945G s-video out. X vsync / refresh rate error? Let me buy you lunch
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945G s-video out. X vsync / refresh rate error? Let me buy you lunch
UPDATE: This is on the d945gclf2 mini-itx board.
Upon power on, the system bios/video bios takes care of everything and the s-video out to TV is fine(60hz refresh rate, etc). But when linux takes over, the VGA signal from the 945G going to the decoder (ch7021) has a refresh rate of 100 Hz. Then the decoder (ch7021a) sends this out to the TV via the s-video connecter at 60hz. So there is an over-layed 100hz screen on a 60hz signal. This is where the rolling comes in.
...this only happens after the linux driver takes control of the video hardware.
:END UPDATE
I'll gladly buy someone lunch if they can figure this one out (paypal?)
- intrepid 8.10
I recently got a mini-itx motherboard with integrated intel 945G graphics. I have it plugged into my tv through the s-video. Upon boot-up,everything is fine, even during the 'ubuntu' loading screen (where the status bar goes across the screen) is fine. But upon going into X, it's like the refresh rate gets lost, and the screen just rolls like there's a vertical sync problem. I've googled the heck out of this and no luck. The colors are all fine, it's just that it's rolling... or perhaps a refresh rate problem. xrandr says it's at ~60hz in ntsc-m mode. All other computers work fine with the setup. it's just this particular unit that I have that doesn't. VGA is fine.
Again, I'll be glad to buy you lunch... I'll just send a 10 bill your way... somehow... paypal, etc. That's a pretty good lunch..
I've tried all resolutions. This is on an intel atom 330 board - the D945GCLF2
UPDATE: I've been comparing the signals (on my oscilloscope) between the working and non-working conditions. There's something being written to the TV out chip (ch7021) (between the s-video connector and the 945G chip), and it seems as though there are two sync blanking being muxed together. One is the 60hz, the other is xxhz. I'm digging into the data sheets now.
Also, apparently, there is a ch7017 header file in the LinuxIntelDrivers... also a ch7xxx header file. This board uses the ch7021. I'm going to put an analyzer on the I2C bus on monday, to see if the driver writes anything different than what gets written at power on.
This board was released in september '08. I don't know if this combo vid and s-vid decoder was ever married before on other platforms. Hopefully someone will chime in with their 8.10 setup and let me know.
Last edited by MikeOfAustin; 11-23-2008 at 08:34 PM.
Have you tried different refresh rates? (System->Preferences->Screen Resolution)?
I'm not using the same setup as you, but I do have integrated Intel graphics chips. The default refresh rate of 60 Hz left my display grainy with a background flicker on my monitor. Setting it to 75 Hz cleared up everything.
So here's what's going on with the s-video signal... Upon power on, the system bios/video bios takes care of everything and the s-video out to TV is fine(60hz refresh rate, etc). But when linux takes over, the VGA signal from the 945G going to the decoder (ch7021) has a refresh rate of 100 Hz. Then the decoder (ch7021a) sends this out to the TV via the s-video connecter at 60hz. So there is an over-layed 100hz screen on a 60hz signal. This is where the rolling comes in.
...this only happens after the linux driver takes control of the video hardware.
I was monitoring the I2C data going to the decoder. Data is written to the ch7021 every time the screen changes modes during the system boot process. The system (not linux drivers), writes to common addresses in the ch7021a... (0x03, 0X04, 0X07, ETC). And it's usually only 4 or so addresss that get written. But when the linux driver takes over, a whole slew of stuff gets piped out to addresses in the part that weren't previously written (0x1,0x2,0x5).
I need to get my old I2C probe working again to be able to capture any meaningful data (instead of walking bits with my finger on a logic analyzer screen).
I've linked some photos (excuse the old school tech. This is at home).
Here are some photos of my findings. You'll notice the 60hz (when everything is fine), then the 100hz after linux drivers take over, and finally, the pic of the TV screen that's rolling.
I seem to have the same problem and haven't found an answer yet. I have been trying to use xrandr to change refresh rates but haven't had any success with that either.
Keep on posting if you find a solution.
Has anyone to s-video working on this board under ubuntu?
I found other people having the same problem at the linuxmce forum. Basically, if you use module i810 instead of i915 (8.04?), it'll run in vesa mode(?) because there's no acceration, and it you use mplayer to play a video, the video goes back to rolling again, and you have to reboot. I sent a message to intel support regarding this issue and product. Note, that they're sending out bios update all the time, (as recently as last week), so they must still be working on the board (got it out the door without fully testing it).
I wouldn't of bought the board if I knew s-video didn't work (it's useless without a vga monitor). It says right on their web site that it does work.
Last edited by MikeOfAustin; 12-03-2008 at 06:02 PM.
Well you should know that intel graphics chipsets, as was succinctly stated by someone on digg, are worth their weight in guano. In some parts of the world that may be a lot, but not here.
We got the newest drivers from the git repository and they didn't help either. Need to wait for someone that can change the code, I'm not a software guy either.
One thing we noticed. We used a couple of different VGA monitors and each one had a different default resolution. If we set the TV-1 output to the same resolution the picture would almost lock. Instead of seeing the fast rolling it was very slow. Not sure if that means anything.
Note that there are two values you can change to try to fix it: HorizSync and VertRefresh both in the "Monitor" section of your 'xorg.conf'. I would try changing those to the right values. I would also use the vesa drivers.
You say
Quote:
Upon power on, the system bios/video bios takes care of everything and the s-video out to TV is fine(60hz refresh rate, etc). But when linux takes over, the VGA signal from the 945G going to the decoder (ch7021) has a refresh rate of 100 Hz.
What do you mean by "when linux takes over", is this before or after X starts up ? On Ubuntu this may be hard to know, because it usually boots straight into graphical mode.
Also, for what it's worth, I've been on the driver-intel list and this is a known bug. It has to do with communications not implemented for the SDVO mode in the Chrontel s-video chip. There is rumor that this will be fixed with the next release of the driver.
Hopefully, one of the programmers will claim his lunch sooner, rather than later
I don't know if this is relevant to your problem, but I can only get the intel dirver to work on my 945G system if I edit the xorg.conf file to look like this:
My problem is that the monitor I'm using seems to fails to communicate with the intel driver so the "automatic" modline settings are not correct.
F.Y.I.: The problem is so bad that, when I installed Fedora 10 from the DVD, I initially got a "black screen," and had to do a "linux text" install, and use the vesa driver. Interestingly, the vesa driver correctly identified the modline settings, and I just did a cut-and-paste from the log file to the xorg.conf file.
F.Y.I. 2: The new 945G driver for Vista has the same problem, and upgrading my Vista to the newer driver yields the same "black screen" in Vista. (I have a multi-boot system that came with Vista pre-installed.)
I have the intel D945GCLF2 atom board, and I can't get the svideo out working. According to myth wiki, the xorg.conf does not control the tv-out ports, and the modes are hardcoded. Did anyone manage to get ch7021 decoder working?
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