Flickering image on Bang Olufsen TV

[bluetrain]

Iīm a bit puzzled so maybe you guys can help me out.

Some month ago I bought a Bang Olufsen MX8000 tv (4:3 tube tv with scart only) . As I didnīt have desktop pc at the moment I hooked it up to an old xbox with a rgb scart and it works pretty good. However my goal was always to use a desktop with a ATi card and groovymame to get that flawless emulation.

Said and done I got a desktop PC with an ATI HD5770 Silent (fanless) and a SCART adapter. The UMSA from arcade forge http://arcadeforge.net/UMSA:::15.html?MODsid=1d2eab7959cb8082b51bef3952c26736. So I hooked up a scart from the tv to the adapter and then a vga from the adapter to DVI on graphics card (as it has no vga).

I burned a groovymame live cd (the latest) and the picture just flickers in the menu. I tried both standard arcade (15,7khz) and pal tv but flickers anyway. Iīm not sure what mode I choose
but somehow when pressing buttons random I manage to start a game and then the picture was ok!

Any clues what to do?

[Calamity]

Any clues what to do?

Try Windows 7. It adds bilinear filtering (blurriness for some) to interlaced modes, reducing flicker a big amount.

[bluetrain]

Thanks Calamity! I will try that. However just for the record its no small flicker, more out of sync. Like this.

[Calamity]

Flicker? That's Jupiter man.

[bluetrain]

Haha yeah... well that was the best I could find... Anyway. I tried with win7 (and your drivers of course) and when I tried to lower resolution to lets say something like 200x300 at 60hz it shows that on the lcd-monitor. So I guess the crt driver is working then? When I unhook and reconnect to the tv its the out of sync show as you can see below. Could it somehow be driver related?

[Calamity]

It sounds like GA is sending the signal to the wrong output (or if you prefer, the DVI adapter is plugged in the wrong output).

[bluetrain]

Hi,

I didnīt solve the issue but will give it a new try with some new approach and info.


So my graphics card has 1 dvi, 1 hdmi, 1 display port. I figured that analog signal must come from the dvi port. I hooked up a dvi to vga cable.

I have installed the latest crm emu driver (crimson) for win 10 successfully and vmmaker. When I choose a 15,7khz res (on my lcd) the monitor goes out of signal and when I hook it up
to the scart/vga adapter (umsa) it still flickers. Itīs better than the picture but clearly out of sync. I bought at cheap scart/vga adapter from china and when I hook it upp it works using for example 800x600, 1024x768 at 60hz but this was only for test purpose..


What is the best approach to trouble shoot?

1) A cable issue? either the vga/dvi cable or the scart cable (has full pins and works in other configurations). The cables are working but perhaps not with this tv? Or should I try the hdmi port instead of the dvi?
2) Graphics card, should I try another one?
3) Television has problem accepting the signal? (for the record. I have an original modded xbox with mame connected via component/scart and it looks really nice)
4) Something else??


Would really appreciate if someone could help me solve this mystery and I can move on some playing at 15khz

[buttersoft]

I hooked up a dvi to vga cable.

I have installed the latest crm emu driver (crimson) for win 10 successfully and vmmaker. When I choose a 15,7khz res (on my lcd) the monitor goes out of signal

OK, i stopped reading right there. If you install crt_emudriver on Windows 7 with a 5770 you should *not* be using an LCD on the same port. With your card you want to enable the EDID emulation in VMM. After that, no LCD via DVI-I/VGA, as the desktop should be in 480i. Some LCD's will handle 480i, but either way...

First, make sure you have the right version of crt_emudriver for your card. Read this post - http://geedorah.com/eiusdemmodi/forum/viewtopic.php?id=295

Next, check out the guide on Calamity's site for the Radeon HD 5450, which applies to any 5000 series card or newer. Make sure to follow it exactly Then you use the DVI-to-VGA adapter, vga cable to USMA, then SCART to the TV. You want the USMA to pass the image straight through and only combine syncs, not alter anything else. IIRC it's fine to do that.

This is the setup guide for your card - http://geedorah.com/eiusdemmodi/forum/viewtopic.php?id=301

This configuration is the simplest one, get this working first. Start with a fresh install of Windows if you can.

[bluetrain]

Thanks so much for pointing me in the right direction! Does it matter if I choose windows 7 instead of win 10 when doing fresh install?

One thing I still wonder. Shouldnīt the display be correct when booting into the groovy mame live cd since I can choose the resolution/freq (15khz) in the start menu?


Edit: reason why Iīm asking is that if itīs not working with the live cd, perhaps the UMSA is broken?

[Calamity]

As I said in February the GA live cd issue is probably because output was mapped to the wrong connector from the boot menu. Did you try different combinations?

[bluetrain]

As I said in February the GA live cd issue is probably because output was mapped to the wrong connector from the boot menu. Did you try different combinations?

Yeah I tried the other outputs (hdmi and displayport, to vga-adapter) but that didnīt solve it.

[Calamity]

Yeah I tried the other outputs (hdmi and displayport, to vga-adapter) but that didnīt solve it.

I'm not sure if we're talking about the same thing. I meant the output configurations from the live CD boot menu. Iirc, you have DVI-0, DVI-1, VGA-0, VGA-1, etc.

But GA and CRT Emudriver output quite standard signals. I see no reason why your B&O should not sync, specially if you use an UMSA, which already deals with the sync mix and polarity issue that is the problem in 90% of cases.

[bluetrain]

Thanks for your reply! Yeah I tried all the options in the menu (dvi 0, dvi 1, vga 1, 0 etc..) but nothing solved it..
However, when using the live cd I also tried the 50/60hz option with another scart/vga adapter that I bought from china, https://www.ebay.com/itm/152656200103
and that thing showed the game menu correctly (because displaying at 60hz?) but when choosing a game it was a rolling picture

[bluetrain]

After a lot of headache and giving up a couple of times I have finally found a solution that may be helpful to others: I switched the tv to a sony trinitron and now groovymame works flawless! Playing on a crt with full speed, no tearing or lag is such a delight!

After a lot of reading I understand that somehow the wiring for the scart in the bang olufsen mx8000 must be different. Is it the sync? I donīt know if it is possible to re-wire but if you donīt have that knowledge, donīt waste time on the b & o like I did! Just use a sony trinitron and you will be just fine

[Nipedley]

Just wanted to chime in here, not able to help with your issue but I'm using a B&O MX4000 perfectly with CRT Emudriver 2.0 Beta 11

Did you try the sync polarity option on the UMSA ? Not sure what info you found regarding the scart, but the Bang and olufsen MX4000 worked fine for me using the default sync polarity with the UMSA

[bluetrain]

Yeah I tried the sync option but to no avail. I also tried other cables and it worked with no problems with other consoles hooked up with rgb scart. I guess sometimes you just have to realize your technical limits and move on. While the mx8000 no doubt was a good tv I was pretty much blown away by the quality of the trinitron, the sharpness and colors are I think are on the next level compared to the mx8000 which had a pretty "soft" image so all in all it worked out pretty good

[retrorepair]

I had the same issue with my mx7000, it was down to the sync in the end. It's a bit pickier than your average monitor.
Are you just soldering H/V sync together? Try this:



It isn't the best way to combine syncs but worked for me.

Also make sure you are sending 5v to blanking on the scart connector.

[Calamity]

It's odd because bluetrain is using an UMSA which should already be outputting a proper c-sync. Another thing he might consider trying is the new c-sync feature in VMMaker.

[retrorepair]

C-sync feature? I've not noticed that.

What does the UMSA do to combine sync? Use a 74HC86?