SCART CRT TV And GroovyMAME Thread 2

[Calamity]

I was also wondering why I get  borders on top and bottom in capcom games? They seem to fill out the screen for others without any monitor specs. Horizontal porch is good though.

Capcom games are 224 lines tall, you need to use your TV's service menu to stretch the vertical amplitude in order to fill the screen for those games.

[Endprodukt]

Okay, thanks! I just hope I can get a sharper picture... Any advice on that?

[Calamity]

Okay, thanks! I just hope I can get a sharper picture... Any advice on that?

Is that an overall problem (CRT) or just some games are affected (software)?

[Endprodukt]

seems to be overall. I allready tried to get the focus better but it seems like as there is some filtering going on. I'm comparing to my second tv which was a dirt cheap 25" crt that seems to look better (but can't produce sound when switchres is on... remember ?).

[Endprodukt]

Ok I went back to my old tv (thomson crt with a beko chassis) and I'm having a great picture but some trouble with vertical (and some horizontal) games. It seems like the tv actually fits the screen vertically. Works on some games but not on all. I have the problem that the bottom of the screen is distorted, looks like that:



It's a little hard to setup the tv's geometry because I have different settings for 50 and 60hz. This is an advantage for some stuff though. Maybe someone has an idea how I can get rid of the distortion?

[Calamity]

Hi Endprodukt,

That problem might have no solution, it seems to be related to the digital chassis that TV has. Try to play with the vertical porch values in Arcade_OSD for one of the 256 lines to see if you can achieve something interesting, anyway. Do 224/240-line resolutions have this problem too?

[kourampies]

I can get for free 3 big CRT tvs, 32" or even more. They are 16:9, dont know if they are 100hz, and they are from a Carrefour In store brand called Bluesky, from the early 00s. They are definetely a digital chassis, but I have no idea whats the OEM, and how they handle 4:3. Im 99% sure there is some way to force 4:3 on them, and I dont have any problem with the black borders on the sides. Do you think I can do anything interesting with them?

I will definetely get 1 for experimenting, but I can only do one trip to get them, so I either get them all the first time, or I get one. My back is killing me and I dont have much free space in here, do you think its worth getting all 3?

[Paradroid]

Back when I first got into SCART TVs I hauled a 16:9 Toshiba in from the street. It was the first TV that I managed to get VGA to SCART working on. I've tried other widescreens such as the Loewe Xelos and Sony KV-HR32M31. The Sony was okay in RGBHV mode but the Loewe was awful! These chassis types tend to have a lot of processing going on and are a world away from earlier analog and digital chassis 4:3 TVs.

Personally, I don't think they're much use for retro gaming. Maybe they're good for running PC games on a CRT or using your computer as a HTPC but I wouldn't bother running GroovyMAME on one of these beasts.

If you're up for experimenting, grab one! Personally, I wouldn't bother with all 3 though...

[kourampies]

I just got a Hitachi CP2856 4:3. Its almost unused, and it looks beautiful. It also has a service menu that supports all kinds of adjustments, really easily. But it doesnt turn on. Some kind of power protection kicks in and turns it back off before it starts running

What a shame, and I was so happy when I was carrying this beast home that I almost forgot how badly my back hurt 

[Paradroid]

I know how you feel... Sucks when you find a great unit and it dies (or you kill it ). I'm still kicking myself for accidentally smoking this one.

[kourampies]

I know how you feel... Sucks when you find a great unit and it dies (or you kill it ). I'm still kicking myself for accidentally smoking this one.

Perhaps I ll try to repair it myself, since repairing it in a store will be expensive, and I cant say I really trust them, and also a big fuss due to its size. The service manual is excellent and very easy even for someone with absolutely no experience, and I can borrow an oscilloscope from a friend. But I suck at any kind of craft/soldering/mending, and the CRT high voltage and discharge scares the ---steaming pile of meadow muffin--- out of me. But still,  I think I ll might try it. I just want to mess with it it, It looks amazing even when shut down.

[Endprodukt]

I just scored a NOS 25" Arcade Monitor from a Company called "Monitor" that actually built 1:1 Hantarex Polo. I've setup everything that came up in this thread and it's working awesome for the most part. I just have some trouble with some games like Neo Geo stuff. Most games are centered horizontaly and line up perfectly... like MK, SF and many others. Neo Geo is just off. Usually it's too small and I have a pretty big border on the left and some on the right. What can I do about it?

[Endprodukt]

So I checked many games and they're all over the place horizontaly. Some fit perfectly, some are just too small. Is that normal?

[Endprodukt]

Okay I realize it's depending on the game i I have borders horizontaly. What would be the best mode to check the center horizontaly on my arcade monitor before setting up the geometry in arcade osd?

[Calamity]

Okay I realize it's depending on the game i I have borders horizontaly. What would be the best mode to check the center horizontaly on my arcade monitor before setting up the geometry in arcade osd?

Usually you get more accurate average values when you use a high-horizontal resolution mode. This is so because we can only adjust horizontal values by using blocks of 8 pixels (characters), so the highest the resolution the finest the granularity and the values reported will be more representative as reference ones. Once you get that reference modeline perfectly centered with Arcade_OSD, write down the values and use them as input for a custom monitor_specs line. That will produce modelines with borders close to the reference ones. Don't expect perfection. However if you keep getting modes that are badly cropped or have uneven borders bigger than 2cm then something is going wrong. Not all monitors behave the same. Some are sensitive to hfreq differences, in terms of horizontal shifting. For these cases you need to set up a narrow hfreq range, like 15700-15800, instead of opening it more.

Also, bear in mind that some machines like Neo Geo do have black borders built in on both sides of the frame, this is how the actual game was, so there's nothing we can do about it.

[Endprodukt]

Thanks,

I tested it with a resolution of 1280x240 60p. I got very big borders!

The monitor is the same as an Hantarex Polo 15khz and is built in the same factory from the successor "Monitor Electronics".

[Calamity]

Thanks,

I tested it with a resolution of 1280x240 60p. I got very big borders!

The monitor is the same as an Hantarex Polo 15khz and is built in the same factory from the successor "Monitor Electronics".

Hi Endprodukt,

I'm not sure I expressed the idea clearly. You're likely going to get wrong borders whatever resolution you test, what you need to do is to manually tweak one resolution in order to get the right borders, by means of the controls inside the horizontal geometry submenu. For doing this it's better (not necessary) to use a high horizontal resolution. Then use the values obtained to create a monitor_specs line.

[Endprodukt]

I got that, that's not the problem and I did that. I used the 1280x240 mode and centered the picture using the horizontal geometry submenu in arcadeOSD. However, I wanted to center the picture with the monitor itself first BEFORE I started tweaking the software. Know what I mean? What I did was that I adjusted the monitor at my desktopresolution (640x480) to fit perfectly horizontaly. I worked from there. Is that the correct way?

[Calamity]

Ah ok, sorry I think I get it now. Yes that's a correct way.  So once you have your monitor fit at 640x480, you launch 1280x240 with Arcade_OSD, center the mode and still get big borders, is that it? That's because you also need to reduce the values of both HfrontPorch and HBackPorch, these correspond to left border and right border respectively. Hope that's what you mean.

[Endprodukt]

Yes that's what I did but translating the values I got from arcade osd gave me borders and I had to tweak it step by step manually. It's okay now and I don't think this can be any more perfect than it is now! Thanks for all your support!

[Calamity]

Alright. There's still some room for improvement by means of the simple trick of doubling the horizontal resolution for the lowest res modes. This is absolutely transparent and the picture quality is zero affected. You do this by setting a value for the dotclockmin option of around 8.0 MHz, both in vmmaker for creating the modes and in mame.ini. Doubled resolution often result in more accurate borders for the reasons explained above. However if you're using other emulators where the original resolutions are still required this is not probably an option.

[Endprodukt]

I'm using several emulators so that's no option. I think I'm allready pretty close to have a very good size of the picture in most games!