Epia 800 VESA Modes for MAME..... \ VOGONS

Epia 800 VESA Modes for MAME.....

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First post, by GonzoVGNS-1

Posted on 2018-12-31, 03:02

GonzoVGNS-1 Offline

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Joined: 2018-12-31, 02:50

New member here.

I built a countertop MAME machine based on an ePIA 800, a 10" datalux SVGA LCD screen, and stuffed it all into one of those iCade enclosures they sold a while back for iPad users (I got that for a quarter at a garage sale).

Its running a few versions of DOS MAME with ArcadeOS as the frontend, and about 150 of my favorite golden age games.

The Epia board is one of the few ITX sized devices where the AC97 has support for sound blaster emulation (though its not always great, and you have to figure out that VIA forgot one of the two required DOS tsrs in their drivers package).

Anyway, here's my frustration: This LCD screen was repurposed from a previous MAME build using an older system but with a PCI video card that was supported by Scitec Display DR, and therefore had great VESA mode support.

I'm running all the games rotated right with the screen oriented in vertical position. This same LCD with the same basic software played / displayed several of my favorite games correctly, whereas on the Epia the modes necessary to correctly letterbox horizontal games on the vertical screen (400x300, in particular and a few others) simply are not available and these games cannot be displayed right. About the only thing that works is forcing 640x480 and thumbnailing the image in the middle of the screen, wasting bout 60 percent of the available display area.

My research says the Epia 800 northbridge is running a Trident Blade3d chip. Does anyone know the secret to access all the 8 bit low-res VESA modes on this thing? Is that even possible? Its only about 8 games that I've got to disable at this point, but its some of the great ones so I'd love a solution.

I tried the utilities in the VESA thread here on VOGONS. None of them seem to accomplish what I need. I can get one of them (VBE Plus) to emulate the necessary modes, but it merely does this by creating a subscreen sized area with the remainder blanked. None of the display refresh tweakers work because (they say) the Epia board is not acting like VESA 3.

Part of me wonders if this board locks out all the low BPP and low res VESA modes because it does have a TV out jack.

Any thoughts?

Reply 1 of 2, by matze79

Posted on 2018-12-31, 19:58

matze79 Offline

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Maybe you can use a PCI Card with VBE 3.0 Support ? there also Risercards avaible if you need to change card position to fit it in your case.

The Trident Blade 3D only supports VBE 2.0.

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Reply 2 of 2, by GonzoVGNS-1

Posted on 2019-01-01, 04:52

GonzoVGNS-1 Offline

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Posts: 2
Joined: 2018-12-31, 02:50

matze79 wrote:
Maybe you can use a PCI Card with VBE 3.0 Support ? there also Risercards avaible if you need to change card position to fit it in your case.

The Trident Blade 3D only supports VBE 2.0.

Well, if it _fully_ supported VBE20 it would be fine. But the problem is it supports VBE 2.0 only at 640x480x16 & 800x600. What I really need are things like 352x240 and 400x300 at 8bpp...

I wish I could use a riser, but the Epia board is tiny, and the enclosure I put it into has maybe 1.5 inches of clearance above the board. So even a 90 degree riser would not work, alas. To do that, I'd have to put a bulging hump out of the back of the box like an old television -- and if I'm going to have to go in that direction, I'd rather replace the Epia board with one of the later models with better graphics, and use the riser (really 90% or PCI ribbon) to put a nice PCI sound-blaster live, as sound could really be better on this machine.

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