darry wrote on 2021-02-22, 17:09:

Thank you, but unless I am misunderstanding, VGATV is meant to use a VGA card's output to drive a monitor that is 15KHz capable […]
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maxtherabbit wrote on 2021-02-22, 16:53:

darry wrote on 2021-02-22, 16:50:

I think you misunderstand me . Sorry if I was unclear . I did not mean to imply using an EGA monitor on a VGA card. I was suggesting to use a TSR to force a VGA card into 60Hz when running EGA or CGA software while displaying on a VGA monitor .

VGATV does this

Thank you, but unless I am misunderstanding, VGATV is meant to use a VGA card's output to drive a monitor that is 15KHz capable . I don't see how it would work to drive a standard VGA/SVGA monitor, unless one also uses a scan doubler like an OSSC .

I was wondering about a way to get EGA and possibly CGA backward compatible modes on a VGA card to actually output directly at 60Hz to a VGA or SVGA monitor while maintaining the VGA card's native line-doubling (when required for 320x200 or 640x200) .

EDIT : As a bonus, if 50Hz could be maintained in Hercules mode, that would be great, though I do not think I even still own a VGA card with Hercules graphics compatibility .

oh right you did say VGA monitor, I just saw 60Hz

And what exactly speaks against 60Hz in a 400 line mode (or scan-doubled 200 line mode) on a VGA card?
Wouldn't that be what you get when you use the 480 line mode's sync settings?

I got into PC gaming in the 90s. I ran into a few old EGA games but I always ran them on a VGA system to begin with.
Going back to the 80s I prefer non-x86 platforms.
But this is the first time I've seen discussion of a mismatch with the refresh rate so that is interesting.

I have too much clutter so I couldn't justify keeping an EGA monitor around. If I somehow found one I'd try to find something to play on it, but I'd probably end up wanting to liquidate it for cash.
I do keep some CRT TVs though. I find them more generally useful for my interests.
If I had a CGA card I'd be interested in hooking it up to a TV through Composite or S-Video. I know that's simple with Ataris and Commodores, but I don't know anything about CGA.

As for EGA 60Hz... what would happen if I played such games using a VGA card, attached to a comparatively modern IPS monitor that internally interpolates 70Hz back to 60Hz? Would that just make it worse?

Benedikt wrote on 2021-02-22, 18:41:

And what exactly speaks against 60Hz in a 400 line mode (or scan-doubled 200 line mode) on a VGA card?
Wouldn't that be what you get when you use the 480 line mode's sync settings?

I once had a TSR that enabled to do things like just this. I used it to play 200/350/400 line games where the 286-12 couldn't keep up with 70Hz refresh at a lower refresh rate mostly. Of course, you could also use it for cheating in games that were designed for 70Hz and would run slower than expected with a lower refresh. If I remember correctly, the no-name VGA monitor (no SVGA support) synced at 59-71Hz in all of its modes, so you could run 350 and 400 line modes at 480 line timing and still get the correct line spacing if the sync polarity still indicates 350 or 400. Of course, running the 400 line mode at 60Hz (by increased blanking) is out-of-spec and your results may vary.

I might try to dig out the old tools (I did it as a combo tool made from a user interface tool that allowed you to adjust the vertical timing and a second TSR tool that copied the VGA parameter table from ROM to RAM, so the user interface tool is able to patch it) the next days if there is interest.

mkarcher wrote on 2021-02-23, 22:33:

Of course, you could also use it for cheating in games that were designed for 70Hz and would run slower than expected with a lower refresh.

not only do some games run slow, I've seen some that pitch down the audio too

it's not enjoyable

I have an EGA monitor thanks, works well and it was free.

Caluser2000 wrote on 2021-02-24, 04:42:

I have an EGA monitor thanks, works well and it was free.

Did you consider it before getting it? How much do you use it compared to your other displays? Would you have gotten it if it wasn't free?

I have an EGA monitor (IBM 5154) that I've tried to have repaired twice, each time I ran it at 15khz it died within 2 minutes, even though the guy swears he ran it for hours at the shop. My guess is he didnt test 15khz. I figure I'll just save it to repair myself at this point, but I don't really have room to keep it out so I haven't tried yet. It doesn't help that I've stored away the IBM AT it was supposed to be paired with in favor of an Amiga 2500 for now.

jarreboum wrote on 2021-02-24, 06:35:

Caluser2000 wrote on 2021-02-24, 04:42:

I have an EGA monitor thanks, works well and it was free.

Did you consider it before getting it? How much do you use it compared to your other displays? Would you have got it if it wasn't free?

I considered nothing. A by chance acquisition really. It came with and xt-turbo system with ega video card and xt enhanced keyboard. The system had a dead mfm drive.

The guy I got it from ran a ma and pop computer shop. He was interested in Amiga systems and didn't want the ega monitor or xt-turbo system. Got some other stuff as well. A TVM monitor with a ega, amber and green option .

darry wrote on 2021-02-22, 07:26:

I don't believe I recall ever seeing an actual EGA monitor in action, at least not in person .
Does EGA really look different on an actual EGA monitor versus on backwards compatible VGA card ? Are there any compatibility issues ?

I always assumed that having EGA content on a VGA setup was pretty equivalent to having it on an actual EGA setup . Please correct me if Iam wrong .

I used to occasionally visit a schoolmate's house in the late '80s and his dad had an XT clone with an EGA monitor. What stood out to me was that the 320x200 graphics mode used in most games would be displayed with scanlines. I've only ever seen this on an actual EGA monitor. I never saw scanlines at 320x200 on CGA or VGA monitors.

I also saw a version of Mahjong running in 640x350 color mode on that same EGA monitor. It looked incredibly lush and crisp to me and obviously, there werd no scanlines at that resolution.

This gave me the impression that EGA monitors were designed primarily for the higher resolution graphics and text modes, and that they kind of had to be coerced into displaying those lower CGA-compatible resolutions.

digger wrote on 2021-02-24, 11:39:

I never saw scanlines at 320x200 on CGA or VGA monitors.

That's weird, they're very visible on CGA unless the monitor is extremely fuzzy/out of focus.

VileR wrote on 2021-02-24, 14:00:

digger wrote on 2021-02-24, 11:39:

I never saw scanlines at 320x200 on CGA or VGA monitors.

That's weird, they're very visible on CGA unless the monitor is extremely fuzzy/out of focus.

Hmmm... Now that I think of it, other than my Dad's Olivetti M24 with its proprietary 640x400 graphics card with CGA compatibility (without any scanlines) I haven't seen a lot of actual CGA monitors in action.

So not only does CGA have snowy artifacts and limited color graphics modes, it also shows scanlines? It truly was a shitty graphics standard.

I have a Mitsubishi XC1410C EGA monitor that was given to me quite a while ago. I haven't actually had a chance to try it out though.

digger wrote on 2021-02-25, 00:08:

So not only does CGA have snowy artifacts and limited color graphics modes, it also shows scanlines? It truly was a shitty graphics standard.

It essentially has to show scanlines, because it would not otherwise have the vertical resolution for an interlaced picture with 480 lines.
CGA screens use TV picture tubes, after all. De-focusing them so much that no scanlines are visible would also render 80 column text unreadable.

I have a multisync monitor that is capable of MDA/CGA/EGA/VGA... in monochrome. Enough for me.
Would I buy a color EGA monitor if it was available and moderately priced? Yes sir, I would.
Too bad CGA and EGA was never a thing here, "we" skipped from monochrome straight to VGA, that's the reason I have plenty of hercules monitors and no CGA or EGA. It remains a dream.

digger wrote on 2021-02-25, 00:08:

Hmmm... Now that I think of it, other than my Dad's Olivetti M24 with its proprietary 640x400 graphics card with CGA compatibility (without any scanlines) I haven't seen a lot of actual CGA monitors in action.

Ah, yeah, then you would've seen a double scanned version of CGA on that.
The first monitor on our home PC was monochrome CGA+MDA (the clone card we had in there could also show MDA-resolution text on it). I was actually jealous of the kid upstairs who had a color one.

So not only does CGA have snowy artifacts and limited color graphics modes, it also shows scanlines? It truly was a shitty graphics standard.

Yes, but you have to remember it was '81. All home computers back then were using either TVs or TV-resolution monitors. Even the best ones in the color/graphics department (probably the Atari 800 back then) were all scanlines all the time. 😉

Most of them had the bus-contention issue too (the cause of 'snow' on CGA), but thankfully they typically saw fit to include a hardware interrupt which made it easy to get around... unlike CGA, where you have to poll or blank the screen.

digger wrote on 2021-02-25, 00:08:

So not only does CGA have snowy artifacts and limited color graphics modes, it also shows scanlines? It truly was a shitty graphics standard.

Yes, yes, it kinda was! 😁
To be fair, though, the original CRTC chip, the Hitachi HD46505, wasn't really designed with graphics in mind.
It was more of a highly programmable text generator, I think. 😀

Also, both CGA and MDA were really messed up from the start by IBM, anyway.
MDA boards had colour support originally (RGB) which was removed later on and CGA had a flawed circuitry (incomplete addressing, a potentially usable, but broken 640x200 4c mode)..

In an alternate reality, there must be a CGA based on, say, the MB89321A or µPD7220 / U82720.. 😀

https://en.wikipedia.org/wiki/NEC_%C2%B5PD7220

http://www.st.rim.or.jp/~nkomatsu/crtif/HD46505.html
English Translation

Edit: Technically, scan lines are always *there* but not always visible.
Also no offense, CGA's quirkiness is perhaps part of the fun. 😉

Here is my setup.

Used to be Pentium 3@1100 on the left, 386DX33 with EGA on the right. Keyboard and mouse are shared using a KVM and an ISA8 PS/2 adapter for the 386. Got the screen relatively cheap with a complete 286 computer (it was a full AT desktop, so I had to get rid of it because I didn't have the space).

Honestly, I don't use the EGA screen too much. It has an annoying high-pitched sound when it works (I guess this is what's called "coil whine") and I'll never dare to attempt a repair on a CRT screen. However, it did find a new use for me when I got my hands on a Tandy 1000SX. That machine uses an MFM drive (and I love its sound), so the screen noise is less noticeable.

Would I search for an EGA screen specifically? Probably no. However, old curved CRT screens really look a lot better for 2D graphics in DOS. So if I had the choice between my current setup and a single NOS non-flat SVGA screen, I would probably pick the latter. I love the colors on the Trinitron tube of my CTX, but the flat screen and tiny dot pitch are not that great for pre-Win9x games.

Is there a comprehensive list of EGA monitors anywhere? I just know about the 5154.

just EGA or also multisync monitors that speak TTL?

there's at least this one ^^
https://www.youtube.com/watch?v=9cn8eQoMXdk