> There also seems to be some caching like logic to be involved. I have
> to include the display number '#1' at least at the first call. Afterwards
> it doesn't need to be included.

If you mean that it's wrt.  the sequence of commands you show, igfx
doesn't recognize the ,#n syntax, it's for vesa only, so it will
either auto-detect the screen to use (as is the case here), or use a
vgadb entry that specifies which port (vga, displayport 1-5, etc.) to
use, vga by default.  Also, if you're not using -m vesa, you don't
need realemu(8).


> Anyways, I get to the switch leaving me with a blank screen.  Is there
> a way to do a screen mirroring?  (Laptop screen synced with beamer
> screen)

No, there's no support for using multiple screens in any way, unless
there's some trick specifically for mirroring that I'm not aware of.


Someone please correct me if I'm saying something stupid, it's been a
while since I messed with all this :)

Cheers,
qwx

Re: [9front] aux/vga display mirroring

[chris]

> So long as switching works and you get the right resolution, it
> doesn't matter whether you use vesa or not.

Indeed, I was just a bit confused. But it doesn't really matter.

> No, there's no support for using multiple screens in any way, unless
> there's some trick specifically for mirroring that I'm not aware of.

I was hoping for such a trick, but I didn't hold too many hopes.  I at
least wanted to ask before I settle with this setup.  It works well
enough like that.

Perhaps some wizard is going to add something to that thread in the
future.

Cheers