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MDA/CGA/EGA to VGA Converter Released!

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Reply 320 of 341, by retrocanada76

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Yep, but that would only work for these VGA-like modes. Can it boot from these modes ? Otherwise you'd get a blank post.

Unless it is a multisync monitor that accepts both 15hz and 31Khz.

Reply 321 of 341, by ibmapc

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retrocanada76 wrote:

Yep, but that would only work for these VGA-like modes. Can it boot from these modes ? Otherwise you'd get a blank post.

Unless it is a multisync monitor that accepts both 15hz and 31Khz.

Yeah, that was on my mind also. Would need to put a command in autoexec.bat to switch to 640x480. I don't think EGA Wonder can be set to boot in the higher resolutions. Would be great to come up with way to switch between the MCE2VGA and this simplified "Adapter" or "Resistor Array". Maybe something like this https://www.amazon.com/Duttek-2-Port-Monitor- … A3KE08BRD5YYQBR with a Y cable supplying signal to both the MCE2VGA and the "Resistor Array". My question is, would the monitor tolerate the "Out Of Spec Frequency" when the switch is not set to the correct position. I think a modern LCD panel would probably just go blank or display an error message. But, a CRT display may be damaged by the "Out Of Spec Frequency".

Reply 322 of 341, by suntac

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retrocanada76 wrote:

640x480 and 800x600 are on the VGA spectrum. The device does not have memory enough for holding an entire frame. Unless you design a pass-through mode only converting the TTL to analog. But since I don't have one of these and I don't plan buying one I won't bother.

Hi retrocanada76,
would you be willing to update the firmware to support EGA cards with 16.000MHz pixel clock?
Here is an example of such a card and I'd guess there are other models too:
http://www.vgamuseum.info/index.php/news/item/467-udl-c3
Thanks.

Reply 323 of 341, by retrocanada76

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sorry I can't do it blindly. If I don't have one of these I cannot test. But this is something you can try yourself, just learn a bit about quartus II and how to change the PLL's. It's not that complicated.

Reply 327 of 341, by dJOS

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dr.zeissler wrote:

so does this little device "MCE2VGA" fully work for a Tandy 1000 (RL/HD).
I would like to use a TFT instead of my Atari EGA-Monitor.

Yes it does, I've tested it on my 1000 EX and it works great.

The impossible often has a kind of integrity which the merely improbable lacks.

Reply 328 of 341, by retardware

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Sorry for necroing.
But on Serdashop I did not find out yet whether this adapter can get my HGC card output and rescan it to, say, 100Hz?

I ask because I want to use a CRT VGA monitor for displaying HGC output.
So I am not yet sure whether this adapter is suitable.

Maybe for usage with CRT it is better to overclock the HGC and make a simple adapter like this?

Reply 330 of 341, by dreamblaster

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I received from photos from an MCE2VGA + Commodore 128 user :
He said : " Here's a few pix of some C128 screens processed by your cga -vga converter. 1-3 are basic8 images from the demo 4 is geos128 in 80 column mode. They look great. In order to get a good image I found that a small to medium res. 640X480 or 800X600 vga screen are the best bet for a stable attractive screen. I found the build quality on your rig top notch, real european high end."
Probably on a VGA CRT it would look even better.

demo 1 :

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Fair use/fair dealing exception

demo 2:

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Fair use/fair dealing exception

demo 3:

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Fair use/fair dealing exception

demo 4 :

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2480 views
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Fair use/fair dealing exception

Visit http://www.serdashop.com for retro sound cards, video converters, ...
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Thanks for your support !

Reply 331 of 341, by smbaker

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Hello,

I've been trying to get this thing to work with Convergent NGEN machine, and I was wondering if the author (@retrocanada76 ?) or anyone else here could answer a couple questions. I'm new to FPGA work, but I was able to get a mostly functional understanding of the code. The mce2vga works fine on my IBM 5150 with what I think is a HGC clone -- video output is rock solid in HGC mode. The convergent is a bit of an oddball, with a 19.980 Mhz dot clock.

I managed to modify the code to change PLL1's c0 frequency to 159.772 Mhz (eight times 19.980 would be 159.84 Mhz; 159.72 was as close as quartus would get). I think that's probably close enough, given the frequencies used by other adapters in the mce2vga code.

Now, the problem. There's this annoying "band of waviness" about 10% of the monitor in width. I can move the band back and forth with the phase button, but I can't get rid of it. I'm unsure where to go from here.

Scott

Reply 332 of 341, by Horun

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Am considering getting one of these since my old CGA/EGA MultiSync CRT monitor died, is it worth it ?

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. https://archive.org/details/@horun

Reply 333 of 341, by NightSprinter

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So, is there a reason why the background on a Tandy 1000 with this would be green? The device works, but I get a green background instead of black.

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Reply 335 of 341, by dJOS

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rmay635703 wrote on 2022-08-23, 21:42:

I wonder what would need to be modded so your device works with 15khz RGB+S (Analog CGA)

CGA is TTL RGB, not analogue.

The impossible often has a kind of integrity which the merely improbable lacks.

Reply 336 of 341, by dJOS

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NightSprinter wrote on 2022-08-23, 20:15:

So, is there a reason why the background on a Tandy 1000 with this would be green? The device works, but I get a green background instead of black.image.jpg

It looks like you’ve got a bridged pin on the main IC or some other fault.

The impossible often has a kind of integrity which the merely improbable lacks.

Reply 338 of 341, by rmay635703

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dJOS wrote on 2022-08-23, 21:45:
rmay635703 wrote on 2022-08-23, 21:42:

I wonder what would need to be modded so your device works with 15khz RGB+S (Analog CGA)

CGA is TTL RGB, not analogue.

RGB+S is definitely analog, Amiga and my QLT Futura 100 output an analog signal to a 15khz CGA monitor that can be switched between TTL or Analog .

Reply 339 of 341, by dJOS

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Yes RGBs is analogue, however CGA is RGBi and that is TTL, not analogue. Your monitor just has both sets of decoder circuitry.

The impossible often has a kind of integrity which the merely improbable lacks.