Emulation PC through CRT (Newbie Alert!)

[Sam250]

Hello all!— lovely forum you have here.

I want to play emulated games (mainly of MAME, but certainly others too) through a CRT. For you this will be a boringly straightforward project, but it is new to me and I would like to get things right, so I am looking generally for advice, education, correction ect. So, I’ll describe what I am doing and what I understand of the process, and I hope some of our can offer your expertise.

Though I have done research, no doubt there is a wealth of information on sites am yet to stumble upon, and more buried in older threads of this forum, so any links to other completed projects, or guides and q and a’s would be great to see. Post what you've got!

If this is the wrong place for this, I apologise. I know this is a forum about arcade cabinets, and a subforum for GroovyMAME, to which this is only tangentially related. But this is the praise I heard from SCART Hunter:

The GroovyMAME forum has become the ultimate destination for those seeking emulation perfection using a CRT. Some excellent technical information scattered throughout and the members are most helpful.

Okay: first thing I’ll need is a TV.  Somebody near me has two CRTs for sale:
http://needmanuals.com/PANASONIC/TX28MK1/instructions
http://www.sony.co.uk/support/en/product/KV-21LT1U
I’ve heard good things about both brands, and especially Trinitron. Both have SCART, which as I understand is a great choice in terms of quality.

This’ll go into a PC via VGA to SCART, both of which transmit RGB signals, which I can do either by modifying a VGA cable with a SCART connector and a soldering iron (as alvarezeninternet.com/mamescart/), or buy a converter box (I’m curious about trying a soldering iron for the first time myself).

The new PC is just going to be powerful enough to play MAME and emulators of consoles up to the 5th generation, so I am thinking: Windows XP, 1GB or 2GB RAM, 2Ghz processor, 50GB HDD, and I guess an ATI Radeon graphics card to take advantage of CPUEmu (any suggestions?).

Video out from the PC needs to be adjusted by way of CRT Emu, AdvanceMAME, GroovyMAME, Soft-15khz, or similar software. This will reduce refresh rate to speeds manageable by the CRT, and reduce the resolution to the native resolution of the games so... it displays correctly I guess?

Then it is just a matter of launching Mala, or whatever, and bask the sublime glow of DoDonPachi in phosphor dots.

Now, though still looking for all general feedback, some specific questions:

1. I hear the word “modeline” often and think I get the general idea, but is it a concept I am going to have to put to work in this project? How and why?
2. I haven’t looked much into audio. Is it just a matter of a 3.5mm from PC to RCA into the front of the TV? Are there better options?

There may be more questions as they come to me.

Thanks for reading!

[Calamity]

Hi Sam250,

Well, setting up a pc to properly output video to a SCART TV is NOT a straightforward process for any of us, you always stumble upon unexpected problems even if you are experienced, but anyway that's part of the fun. Let's say that outputting a 15 kHz signal is just the beginning.

As for the TVs you linked, I'd follow the Paradroid's Philosophy: go and pick both of them, so you can compare.

If I were you, I'd wouldn't bother soldering, it's up to you to decide if you've got the skills, but bear in mind that a badly built cable can cause a lot of headaches to you, specially at the beginning, when you don't know if the issues are hardware or software related. I'd just buy this: http://scarthunter.blogspot.com.au/2012/06/umsa-ultimate-scart-adapter-review.html

The PC: don't underestimate the CPU requirements for a MAME pc, you're going to need the most powerful CPU you can afford, especially if you don't want to upgrade it for a couple of years. Search the whole forum and check what kind of PCs the experienced users here are building.

My advice is to use a dedicated pc for MAME, with a Radeon X600 card. Use a different PC for 5th generation consoles. If you really really really can't live without running those on the same PC, then buy a Radeon HD 4890 card instead.

Regarding the software side, here we're using CRT Emudriver but that's just one the possibilities, not the easiest for a beginner. If you have no experience, I'd start with Soft-15kHz. Check this thread: http://forum.arcadecontrols.com/index.php?topic=119768.0

You don't really need to know what a modeline is in order to get any of these software working, they do it for you. At some point, you may discover the logic behind the modeline concept, after all it's just primary school arithmetics, and how it's related to the way a CRT works.

If you're using the SCART input, you should get the audio through it, that's the right way unless you want to use external loudspeakers.

Good luck!

[Sam250]

Many thanks for the reply Calamity. I'll be following your advice on both the SCART adaptor and Soft-15khz.

I don't really understand the logic behind keeping MAME emulation and the consoles emulation separate. Isn't it just a matter of building a machine powerful enough to handle each of them? Does the exclusivity apply to all consoles, or only more advanced ones (ie. what about SNES and MAME on the same computer)? Why in particular the difference in graphics cards? I am definitely eager to have my emulators in the same place, so it would be great to hear more on this topic. At any rate I will look into what other users are doing as you suggest and see if I can work it out.

[Calamity]

MAME doesn't require a fancy video card, all is software rendered, thus you can use an older Radeon like the X300 or X600, which are the ones that work the best for custom video, while they are still PCIe, so they will work on the most modern and powerful motherboard.

On the other hand, other emulators for consoles like Dreamcast rely on the hardware acceleration on the video card's chipset. So you need something more powerful, like the HD4xxx family, especially the high-end models. Those are the most modern cards that fully support the kind of custom video we're doing here. They are great, no problem with them, but some subtle details make me prefer the older Radeons.

What I meant is that some people make a lot of compromises on their setup just to be able to run some specific emulator, or modern games like SF IV, which at the end of the day are not so important compared to what MAME offers. But this is just my opinion. Make a planning of the systems you're going to emulate and see the system requirements for each one.

I'm not telling you to rennounce to all consoloes, SNES and Genesis and others can be emulated quite well by UME (a combined build of MAME and MESS).

[Sam250]

Okay, great, I'm understanding you now. In that case I'll probably stick with an older Radeon. Thanks again for your help. I'll post an update when I am working on it or finished (or, likely, stuck).

[Sam250]

I do now have a MAME emulation computer running through a CRT, and it looks pretty good so far. I have just a few problems that I haven't found any solutions to online:

1. Service mode. I'm wanting to correct some considerable overscan, but I simply cannot seem to get access to the service mode. The service manual tell me to press i, then 5, then volume-up, then TV on, whilst in standby. Well that does nothing at all, including turn on the TV at any point.. So I press the on button again, the TV turns on, but there is no TT indicating test mode. The buttons all work perfectly when the TV is on. My TV is a Sony Trinitron KV-21FT1E. I think I got the service manual from here. Am I doing something wrong? Any thoughts?

2. Horizontal centering. None of the options for H center in ArcadeVGA give me a satisfactory position. The closest options leave me with a considerable black bar down the left or right of the screen. I'm guessing this can also be corrected in service mode also.

3. Frontend for GroovyMAME. I find it a real pain to navigate a tiny interlaced resolution of Windows with a keyboard to get to my games.  Ideally something  like Mala, which I could not get to work with GroovyMAME (I may just be being stupid, as I'm sure I've read about other people here using it. I'll try again once I get home). I'm looking into AdvMenu as we speak. What does everyone else here use?

I'll post some pictures this evening.

[Calamity]

Hi Sam250,

1. You'll probably have better luck asking on the Monitor/Video section.

2. Do you mean with the Arcade Perfect utility?

3. I personally keep using AdvMenu for virility reasons, but any frontend that works with MAME should work with GM just the same. There's a problem however with the last version, due to the way that some frontends retrieve the version of MAME they're getting fooled by GM, but this will be solved in next version.

[apfelanni]

tv in standby > i+ > 5  > vol+ >  tv should do the trick  .. chassis is fe-2 . maybe u type in to fast or to slow . or ure pressing the wrong buttons .. hor size and pos can be changed in osd. i upped the manual , in case u dont have the right one .

http://www.share-online.biz/dl/69JVCTHM6T

[Sam250]

Whoops: by ArcageVGA I meant Arcade_OSD.

[Calamity]

Ah ok.

Be aware that when using GM, the centering you do with Arcade_OSD will be overridden by GM's own geometry settings, so it only makes sense to do it as a way to get the right values and use them as input when creating a custom crt_range for GM.

That said, getting low horizontal resolutions (e.g. 256x224) perfectly centered can be impossible: the granularity is just not enough. You usually will start with a higher horizontal resolution to get more accurate values in order to build your crt_range from.

Finally, you can use a trick in GM consisting in doubling low horizontal resolutions, by setting 'dotclock_min 8.0' option, this will give more accurate centering for lower resolutions.

[Sam250]

Thanks as always, Calamity, and you, apfelanni, I'll see where this gets me.

[Sam250]

Just a link to the Monitor/Video forum thread in which I resolve some of the above problems:

http://forum.arcadecontrols.com/index.php/topic,130338.0.html

Next for me is getting a front-end working.

[Sam250]

Agh, what is going on: I turned on my emulation PC the other day and got a black screen on my TV. Plugged PC into a monitor, and found all my extra resolutions had disappeared. Reinstalled CRT_Emudriver 6.5, ran VMMaker, all modelines seemingly restored, except all listed as gray "native" resolutions on Arcade_OSD. Restarted computer, and all resolutions gone again. Now when I run VMMaker, this is what it reads:

-------------------------------------------------------------
:: VideoModeMaker :: - version 1.3 - por Calamity - 2008/2011
-------------------------------------------------------------
monitor_specs line ignored
CRT_EmuDriver 1.2 found! Based on Catalyst 06.11

Extracting mame.xml...

Mame v0.148 (Jan 11 2013)

Importing video modes from Mame.xml...

 18 different video modes found.

Generating dynamic mode table... 17 redundant video modes found.
Reducing mode list... 0 video modes dropped.
 1 modelines generated.

Storing modelines in system registry...
System must be restarted for the changes to take effect.


Finished. Press any key...

[Calamity]

Get the latest version of VMMaker (1.3c), they changed the XML format in recent MAME versions, so the update is necessary:

http://mame.3feetunder.com/windows-ati-crt-emudriver/

[rCadeGaming]

HD4xxx family... They are great, no problem with them, but some subtle details make me prefer the older Radeons.

Could you elaborate on what subtle details you mean?

[Calamity]

HD4xxx family... They are great, no problem with them, but some subtle details make me prefer the older Radeons.

Could you elaborate on what subtle details you mean?

Well, the HD4xxx family is perfect for 15 kHz output (just as good as older Radeons), and is the only alternative if you require some GPU power. The subtle details I mean are:

- HD4xxx BIOS modes look worse (virtually unreadable) through a J-PAC than older Radeons did (split screen but clear video). This is unconvenient and may require to have a PC monitor around when you need to tweak things on boot.

- HD4xxx will leave only its primary output "open" when it doesn't sense any monitor (the case with arcade monitors which are not detected). You can enable the secondary output from Display Properties, but the change will be lost on restart. Thus, you can't use these cards to have 2 arcade monitors attached permanently unless you re-enable the secondary output on each session. This is not the case with older Radeons.

- HD4xxx's primary output is on the DVI port, most of the time. So you'll need a DVI-VGA adapter (no big deal).

- Some users reported that older Radeons produce better looking interlaced modes than HD4xxx.

When I say "older radeons" I'm specifically thinking on X300-X600 cards.

So as you see, they are in no way critical detais, but if you don't need GPU power because you only use MAME/UME, as is my case, the older radeons are somewhat more convenient and they are PCIe so you can stick them in any up-to-date board.

[rCadeGaming]

Thanks for the quick reply.

I'm using an ASUS PCIe HD4350, the one I linked to in the other thread with a VGA, DVI, and HDMI output:

-Yes, the BIOS screens are total gibberish when connected to my 15kHz TV.  Also, my Extron Super Emotia won't sync up to its output during BIOS, so I guess it's not exactly 480p?  So yes, separate monitor required for BIOS adjustments, although the need will be super rare.

-Haven't tried dual monitors, so no idea...  Could you get the card to think it detects a monitor with 75ohm resistors from the RGB lines to ground, or does it need something on the monitor ID pins?  If the latter, could you fool them with something simple like a connection to ground or a certain voltage or something?

-I'm not sure if the VGA port is the "primary output," but it seems to start up on it as long it has a 75ohm termination.

-The interlaced output looks really nice in games (desktop is flickery crap of course).  I don't have another card to compare with, but it looks at least as good as a PS3.

[Sam250]

Been meaning to get some photos up here for weeks. Still some issues, but I've completed Super Mario Bros. and Metroid and played a whole bunch of arcade games on this thing so I'm not unhappy with it. Any thoughts for improvement would be welcome.

Main annoyance is was screen tearing. It's only on USA roms of NES games, visible in the Castlevania pic. A screen tear travels up the screen every few seconds. EDIT: Enabled V-Sync in Nestopia, no tearing

Not all resolutions centre or fit on the screen the same. You can see in the Street Fighter and Progear screens are cut off on the right. R-Type is cut off at the bottom. USA NES roms are nicely centred but have big black borders, and Euro roms are shifted down significantly (you can see the difference in the two Xevious screens). I don't know if this is typical or what should be done about it. I might be able to improve it by fiddling with the service menu, but it seems impossible to get everything looking right: if one resolution is made to look right, it makes another look wrong again.

I've read on the forum about digital chassis being awkward, and that silver TVs tend to be digital. I wonder if this is the problem. I found this TV on ebay and wondered if it might do a better job:

http://www.ebay.co.uk/itm/110935129563?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[rCadeGaming]

Don't change the TV.  You won't improve any of your problems, you'll just lose the flexibility of the service menu and picture quality probably won't look as good.

The service menu adjustments apply to all resolutions.  You have to set it to a happy medium for everything, then make changes among individual resolutions at the PC end. 

Start with the position controls in MAME (slider controls on the TAB menu in-game).  Don't use the stretch controls, or they'll scale things unevenly, ruining your native resolutions.  Beyond that, I'd be tweaking modelines, but, if you're using GroovyMAME's auto-calculated modelines, Calamity will have to advise you on that.