ao486 Config for a Plain Old CRT TV

_javi_
Posts: 73
Joined: Fri Jun 19, 2020 8:49 pm
Has thanked: 96 times
Been thanked: 20 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by _javi_ »

akeley wrote: Wed Jun 23, 2021 12:45 pm
@_javi_ you can check, perhaps your TV has option called "RGB centering", or something similar, in the "normal" menu. Some newer sets have this, it's a godsend when it comes to horizontal centering. If not, then you'll have to dive into service menu. Perhaps it can be adjusted with modelines, but this is not an operation for the faint-hearted ;)...certainly not for beginners. You touch one value and 5 others will go out of whack...and what might look ok in one core will produce artifacts in another.
Thanks for the tip. Unfortunately, theres no such option in this Sony.

These parameters are what works the best, so far..

[ao486]
;select Full Screen within core OSD menu
direct_video=1
vscale_mode=0
vscale_border=1
video_mode=640,0,58,86,240,1,3,18,12350

(thats the most i can force to the right, using https://www.epanorama.net/faq/vga2rgb/calc.html)

I'll start playing, enjoying it as it is.
Thanks again.
FoxbatStargazer
Top Contributor
Posts: 994
Joined: Thu Dec 10, 2020 5:44 pm
Has thanked: 309 times
Been thanked: 228 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by FoxbatStargazer »

My understanding was that direct_video makes your modeline pointless. Its just going to ask the core for whatever resolution it feels like (which seems to be something like 1440 x 240). I think on this core it also adds some side border to go with the top border on 200p games, to try and have the viewable game area match a 4:3 aspect ratio. You can try to compensate with your TV menu but it will probably throw things way off for other content. Better would be to shut off direct_video and find a useable modeline. You can use the HV integer scale options in conjunction with different resolution widths to adjust the effective border on the left and right, at least within 200p games.
FoxbatStargazer
Top Contributor
Posts: 994
Joined: Thu Dec 10, 2020 5:44 pm
Has thanked: 309 times
Been thanked: 228 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by FoxbatStargazer »

BTW here's some 1440x240 settings I found that work for me, this may work with HDMI->analog converters.

video_mode=1440,40,136,176,240,3,10,6,27000
direct_video=0
vscale_border=20
vscale_mode=0

Video settings in the core:
aspect ratio: full
scale: HV Integer(- or +)

over on scaling filter page: "no interpolation"

DOS text will run edge-to-edge (so may disappear into overscan) but will be pixel-perfect in width and exactly half resolution height. 200p DOS games will have some black border on either side which will get pretty close to 4:3 aspect ratio along with the border on the top/bottom. change scale from HV Integer to Normal if you'd rather have games run to the edge.
flynnsbit
Top Contributor
Posts: 550
Joined: Sun May 24, 2020 8:07 pm
Has thanked: 179 times
Been thanked: 307 times
Contact:

Re: ao486 Config for a Plain Old CRT TV

Unread post by flynnsbit »

thorr wrote: Wed Jun 23, 2021 5:57 am
flynnsbit wrote: Tue Jun 22, 2021 1:44 pm Here is what vmode 4 and vmode 5 "should" do on your set: https://youtu.be/W0ScMbmXMG8?t=32 I tried to capture what it would look like. This is a Samsung GXE consumer set that is RGB modded. It's been a while since I had this setup, I might have been running UniVBE (SDD 5.X) (command is univbe -c2) along with vmode to get the video modes to switch.
Thanks for the info. I just got the 300 game version and ran the update script. I am getting command not found when I try to run vmode. Do I need to get this separately? univbe -c2 works. Thanks!
I can't remember if I included vmode or not, you can get it here: https://www.vogons.org/viewtopic.php?p=133258#p133258
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

FoxbatStargazer wrote: Wed Jun 23, 2021 10:21 pm DOS text will run edge-to-edge (so may disappear into overscan) but will be pixel-perfect in width and exactly half resolution height. 200p DOS games will have some black border on either side which will get pretty close to 4:3 aspect ratio along with the border on the top/bottom. change scale from HV Integer to Normal if you'd rather have games run to the edge.
Tried these settings on my Direct Video...they do work slightly better than thorr's because there is a little bit less left/right border. DOS goes indeed into overscan though (for some reason HV integer doesn't affect it). Hmmm, which one to use then... *scratches head*.

Regarding the other angle, I did install univbe 5.3a, but the command "univbe -c2" doesn't seem to do anything, same for vmode 1-5. Most likely I'm doing something wrong though, or maybe its the fact I'm not running the 300 pack, but some self-made vhd's (with an exception of a "BOOT-DOS98.vhd", which I think comes from it). I'd rather not download this whole huge pack just to try to sort this out though...
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

I haven't tried vmode yet because I need to get the file into the VHD. Is there a way to copy the file to the folders on the MiSTer and from an ssh session, copy the file into the VHD, or from a DOS program within ao486 be able to copy files from the MiSTer folders onto the C: drive? I don't want to mount the VHD over wifi from Windows because any wifi dropouts could cause corruption, and I have dropouts with my MiSTer more than I would like.
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

I just use a little 50MB .vhd to carry files from PC to MiSTer, then mount it alongside bigger ones and copy stuff in DOS.

Been trying to mess with it all a little, but it's all above my paygrade. Found this curious program called VBEHz - seems like you can adjust modelines on the fly in DOS with it?

I'm also looking at AdvanceCAB utilities - from AdvanceMAME DOS days, which I guess is a precursor of crtemudriver. Wouldn't it be wild if you could output via this from ao486?
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

That's a great idea about the 50MB vhd file. I will do it that way. Thanks!
That other stuff looks cool, but I have my doubts whether it would work in the MiSTer since the video implementation is not the same as a real PC. If it works, that would be awesome.
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

flynnsbit wrote: Mon Jun 21, 2021 4:59 am run vmode "insert a number from 0-9" at the dos prompt to change video modes for text and the TDL menu. this will make both legible on a CRT/RGB set. I think I use vmode 4 once you find the one you like, edit autoexec.bat and add it before the tdl command.
I got vmode working, and vmode 6 looks excellent in DOS. However, as soon as I launch a program such as tdl or edit, it reverts back to the original video mode. I ended up putting it in the runme.bat because that is where the tdl command is. I put a pause just before the tdl command to verify that the font looks correct before launching tdl. Are you sure that vmode works with tdl, and if so, do you have any suggestions? I tried univbe -c2 before and after vmode 6 and it didn't make any difference. If I have vmode 6 working and run edit, the font is wrong in edit, but after exiting, the font looks ok again in DOS. TDL does not put the font back to vmode 6 after exiting.
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

I re-setup my screen geometry using the SNES and made some new screen modes for ao486 that are wider and fill the screen. New Best has a slight border and New Best Wider has no border on my screen in DOS. 320x200 games use the center 200 pixels of the 240 to maintain pixel perfection. You can change the vscale_mode to 0 if you want to fill the screen but you will be upscaling and it won't have 1 to 1 pixel mapping.

[ao486]
; Set it to "Variable" in the ao486 core instead of 60Hz
direct_video=0
vga_scaler=1
vsync_adjust=1
vscale_mode=1 ; Set this to 0 if you want to fill the screen but lose 1 to 1 pixel mapping on 320x200 games
;video_mode=1280,170,140,244,240,2,0,22,29020 ; Old Best for ao486 12-8-2020
;video_mode=1280,138,140,216,240,2,0,22,28070 ; New Best 06-25-2021
video_mode=1280,120,140,202,240,2,0,22,27565 ; New Best Wider 06-25-2021


I also applied it to the Menu because the overscan is so large. I noticed that there are borders on the left and right until you let it sit there and it turns down the brightness eventually and then it fills the screen. I may decide to make a new menu mode that is wider to fix that. (Edit: I think my screen just gets wider when the image is less bright. I noticed this in Monkey Island 2 when digging the grave and the lightning struck).

[Menu]
direct_video=0
vga_scaler=1
vsync_adjust=1
vscale_mode=1
video_mode=1280,120,140,202,240,2,0,22,27565

Adjusting the width and positioning of these modelines is quite easy. Here are the steps:
- Start with a working mode like video_mode=1280,170,140,244,240,2,0,22,29020 and plug them into https://www.epanorama.net/faq/vga2rgb/calc.html
- If you want to make it wider, decrease the fourth number (244) - I usually use multiples of 8 (8, 16, 24, etc.)
- Press the calculate button
- Adjust the pixel clock frequency in the tool until the vertical sync frequency is 59.94 and keep hitting calculate to check it
- Usually decreasing the fourth number (244) leaves a gap on the right side, so you need to move it to the right. Press the Right button to see how it adjusts two of the numbers. If you need to adjust it by different amounts than 8 at a time, you can do this manually. Just adjust both numbers by the same amount and make sure the refresh rate stays at 59.94 (It should not change as you move it left or right).

Hope y'all love the new video modes and find this useful.
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

I will try the new modelines soon, they sound promising!

Any chance you could briefly describe the steps to get the vmode stuff working?
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

Sure. I did the following:
- Download the zip file from https://www.vogons.org/download/file.php?id=5159
- Create a 50 MB VHD file in Windows, format it and copy the file to it
- Mount the 50 MB drive in ao486
- Go to the drive (D: or whatever)
- type vmode 6

That's it!
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

Thanks, but that's what I had been doing before and just get garbled screen. It needs univbe as well, right? I'm not using the 300 pack btw. Basically, the way I tried was:
-mount BOOT-DOS98.vhd as C: and some other vhds too
-install univbe to C:, run univbe.exe (the "-c2" doesn't do anything, it seems). From SDD 5.3a I get Tseng SVGA card and VBE 2.0. I've tried 6.7 as well but it sends mixed signals (says VBE 3.0 is enabled, but when I run uvconfig it says there is no supported chipset)
-type vmode 6, screen scrambles, ¯\_(ツ)_/¯
- NO, WAIT! A-HA!

Have just tried it again and the screen scrambles indeed, but only in DosZip Commander I've been using. I was mashing the keyboard trying to go back to the <6 mode and saw that the actual DOS command line looks ok. So when i quit DosZip it's all good. How bizarre.

Then I tried tdl, and it's the same as in your case - goes back to "normal", ie the slightly weird font. I could live with that, but I'd like a DOS navigator to display properly, because I spend a lot of time there. Got to try DN and NC, see if they also get garbled...
flynnsbit
Top Contributor
Posts: 550
Joined: Sun May 24, 2020 8:07 pm
Has thanked: 179 times
Been thanked: 307 times
Contact:

Re: ao486 Config for a Plain Old CRT TV

Unread post by flynnsbit »

Checking if Binary can make TDL not reset for you guys. Have you tried the other lower vmodes? 3,4,5?

In TDL.INI on E:\

Change this line in it to :
set VESA=0h for mode 6
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

flynnsbit wrote: Fri Jun 25, 2021 2:08 pm Checking if Binary can make TDL not reset for you guys. Have you tried the other lower vmodes? 3,4,5?

In TDL.INI on E:\

Change this line in it to :
set VESA=0h for mode 6
Vmode 3 does nothing. 4 and 5 have 40 column text (huge).
setting VESA=0h in E:\TDL.INI does nothing in TDL (is 0 correct? that seems wrong to me). I also tried 06h.
Thanks for your help!
flynnsbit
Top Contributor
Posts: 550
Joined: Sun May 24, 2020 8:07 pm
Has thanked: 179 times
Been thanked: 307 times
Contact:

Re: ao486 Config for a Plain Old CRT TV

Unread post by flynnsbit »

thorr wrote: Fri Jun 25, 2021 4:07 pm
flynnsbit wrote: Fri Jun 25, 2021 2:08 pm Checking if Binary can make TDL not reset for you guys. Have you tried the other lower vmodes? 3,4,5?

In TDL.INI on E:\

Change this line in it to :
set VESA=0h for mode 6
Vmode 3 does nothing. 4 and 5 have 40 column text (huge).
setting VESA=0h in E:\TDL.INI does nothing in TDL (is 0 correct? that seems wrong to me). I also tried 06h.
Thanks for your help!
The huge text is the point on a 15hz 200 line crt. I don't think 6 is the one you want but it is hard to test where I am at so if you can't find a vmode that you like, that also sticks inside of TDL then I can't help any further.
try them all 0 through 9
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

flynnsbit wrote: Fri Jun 25, 2021 6:18 pm The huge text is the point on a 15hz 200 line crt. I don't think 6 is the one you want but it is hard to test where I am at so if you can't find a vmode that you like, that also sticks inside of TDL then I can't help any further.
try them all 0 through 9
Thanks. Mode 6 on my CRT is 80 columns but completely pixel perfect and legible. Mode 3 seems to be the standard mode and is not pixel perfect and missing horizontal lines.

I am confused about VESA=0h. Did you mean 6h? Is there a table that translates the vmodes to the equivalent VESA hex code used in TDL.ini? Is TDL.ini using vmode or something else (can I just say VESA=6)? When you say try them all, do you mean VESA=0h, VESA=1h, etc?
ash2fpga
Posts: 237
Joined: Tue May 26, 2020 6:20 pm
Has thanked: 62 times
Been thanked: 28 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by ash2fpga »

Here are video modes from Ralf Brown's Interrupt List:
http://www.ctyme.com/intr/rb-0069.htm

May or may not be applicable to TDL, though.
_javi_
Posts: 73
Joined: Fri Jun 19, 2020 8:49 pm
Has thanked: 96 times
Been thanked: 20 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by _javi_ »

thorr wrote: Fri Jun 25, 2021 9:37 am
...

[ao486]
; Set it to "Variable" in the ao486 core instead of 60Hz
direct_video=0
vga_scaler=1
vsync_adjust=1
vscale_mode=1 ; Set this to 0 if you want to fill the screen but lose 1 to 1 pixel mapping on 320x200 games
;video_mode=1280,170,140,244,240,2,0,22,29020 ; Old Best for ao486 12-8-2020
;video_mode=1280,138,140,216,240,2,0,22,28070 ; New Best 06-25-2021
video_mode=1280,120,140,202,240,2,0,22,27565 ; New Best Wider 06-25-2021

....

Hope y'all love the new video modes and find this useful.
No matter what modeline i use, i get a rolling screen unless i set direct_video=1.

Maybe the parameters for the ioboard vga output are not the same when using hdmi to vga/rgb adapters. :?:

btw, the more i use exodus/dosbox on my pc (super duper QHD gaming monitor), the more i want ao486 on the sony TV.
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

thorr wrote: Thu Jun 24, 2021 10:48 pm That's a great idea about the 50MB vhd file.
Actually, I've just realized MiSTer has shared folder ability. D'oh. If you use flynnsbit's pack it's all already setup: just make a "shared" folder inside fat/games/ao486/ and you can transfer files from PC via ssh. The shared folder is drive Z: in DOS.
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

_javi_ wrote: Fri Jun 25, 2021 9:02 pm
No matter what modeline i use, i get a rolling screen unless i set direct_video=1.

Maybe the parameters for the ioboard vga output are not the same when using hdmi to vga/rgb adapters. :?:

btw, the more i use exodus/dosbox on my pc (super duper QHD gaming monitor), the more i want ao486 on the sony TV.
I definitely feel sorry for your situation. The timing parameters are the same, but there are other settings in the ini that might need to be changed. Try adjusting these one at a time to see if it helps:
ypbpr=0 ; set to 1 for YPbPr on VGA output. (I assume you have this set to 1)
composite_sync=0 ; set to 1 for composite sync on HSync signal of VGA output.
fb_terminal=1 ; 1 - enabled (default), 0 - disabled (I am not sure if this makes any difference or not, but I included it anyway)

I am 99% certain you need a different solution than the HDMI to VGA cable you are using. Did you do the sync on green mod to it? The HDMI converter that I am using is no longer made. I ordered a different one from aliexpress.com to test (I don't know how well it works), but the shipment got cancelled for whatever reason so I didn't get a chance to test it. I also found it on alibaba.com but haven't ordered it yet: https://www.alibaba.com/product-detail/ ... 14489.html If you got a VGA IO board, it should work but the color is not quite as good as using the HDMI output. You may or may not be able to tell the difference and be just fine with that solution.

Edit: I just placed an order for the one from alibaba.com. In order to buy just one, you need to click "Buy Samples". It will be several weeks before I get it, but I will report back whether it works or not. Also, you may already have a VGA IO board. I am not sure from your posts. If you do, you can try the timings on that and if they work it will confirm the issue lies with your HDMI to VGA solution. If you didn't do the Sync on Green mod, that would explain why it doesn't work.
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

akeley wrote: Fri Jun 25, 2021 9:25 pm
thorr wrote: Thu Jun 24, 2021 10:48 pm That's a great idea about the 50MB vhd file.
Actually, I've just realized MiSTer has shared folder ability. D'oh. If you use flynnsbit's pack it's all already setup: just make a "shared" folder inside fat/games/ao486/ and you can transfer files from PC via ssh. The shared folder is drive Z: in DOS.
That's awesome! Thanks for the information.
bbond007
Top Contributor
Posts: 519
Joined: Tue May 26, 2020 5:06 am
Has thanked: 85 times
Been thanked: 198 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by bbond007 »

thorr wrote: Fri Jun 25, 2021 6:58 pm Thanks. Mode 6 on my CRT is 80 columns but completely pixel perfect and legible. Mode 3 seems to be the standard mode and is not pixel perfect and missing horizontal lines.
I believe 0 tells it to not set the video mode.

Anyway,

Mode 6 is a graphics mode - the screen is stored in a bitmap. The BIOS is essentially emulating a character display in graphics.

TDL is designed to run in text mode where the screen is stored as an array of character and attribute data. Text mode works similar to tile maps for game consoles where the character ROM is like the tiles and the video RAM is like the map.

TDL does not use the BIOS for screen writes and manipulates the RAM directly, so this simply won't work...
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

Thank you very much for the detailed response. That makes sense. I can still use TDL just fine so it is not the end of the world if it is not pixel perfect. At least DOS can be now which is a nice improvement anyway.
bbond007
Top Contributor
Posts: 519
Joined: Tue May 26, 2020 5:06 am
Has thanked: 85 times
Been thanked: 198 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by bbond007 »

thorr wrote: Sat Jun 26, 2021 12:09 am Thank you very much for the detailed response. That makes sense. I can still use TDL just fine so it is not the end of the world if it is not pixel perfect. At least DOS can be now which is a nice improvement anyway.
I tried to make it work with pcem then I realized why it was not working.

Ideally I think you need a GFX mode launcher....
FoxbatStargazer
Top Contributor
Posts: 994
Joined: Thu Dec 10, 2020 5:44 pm
Has thanked: 309 times
Been thanked: 228 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by FoxbatStargazer »

_javi_ wrote: Fri Jun 25, 2021 9:02 pm
No matter what modeline i use, i get a rolling screen unless i set direct_video=1.

Maybe the parameters for the ioboard vga output are not the same when using hdmi to vga/rgb adapters. :?:
To reiterate, your modeline is irrelevant when using direct video, its just using whatever resolution the core decides on. So yes the direct video resolution settings are different, but you can't control them!

Direct_video seem to pass through some modifications of the analog signal that will not appear from HDMI otherwise. Ypbpr and csync in the ini normally only affect the analog out, that might be passed along HDMI when you use direct video. I'm not so sure about the SoG switch.

I don't know how your "VGA adapter" is connecting to your TV. I'm assuming its HDMI->VGA, and then VGA->?. You might need to find a more fully featured adapter if you ever want to move beyond direct video, or else get a working I/O board (which can use ypbpr/csync in conjunction with vga_scaler)

I will say direct video seems to display 200p DOS games pixel-perfect, just maybe not centered where you will like. 720x400 DOS OTOH will always be slightly ugly (though still readable), though maybe by changing the vmode within DOS you can get around that.
thorr
Top Contributor
Posts: 1099
Joined: Mon Jul 06, 2020 9:37 pm
Has thanked: 535 times
Been thanked: 252 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by thorr »

I got a new Sony 20-KVFV300 CRT and spent quite a bit of time on it. I set up the TV service menu geometry to work well with SNES and NES. I tried to find a happy medium vertically for 224p and 239p resolutions. 239p is cropped by about 6-7 lines on the top and bottom, but 224p fills most of the screen with tiny black bars on top and bottom. I wanted to make 224p my primary geometry because most consoles use that. My TV has a couple of horizontal white lines in the upper left corner that I try to move above the screen so they are not displayed, and keep as much of the normal lines visible as possible. If anyone tries my numbers and finds the geometry is slightly off compared to their settings, this may be the reason.

For ao486, here is my video mode for maximizing the vertical screen size for 320x200 games and DOS. There are still black bars on the top and bottom, but they are as small as I can get them and still have it be in sync on the monitor. The left and right side go right to the edge without cutting anything off.
[ao486]
; Set it to "Variable" in the ao486 core instead of 60Hz
direct_video=0
vga_scaler=1
vsync_adjust=1
vscale_mode=3
video_mode=1280,95,140,187,240,11,0,19,27543 ; best for 320x200 and DOS

The above will cut off the top and bottom on 320x240 games like Epic Pinball. I still need to work on settings for this mode.

In the meantime, for the menu, currently I have these settings, but I may tweak them further:
vscale_border=5 ; vscale_border=5 does not work with ao486
video_mode=1280,112,140,178,240,0,0,18,26445
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

@thorr: did try your latest...work ok, though the difference is not that big compared to other ones. I guess this is pretty much as good as it gets - which is great already. Actually, DOS itself is now squashed and looks kinda 320x200, but that's ok.

I was doing some random comparisons vs games on my PC+VGA CRT and was thinking about AR. Obviously the VGA monitor has 4:3 AR while this method yields a squashed image...a bit like Amiga. I don't suppose there is any chance to produce a 4:3 modeline (or force 320x240?), even if it had some more black bars on the left/right?

I'm just curious really... now, in theory 4:3 should be a standard, but I think in practice not all the games were produced with it in mind (unlike for consoles). Some (most?) DOS games look ok in 4:3, but some do look too stretched (Advanced Destroyer Simulator is a good example, because it has a lot of round dials).

Also, an unrelated thing: I fired up Conan the Cimmerian(1991) and saw that some colours are different - if anybody wants to check, just Restore Game and look at the buildings. In Dosbox on my Windows IPS panel they are white-ish, like marble. Here, both on a CRT TV & VGA (real DOS PC) they look similar to the streets - shade of brown. Why the difference? I know the LCD tech, and Win colour profiles might differ from CRTs, but have never seen such pronounced discrepancy. It's also odd, because you'd've thought the marble one was the intended colour...
FoxbatStargazer
Top Contributor
Posts: 994
Joined: Thu Dec 10, 2020 5:44 pm
Has thanked: 309 times
Been thanked: 228 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by FoxbatStargazer »

The games are 320x200 and you are displaying them on what is likely 240p(244p) display at 60hz. So either you eat some ugly scaling, or you're going to have some black bars on top and bottom. (Or maybe you can really push your vsize TV adjustment?)

The horizontal resolution of CRTs is more arbitrary so we have some choices here. Given you accept black bars on top/bottom to get the vertical resolution right, you have to either stretch games edge to edge (giving that squashed/PAL look), OR you can put black bars on the sides too, to try and get a 4:3ish image in the center. The settings I posted used 720 wide or 1440 wide to get the full 720 DOS text resolution, if you turn on HV Integer scale, then the games will only go to 640 or 1280 wide, leaving black on either side, which will end up not exactly but very close to 4:3. So if you want to try 4:3 look I would recommend those.

To be clear on a real PC monitor you would always see 4:3 and yes, the pixels would be tall. Devs varied on how much they corrected their games with what is essentially 16:10 if you treat as square pixels. Everything in Doom is kind of fat and intended to be squashed together for example. But a more interesting example is duke nukem 2, where the proportions on the large-style intro scene art are very fat and meant to be compressed to 4:3, however the game itself seems to use perfect squares in level design that get squished to tall rectangles on a 4:3 display. 4:3 is how we played it at the time (unless you really wanted to use vertical adjustments to put black bars on top/bottom), but of course its your choice how you want to play the games now.
akeley
Top Contributor
Posts: 1303
Joined: Mon May 25, 2020 7:54 pm
Has thanked: 416 times
Been thanked: 399 times

Re: ao486 Config for a Plain Old CRT TV

Unread post by akeley »

FoxbatStargazer wrote: Wed Jul 07, 2021 6:58 pm The games are 320x200 and you are displaying them on what is likely 240p(244p) display at 60hz. So either you eat some ugly scaling, or you're going to have some black bars on top and bottom. (Or maybe you can really push your vsize TV adjustment?)
I've been dealing with this TV maths thing for years, but it somehow still remains black magic for me. My simpleton of a brain just struggles to visualize it. After all, the arcade/console resolutions are also in the 190-240 range, and yet it's possible to fill the screen with them. I know you're obvioulsy correct, it's just...ah, nevermind :) I guess I'll never "get" it.

Sure, I could stretch it in the service menu, but then it'd mess up everything else, so...
FoxbatStargazer wrote: Wed Jul 07, 2021 6:58 pm The settings I posted used 720 wide or 1440 wide to get the full 720 DOS text resolution, if you turn on HV Integer scale, then the games will only go to 640 or 1280 wide, leaving black on either side, which will end up not exactly but very close to 4:3. So if you want to try 4:3 look I would recommend those.
I did try these from 2 pages ago, with the "video_mode=1440,40,136,176,240,3,10,6,27000" modeline. When I measured the result with a tape, the ratio was ~1.5 which is indeed better than 1.6 of 320x200. Still, would it be possible to push it even more towards 1.33 (4:3)? The black bars are ok, since on 21" TV the image is still bigger than even on a large PC monitor.
FoxbatStargazer wrote: Wed Jul 07, 2021 6:58 pm To be clear on a real PC monitor you would always see 4:3 and yes, the pixels would be tall. Devs varied on how much they corrected their games with what is essentially 16:10 if you treat as square pixels.
Yes, it's rather interesting, and overall all the different AR results don't really bother me (the only thing I can't bear is bad scaling). People like me, who also grew up with machines like PAL Amiga got used to all kinds of TV weirdness. Back then we didn't have much choice but now it's nice to be able to experiment with different methods and settings.
Post Reply