Using a custom EDID with arcade monitors

[cools]

As a note, not sure if any one realized about this. I'll write a little how-to when I have some time. It allows creating a custom EDID through Switchres. This adds the required custom modeline into a custom EDID which is loaded by the kernel on boot, making the kernel patches redundant. It's limited to one modeline by now, which it's plenty enough for most purposes. The good thing is that this modeline is made based on the same crt_range settings used by GroovyMAME, so you can make the both match in geometry, something that was not possible before. Besides the custom EDID should mask the physical one in the monitor, if any, preventing its factory modes from getting in the middle.

Success.

Code: [Select]

$ switchres64 640 480 60 --monitor arcade_15 --edid
$ mv edid.bin edid-15khz.bin
$ switchres64 512 384 60 --monitor arcade_25 --edid
$ mv edid.bin edid-25khz.bin
$ switchres64 640 480 60 --monitor arcade_31 --edid
$ mv edid.bin edid-31khz.bin
# mkdir /usr/lib/firmware/edid
# cp edid*.bin /usr/lib/firmware/edid
# sed -i 's/BINARIES=""/BINARIES="\/usr\/lib\/firmware\/edid\/edid-15khz.bin \/usr\/lib\/firmware\/edid\/edid-25khz.bin \/usr\/lib\/firmware\/edid\/edid-31khz.bin"/g' /etc/mkinitcpio.conf
# nano -w /boot/syslinux/syslinux.cfg 
  Add to APPEND for 15khz: drm_kms_helper.edid_firmware=VGA-1:edid/edid-15khz.bin fbcon=rotate:0
  Add to APPEND for 25khz: drm_kms_helper.edid_firmware=VGA-1:edid/edid-25khz.bin fbcon=rotate:0
  Add to APPEND for 31khz: drm_kms_helper.edid_firmware=VGA-1:edid/edid-31khz.bin fbcon=rotate:0
  For vertical monitors change rotate to 1 or 3
Xorg happily switched into the 640x480 31KHz modeline in the config whatever I booted up with. Apparently it's possible to use the EDID binary with certain Xorg drivers directly... So I'll try that soon as well.

[cools]

 

Xorg uses the EDID data it finds from KMS automatically! I can boot up with no Xorg configuration files and everything works.

Groovy/Xorg isn't restoring the previous mode on exit however. Hmm. Doesn't matter if I specify a different modeline from the EDID (which works).

The thing that's astonishing me is how fast it is within the same range - 15khz modeswitching occurs so quickly there's barely any interruption on screen. Windows was never like that.

[Calamity]

Awesome job Cools, you've been faster than I

Xorg uses the EDID data it finds from KMS automatically! I can boot up with no Xorg configuration files and everything works.

Yeah, I remind when testing this you didn't need to add a modeline to Xorg, it just took the default one from the EDID, which is great.

Groovy/Xorg isn't restoring the previous mode on exit however. Hmm. Doesn't matter if I specify a different modeline from the EDID (which works).

You mean after exiting GroovyUME? Please check the log, especially the exit sequence when the modes are deleted and the desktop mode is restored, just in case there's something odd.

[cools]

Yeah, when exiting GroovyUME back to the frontend. I'm done for today but will check when I get a chance on the weekend.

Using a custom EDID is wonderfully elegant.

[cools]

Yeah, I remind when testing this you didn't need to add a modeline to Xorg, it just took the default one from the EDID, which is great.

And with the nouveau and i915 drivers? The latter would be incredibly cool.

[Calamity]

And with the nouveau and i915 drivers? The latter would be incredibly cool.

I haven't tried anything outside of ATI cards yet with this EDID thing. I'm a bit worried about how the interlaced modes will behave because the EDID specification is a but fuzzy regarding those. It required some trial & error to get them working and I'm not sure if it will be valid for non-ATI cards. But definitely will be worth testing.

[cools]

The i915/xf86-video-intel drivers are behaving strangely. KMS is enabled and I can feed them the 25khz EDID file, but Xorg fires up in 720x400 no matter what I do to try and set a different modeline. The Xorg log shows that it's reading the EDID from the kernel (SWR manufacturer, 512x384 available but without a refresh rate, which is strange), but it won't list any of the custom modes I put in xorg.conf. The log also gives this line "[KMS] drm modesetting not supported". xrandr lists no modes available.

I'm set up now so I can play about some more later but if I had to guess what was going on at the moment the EDID isn't quite right (as proposed) but because it exists the intel driver won't let you work around it. Assumption though.

[Calamity]

The i915/xf86-video-intel drivers are behaving strangely. KMS is enabled and I can feed them the 25khz EDID file, but Xorg fires up in 720x400 no matter what I do to try and set a different modeline. The Xorg log shows that it's reading the EDID from the kernel (SWR manufacturer, 512x384 available but without a refresh rate, which is strange), but it won't list any of the custom modes I put in xorg.conf. The log also gives this line "[KMS] drm modesetting not supported". xrandr lists no modes available.

I'm set up now so I can play about some more later but if I had to guess what was going on at the moment the EDID isn't quite right (as proposed) but because it exists the intel driver won't let you work around it. Assumption though.

It would be good to know if without the EDID .bin the drm modesetting is supported at all. It may just mean the Intel drivers support for KMS is poor still, are they don't like this custom EDID for some reason. I admit I'd been surprised if it had worked.

[cools]

Yeah, that's next on my things to try. I don't know if the monitor supports EDID or if the I/o will block it, or off using a blank bin file will help. Everything I can find seems to imply that the Intel drivers only allow KMS if they have an EDID present, and disabling attempts to enable KMS is a normal workaround for weird hardware.

[cools]

Embarrassingly I was putting the modelines into the wrong monitor (the Radeon is still plugged into the PC and Xorg detects it, but disables it) 

Not having much luck with anything custom, but I've got it displaying 640x480 which is progress.

[cools]

Looking like low res patches to the kernel module are required. Patching the Xorg driver in the same way as the radeon/NVidia (there's an identical line for resolution) hasn't helped, and if I'm reading the kernel source and existing patches correctly the i915 dotclock min is 20000-25000 depending on the chip used.

The EDID is read fine from an arcade_31 preset with 640x480@60 in it. 640x400@60 also works. So I think your EDID code is fine, it's just the driver rejecting it. The Xorg driver is okay handling the lower modelines and tries to switch to them but the display just vanishes.

I've overwritten what look like all the dotclock minimums with 4000 and am compiling a fresh kernel to try.

[Doozer]

Hi Calamity,

I have spotted an issue with the EDID code. Manufacture year is calculated from 1990. here is the fix. Nice addon.

Do you know if it is possible to fake the EDID at boot using an eeprom? I am planning to try 15hHz EDID dot clocks with BIOS. If anyone has some experiences, fell free to answer.


edid.c change

--- ../groovyarcade.switchres/SwitchResLinux-1.52/edid.c        2014-06-30 08:38:19.400136667 +0200
+++ edid.c      2014-06-30 09:30:38.842251248 +0200
@@ -48,7 +48,7 @@
        edid[16] = 5;
 
        // Year of manufacture
-       edid[17] = 2014 - 1999;
+       edid[17] = 2014 - 1990;
 
        // EDID version and revision
        edid[18] = 1;

[cools]

So far nearly everything is working beautifully in Manjaro Linux (a fork of Arch) from the live distro.  I've noticed a small issue on some games (primarily vertical/TATE mode ones), in that it remains at the game's resolution instead of switching back to the previous one (which I think cools might've reported as well).  In fact, it's virtually the same for any game that goes below a horizontal resolution of 320 seems to do so (meaning that the patched X.Org drivers are in fact required to switch back properly).  Not so much a bug, but something for users to keep in mind.

I was using the patched drivers, but a stock kernel. Didn't have motivation to test more, drive swapped back to my Windows install just to play some games

Do you know if it is possible to fake the EDID at boot using an eeprom? I am planning to try 15hHz EDID dot clocks with BIOS. If anyone has some experiences, fell free to answer.

Lots of searches suggest you'll be wasting your time. http://forum.arcadecontrols.com/index.php/topic,119387.msg1265058.html#msg1265058

I'm fairly certain that BIOS just looks at EDID (monitor) and available VESA (VGA BIOS) resolutions and matches them up, so you'd need to reprogram the VGA BIOS (like the ArcadeVGA) even if you could fake the EDID (the Soft15khz dongle does it, but doesn't provide 15khz BIOS).

I've never found concrete information on doing this - in fact Andy Warne at Ultimarc has described how much of a pain the AVGA was to develop, requiring support from ATI under an NDA.

It's something I'd consider buying an Arcade VGA for as it turns out. My newest motherboard has a UEFI bios that runs in 1024x768, which is unusable on any of my cabinets. The older stuff that has 640x480 is tolerable with a split display - not nice to look at but at least visible and possible to navigate, but the newer one requires me to drag out an external monitor if I ever need to get into the BIOS. If/when the SDL lag is sorted and I can use Linux for GroovyMAME rather than Windows (the AVGA limitations in Windows compared to CRT_Emudriver are not attractive), I'll probably pick up a card.

[Calamity]

I have spotted an issue with the EDID code. Manufacture year is calculated from 1990. here is the fix. Nice addon.

Thanks! I'll fix it as soon as possible.

Do you know if it is possible to fake the EDID at boot using an eeprom? I am planning to try 15hHz EDID dot clocks with BIOS. If anyone has some experiences, fell free to answer.

It looks like it's totally up to the gpu manufacturers to decide how to handle the EDID information. I read that the Soft-15khz dongle works with Nvidias enabling 15 kHz out of the box under Windows (I never tested this). But my ATI cards just ignore the dongle.

[Doozer]

@Calamity, @Cools

Thanks for the head-up. I have developed a piece of hardware able to disable the video signals when hsync is out of the 15kHz range or convert a 31kHz signal to 15kHz at the price of a duplicated picture (like jammaSD). I am now investigating the EDID side and have tested on my workbench EDID injection which was intended to allow boot in a vesa safe 31kHz/60Hz mode. Let's seen how far I can tweak the EDID.

[Calamity]

Thanks for the head-up. I have developed a piece of hardware able to disable the video signals when hsync is out of the 15kHz range or convert a 31kHz signal to 15kHz at the price of a duplicated picture (like jammaSD). I am now investigating the EDID side and have tested on my workbench EDID injection which was intended to allow boot in a vesa safe 31kHz/60Hz mode. Let's seen how far I can tweak the EDID.

Hi Doozer, that sounds very interesting. If I may suggest an addition, it would be great if that thing could actually force the arcade monitors to be detected by applying the expected load, this is problem #1 with modern video cards: http://forum.arcadecontrols.com/index.php/topic,138903.msg1445694.html#msg1445694

[cools]

If you need any testing done I'd be happy to mess around in future.

I'd love to see a dongle with some dips/jumpers on it that specified what syncs the monitor was capable of (15/25/31/38) and provided valid EDID specs for whatever was selected / divided the signal as appropriate.

It's really irritating me that the motherboard I've bought forces 1024x768 for BIOS access... In touch with support now to see if they can help.

[Calamity]

It's really irritating me that the motherboard I've bought forces 1024x768 for BIOS access... In touch with support now to see if they can help.

Get used to this Same for W7 boot menu. Good news if you have a 15/25/31 capable monitor are 1024x768 could be easily halved to 25 kHz in the same way that 31 kHz is converted to 15 kHz.

[cools]

(Hence the request for a split mode dongle )

It'll be interesting to see what happens by faking the EDID. Or even trying an AVGA with this motherboard, but I'm not spending £75 on a test - I do enough pointless spends as it is.

[Doozer]

Hi Doozer, that sounds very interesting. If I may suggest an addition, it would be great if that thing could actually force the arcade monitors to be detected by applying the expected load, this is problem #1 with modern video cards: http://forum.arcadecontrols.com/index.php/topic,138903.msg1445694.html#msg1445694

Do you have a card model in mind? My latest ATI is HD5450 and works well.

By the way, have the grounding of DDC ID pins been tested to force monitor detection? Because putting a 1Kohm/75ohm load with a wrong chassis can permanently damage it. Keeping in mind that the following trick disable EDID usage (same pins)

Code: [Select]

VGA ID pins set-up

4    11   12
ID2  ID0  ID1

n/c  n/c  n/c   no monitor
n/c  n/c  GND   Mono monitor which does not support 1024x768
n/c  GND  n/c   Color monitor which does not support 1024x768   <-- could be suitable
GND  GND  n/c   Color monitor which supports 1024x768

GND means connected to ground
n/c means that the pin is not connected anywhere


[Doozer]

If you need any testing done I'd be happy to mess around in future.

I'd love to see a dongle with some dips/jumpers on it that specified what syncs the monitor was capable of (15/25/31/38) and provided valid EDID specs for whatever was selected / divided the signal as appropriate.

I have plenty of flash and saving 4 EDID is not an issue. Selection with dip switches could also be supported (Currently I have only 1 switch for 15/31 KHz selection).

I am curious, why 38KHz ?

[elvis]

I've never found concrete information on doing this - in fact Andy Warne at Ultimarc has described how much of a pain the AVGA was to develop, requiring support from ATI under an NDA.

Andy's goal was slightly different though - many modelines configured in the card's BIOS (and being forced to deal with a limit on how many modelines he could support).

I'm sure it's not a trivial matter, but hacking just the default/bootup mode would be a lot less work by comparison.

What would be really nice would be a hardware device that could just block signals greater than a particular sync rate.   Lots of clever folks around these days making things like SLGs and the like.  I wonder if any of them could be convinced to have a crack at something like this?

[edit] Of course, there's the J-Pac which will line-halve.  But it's a touch overkill if you don't need the JAMMA connectivity.  All the same, I love my J-Pac in my JAMMA cabinet.

[cools]

I am curious, why 38KHz ?

For those few arcade monitors that will do SVGA. Cover all bases.

I'm sure it's not a trivial matter, but hacking just the default/bootup mode would be a lot less work by comparison.

You'd think so, however in many years I've not seen anything about it.

What would be really nice would be a hardware device that could just block signals greater than a particular sync rate.   Lots of clever folks around these days making things like SLGs and the like.  I wonder if any of them could be convinced to have a crack at something like this?

[edit] Of course, there's the J-Pac which will line-halve.  But it's a touch overkill if you don't need the JAMMA connectivity.  All the same, I love my J-Pac in my JAMMA cabinet.

True. Such a device has been suggested numerous times but no-one's ever bothered - presumably the market is too small to bother with.

[Doozer]

To my understanding the biggest issue is not the SLG itself, but rather the signal clocking and its upscaling to native resolution. Therefore you need to have a multi-sync LCD with vertical ranges compatible with old CRT refresh (or multiple of it) and a proper scaler to achieve identical visual output. Not talking about inherent latency introduced with such a system.

[cools]

What happens if you force windows to see a generic monitor driver for SVGA or similar?

[Calamity]

What happens if you force windows to see a generic monitor driver for SVGA or similar?

I don't think you can even do that in W7.

[cools]

What happens if you force windows to see a generic monitor driver for SVGA or similar?

I don't think you can even do that in W7.

You can, I just tried. However: it still reads the EDID data from the monitor and allows all the modes available to be used.

Using the EDID override code works, however you need to supply enough blocks to cover everything that the monitor itself supplies:
http://msdn.microsoft.com/en-us/library/windows/hardware/jj133967(v=vs.85).aspx

[cools]

Yup, I was just able to tell Windows to set my laptop resolution to 1600x1200 by using that sample file. Works fine.

Now to try with SwitchRes.

[cools]

Using SwitchResLinux to generate an EDID.BIN, then converting that into the required registry settings as per the Microsoft article gets me this showing up with MonInfo:

Code: [Select]

Monitor
  Model name............... Switchres
  Manufacturer............. SWR
  Plug and Play ID......... SWR0000
  Serial number............ Switchres#00
  Manufacture date......... 2005, ISO week 5
  Filter driver............ None
  -------------------------
  EDID revision............ 1.3
  Input signal type........ Analog 0.700,0.000 (0.7V p-p)
  Sync input support....... Separate, Composite (w. pulse)
  Display type............. RGB color
  Screen size.............. 480 x 360 mm (23.6 in)
  Power management......... Not supported
  Extension blocs.......... None
  -------------------------
  DDC/CI................... Supported
  MCCS revison............. 2.1
  Display technology....... TFT
  Controller............... Not specified
  Firmware revision........ Not supported
  Active power on time..... Not supported
  Power consumption........ Not supported
  Current frequency........ 16711.68kHz, 0.00Hz

Color characteristics
  Default color space...... Non-sRGB
  Display gamma............ 2.20
  Red chromaticity......... Rx 0.642 - Ry 0.349
  Green chromaticity....... Gx 0.292 - Gy 0.596
  Blue chromaticity........ Bx 0.147 - By 0.125
  White point (default).... Wx 0.313 - Wy 0.328
  Additional descriptors... None

Timing characteristics
  Horizontal scan range.... 15-16kHz
  Vertical scan range...... 49-65Hz
  Video bandwidth.......... 2550MHz
  CVT standard............. Not supported
  GTF standard............. Not supported
  Additional descriptors... None
  Preferred timing......... Yes
  Native/preferred timing.. 640x960i at 30Hz (4:3)
    Modeline............... "640x960" 13.000 640 664 728 832 960 964 976 1042 interlace -hsync -vsync

Standard timings supported

Report information
  Date generated........... 15/07/2014
  Software revision........ 2.90.0.1000
  Data source.............. Real-time 0x0300
  Operating system......... 6.1.7601.2.Service Pack 1

Raw data
  00,FF,FF,FF,FF,FF,FF,00,4E,F2,00,00,00,00,00,00,05,0F,01,03,6D,30,24,78,0A,5E,C0,A4,59,4A,98,25,
  20,50,54,00,00,00,01,01,01,01,01,01,01,01,01,01,01,01,01,01,01,01,14,05,80,C0,20,E0,29,10,18,40,
  26,00,E5,6C,11,00,00,98,00,00,00,FF,00,53,77,69,74,63,68,72,65,73,23,30,30,0A,00,00,00,FD,00,31,
  41,0F,10,FF,00,0A,20,20,20,20,20,20,00,00,00,FC,00,53,77,69,74,63,68,72,65,73,0A,20,20,20,00,AA

Here's the monitor.inf

Code: [Select]

; monsamp.INF
;
; Copyright (c) Microsoft Corporation.  All rights reserved.
;
; This is a generic INF file for overriding EDIDs
; of any monitors, starting with Windows Vista.
;

[Version]
signature="$WINDOWS NT$"
Class=Monitor
ClassGuid={4D36E96E-E325-11CE-BFC1-08002BE10318}
Provider="MS_EDID_OVERRIDE"
DriverVer=04/18/2006, 1.0.0.0

; Be sure to add the directive below with the proper catalog file after
; WHQL certification.
;CatalogFile=Sample.cat


[DestinationDirs]
DefaultDestDir=23

[SourceDisksNames]
1=%SourceDisksNames%

; Enable the following section to copy a monitor profile.
[SourceDisksFiles]
;profile1.icm=1

[Manufacturer]
%MS_EDID_OVERRIDE%=MS_EDID_OVERRIDE,NTx86,NTamd64

; Modify the hardware ID (MON1234) to match that of the monitor being used.
[MS_EDID_OVERRIDE.NTx86]
%MS_EDID_OVERRIDE-1%=MS_EDID_OVERRIDE-1.Install, MONITOR\SWITCHRES

; Modify the hardware ID (MON1234) to match that of the monitor being used.
[MS_EDID_OVERRIDE.NTamd64]
%MS_EDID_OVERRIDE-1%=MS_EDID_OVERRIDE-1.Install.NTamd64, MONITOR\SWITCHRES

[MS_EDID_OVERRIDE-1.Install.NTx86]
DelReg=DEL_CURRENT_REG
AddReg=MS_EDID_OVERRIDE-1.AddReg, 480, 640, DPMS
CopyFiles=MS_EDID_OVERRIDE-1.CopyFiles

[MS_EDID_OVERRIDE-1.Install.NTamd64]
DelReg=DEL_CURRENT_REG
AddReg=MS_EDID_OVERRIDE-1.AddReg, 480, 640, DPMS
CopyFiles=MS_EDID_OVERRIDE-1.CopyFiles

[MS_EDID_OVERRIDE-1.Install.NTx86.HW]
AddReg=MS_EDID_OVERRIDE-1_AddReg

[MS_EDID_OVERRIDE-1.Install.NTamd64.HW]
AddReg=MS_EDID_OVERRIDE-1_AddReg

[MS_EDID_OVERRIDE-1_AddReg]
HKR,EDID_OVERRIDE,"0",0x01,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x4E,\
0xF2,0x00,0x00,0x00,0x00,0x00,0x00,0x05,0x0F,0x01,0x03,0x6D,0x30,0x24,\
0x78,0x0A,0x5E,0xC0,0xA4,0x59,0x4A,0x98,0x25,0x20,0x50,0x54,0x00,0x00,\
0x00,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,\
0x01,0x01,0x01,0x14,0x05,0x80,0xC0,0x20,0xE0,0x29,0x10,0x18,0x40,0x26,\
0x00,0xE5,0x6C,0x11,0x00,0x00,0x98,0x00,0x00,0x00,0xFF,0x00,0x53,0x77,\
0x69,0x74,0x63,0x68,0x72,0x65,0x73,0x23,0x30,0x30,0x0A,0x00,0x00,0x00,\
0xFD,0x00,0x31,0x41,0x0F,0x10,0xFF,0x00,0x0A,0x20,0x20,0x20,0x20,0x20,\
0x20,0x00,0x00,0x00,0xFC,0x00,0x53,0x77,0x69,0x74,0x63,0x68,0x72,0x65,\
0x73,0x0A,0x20,0x20,0x20,0x00,0xAA

[DEL_CURRENT_REG]
HKR,MODES
HKR,,MaxResolution
HKR,,DPMS
HKR,,ICMProfile

; Pre-defined AddReg sections. These can be used for default settings
; when a given standard resolution is used.

[640]
HKR,,MaxResolution,,"640,480"

[DPMS]
HKR,,DPMS,,1

[MS_EDID_OVERRIDE-1.AddReg]
HKR,"MODES\640,480",Mode1,,"15.75-15.75,60.0-60.0,+,+"

; Enable the following section to copy a monitor profile.
[MS_EDID_OVERRIDE-1.CopyFiles]
;PROFILE1.ICM

[Strings]
MonitorClassName="Monitor"
SourceDisksNames="MS_EDID_OVERRIDE Monitor EDID Override Installation Disk"

MS_EDID_OVERRIDE="MS_EDID_OVERRIDE"
MS_EDID_OVERRIDE-1="SwitchRes"
Note that I had to lead the binary with 0x01 when creating the registry entries - it wasn't just a matter of dumping it in exactly.

I've actually got the DVI-D connection running at what I believe is 640x960 interlaced (i.e. there's some weirdness with the settings). The monitor is complaining it's out of sync and "List All Modes" only shows interlaced resolutions at 14/15hz

[cools]

Using MonInfo I was able to edit the EDID so that Windows was happier with it and it actually displayed the correct interlaced modes:

Code: [Select]

; INF file generated by Monitor Asset Manager (2.90.0.1000), 15/07/2014
; Copyright (c) 1995-2014, EnTech Taiwan.
; Internet: http://www.entechtaiwan.com

[Version]
Signature="$WINDOWS NT$"
Class=Monitor
ClassGUID={4d36e96e-e325-11ce-bfc1-08002be10318}
Provider=%MFG%
DriverVer=15/07/2014, 1.0.0.0
;CatalogFile=YourSignedCatalogFile.cat

[DestinationDirs]
DefaultDestDir=23

[SourceDisksNames]
1=%DISC%

[SourceDisksFiles]
;YourColorProfileFile.icm

[Manufacturer]
%VENDOR%=EDID_OVERRIDE,NTx86,NTamd64

[EDID_OVERRIDE.NTx86]
%PRODUCTID%=OVERRIDDEN-EDID.Install, MONITOR\SWR0000

[EDID_OVERRIDE.NTamd64]
%PRODUCTID%=OVERRIDDEN-EDID.Install.NTamd64, MONITOR\SWR0000

[OVERRIDDEN-EDID.Install.NTx86]
DelReg=DEL_CURRENT_REG
AddReg=OVERRIDDEN-EDID.AddReg, MODE1, DPMS
CopyFiles=OVERRIDDEN-EDID.CopyFiles

[OVERRIDDEN-EDID.Install.NTamd64]
DelReg=DEL_CURRENT_REG
AddReg=OVERRIDDEN-EDID.AddReg, MODE1, DPMS
CopyFiles=OVERRIDDEN-EDID.CopyFiles

[OVERRIDDEN-EDID.Install.NTx86.HW]
AddReg=OVERRIDDEN-EDID_AddReg

[OVERRIDDEN-EDID.Install.NTamd64.HW]
AddReg=OVERRIDDEN-EDID_AddReg

[OVERRIDDEN-EDID_AddReg]
;Base EDID
HKR,EDID_OVERRIDE,"0",0x01,0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x4E,0xF2,0x00,0x00,0x00,0x00,0x00,0x00,0x05,0x0F,0x01,0x04,0x6D,0x30,0x24,0x78,0x0A,0x5E,0xC0,0xA4,0x59,0x4A,0x98,0x25,0x20,0x50,0x54,0x00,0x00,0x00,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0xD0,0x04,0x80,0x90,0x20,0xF0,0x16,0x00,0x08,0x3A,0x13,0x00,0xE0,0x68,0x11,0x00,0x00,0xA0,0x00,0x00,0x00,0xFF,0x00,0x53,0x77,0x69,0x74,0x63,0x68,0x72,0x65,0x73,0x23,0x30,0x30,0x0A,0x00,0x00,0x00,0xFD,0x00,0x31,0x41,0x0F,0x10,0xFF,0x00,0x0A,0x20,0x20,0x20,0x20,0x20,0x20,0x00,0x00,0x00,0xFC,0x00,0x53,0x77,0x69,0x74,0x63,0x68,0x72,0x65,0x73,0x0A,0x20,0x20,0x20,0x00,0x5B

[DEL_CURRENT_REG]
HKR,MODES
HKR,EDID_OVERRIDE
HKR,,MaxResolution
HKR,,PreferredMode
HKR,,DPMS
HKR,,ICMProfile

[DPMS]
HKR,,DPMS,,0

HKR,,PreferredMode,,"640,480,30"
[MODE1]
HKR,,MaxResolution,,"640,480,30"

[OVERRIDDEN-EDID.AddReg]
HKR,"MODES\640,480,30",Mode1,,"15.0-16.0,49.0-65.0,+,+"

[OVERRIDDEN-EDID.CopyFiles]
;YourColorProfileFile.icm for non-sRGB displays

[Strings]
MFG="EnTech Taiwan"
DISC="Monitor EDID Override Installation Disk"
PRODUCTID="SWR Switchres (SWR0000 EDID Override)"
VENDOR="SWR"


However the NVidia driver/chip/laptop I'm running off won't drop to that resolution (using the VGA out and forcing the monitor over the "non-pnp" driver, on an old Sony PVM.

I still need to try with a non-interlaced resolution but I've a feeling i'm hitting driver limits.

[Calamity]

Using MonInfo I was able to edit the EDID so that Windows was happier with it and it actually displayed the correct interlaced modes:

Remind I said the EDID specification was fuzzy about interlaced modes? I had a problem when adding the EDID code to Switchres. If I entered the actual vertical values for interlaced modes, then MonInfo said the resolution was 960i instead of 480i. Only if I divided the vertical values by 2 then MonInfo was happy and showed the proper modeline. But doing so made Linux ATI drivers show a double picture: odd field up and even field down. When entering the values without dividing, it worked fine. However, MonInfo showed the wrong resolution.

I'd like to think that Linux ATI drivers are doing the right thing although I'm not sure any more. If Windows drivers actually want the halved values then we'll need OS-specific EDIDs, it's ironic. The problem is not only halving the values. The problem is you loose precision by doing so, because all vertical values become even numbers.

Anyway can you explain what you needed to change exactly to make the intelaced modes work?

[cools]

Using MonInfo I was able to edit the EDID so that Windows was happier with it and it actually displayed the correct interlaced modes:

Remind I said the EDID specification was fuzzy about interlaced modes? I had a problem when adding the EDID code to Switchres. If I entered the actual vertical values for interlaced modes, then MonInfo said the resolution was 960i instead of 480i. Only if I divided the vertical values by 2 then MonInfo was happy and showed the proper modeline. But doing so made Linux ATI drivers show a double picture: odd field up and even field down. When entering the values without dividing, it worked fine. However, MonInfo showed the wrong resolution.

I'd like to think that Linux ATI drivers are doing the right thing although I'm not sure any more. If Windows drivers actually want the halved values then we'll need OS-specific EDIDs, it's ironic. The problem is not only halving the values. The problem is you loose precision by doing so, because all vertical values become even numbers.

Anyway can you explain what you needed to change exactly to make the intelaced modes work?

Both EDIDs showed interlaced modes in the mode list, but moninfo generated them without doubling the vertical. This is on an nvidia chip and a laptop, so I expected weird behaviour.

To generate the file with moninfo I simply pasted the desired modeline into the required resolution box and saved the inf.

I'll have a go on the cab now. Give me ten minutes.

[cools]

On the cab (CRT_Emudriver), not such encouraging results.

MonInfo requires a starting point. I'm not sure the starting point I'm using is suitable.

The Toshiba gives no EDID information whatsoever that can be read by MonInfo. So, I load my initial monitor override inf (with SwitchRes arcade_15 EDID data), reboot and I'm in 640x480 progressive. I can then use MonInfo to load the registry data (it's not able to load the inf I've created directly), insert the 640x480i modeline, create another inf file, load this one up and reboot again. Now 704x480.

With either inf file I lose ALL interlaced custom modes from ArcadeOSD, and Windows as well. The "recommended" resolution for the monitor gets set to 640x960 and 704x480 respectively.

Definitely seems to be an avenue worth pursuing. Don't have time today to keep playing around, but I did just give this a try: http://www.lightware.eu/index.php/support/downloads/667-advanced-edid-editor-software - allows creating EDID data for free.

[Calamity]

I see. The problem is probably that Win ATI drivers are ignoring the EDID when the ranges are "unusual" (15 kHz). Probably the same reason why the EDID dongle doesn't work with ATI.

In the first case, and because the EDID created by Switchres doesn't have the vertical values halved, the modeline is assumed to be 31kHz/30i Hz, which is out of range (vfreq), so it's simply discarded. But as you provide a valid maximum resolution of 640 x 480 in the .inf, this one is used but with a default VESA timing.

In the second case, once the vertical values are halved by MonInfo, the modeline is properly read as 15kHz/60i Hz, which is out of range too (hfreq this time, Win ATI drivers don't seem to like 15 kHz EDIDs). So it's discarded again. And for some reason 704x480 is chosen.

I bet that 31kHz/60i would be accepted.

This also makes me wonder if the Linux ATI drivers are managing the interlaced modes right when reading from the EDID. Not only MonInfo, but also one specs sheet I read somewhere pointed to using halved values for interlaced modes. I'd really hate the idea...

[Calamity]

You can try replacing these lines in SwitchRes edid.c:

Code: [Select]

int v_active = mode->vactive / mode->interlace?2:1;
int v_blank = ((int)mode->vtotal - mode->vactive) / mode->interlace?2:1;
int v_offset = (mode->vbegin - mode->vactive) / mode->interlace?2:1;
int v_pulse = (mode->vend - mode->vbegin) / mode->interlace?2:1;

(haven't tested this)

[cools]

Playing around with the Lightware tool highlighted the half vertical resolution as well. Its a little strange to use (if you use the wizard it embeds information you can't edit anywhere, yet its happy enough working from empty).

Will try some more soon

[cools]

Did some more playing around with 15KHz EDIDs and the Nvidia driver today. Unsuccessfully. Important if anyone else is playing around, you need to have a method of accessing Windows without a monitor, as if you override the EDID there's no practical way of getting in and removing the settings without registry access or being able to uninstall the monitor inf. The registry access is difficult due to SYSTEM permissions, and removing the inf requires the monitor to be connected while you're doing it...

[Calamity]

Hi Cools,

Thanks for sharing your results. I think I should to move these posts about EDID tests and the ones in the GroovyArcade thread into a thread about custom EDIDs, what do you think?

[lodoss118]

Any luck on this

[cools]

That'd make sense.