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martinw
March 25th, 2017, 07:55 AM
37290

Martin

RizThomas
March 25th, 2017, 09:40 AM
how did you interfaced the CGA to the monitor. BTW--nice

3pcedev
March 25th, 2017, 03:03 PM
Using a composite video to HDMI adaptor would be my guess

martinw
March 26th, 2017, 12:16 AM
It's a merry mixture of bits and bobs, I'm hoping to put them in a neat little box at some point.

37318

A Commodore 128 video DAC RGBI to RGBA adapter.

A GBS8200 RGBA to VGA converter.

And finally a VGA to HDMI converter.

I already had the 4K monitor from something else I was working on :D

Martin

paperinik77pk
March 26th, 2017, 10:19 AM
It's a merry mixture of bits and bobs, I'm hoping to put them in a neat little box at some point.

37318

A Commodore 128 video DAC RGBI to RGBA adapter.

A GBS8200 RGBA to VGA converter.

And finally a VGA to HDMI converter.

I already had the 4K monitor from something else I was working on :D

Martin

Good work! It is a very nice solution!...I think I am going to adopt it! :)

martinw
March 26th, 2017, 10:23 AM
Thank you, feel free to adopt, it seems to work well :cool:

Scali
March 26th, 2017, 10:44 AM
That's exactly the plan I have. I have the GBS8200 and the VGA-to-HDMI already, still waiting for the C128 DAC.

Great Hierophant
March 26th, 2017, 10:51 AM
It's a merry mixture of bits and bobs, I'm hoping to put them in a neat little box at some point.

37318

A Commodore 128 video DAC RGBI to RGBA adapter.

A GBS8200 RGBA to VGA converter.

And finally a VGA to HDMI converter.

I already had the 4K monitor from something else I was working on :D

Martin

Now all you need is an HDMI capture device, and profit!

Where did you get the C128 DAC adapter?

Flamin Joe
March 26th, 2017, 06:15 PM
I brought one of these kits a while back which does pretty much the same job and comes in a nice case. If you already have the GBS8200 like I did, you just need to purchase the "short form + case".

http://www.microbeetechnology.com.au/vga-video-converter.htm

Works great for quickly testing CGA/EGA PC's and the Amiga on my workbench VGA LCD.

njroadfan
March 26th, 2017, 07:12 PM
I've got an OSSC on the way, I'll let you know how it does with vintage computers as opposed to game consoles. Removes the extra D/A to A/D conversion in the chain as it goes from RGB direct to DVI.

Have you tested the amount of input lag in this setup? The CGA DAC shouldn't add any, but the GBS and HDMI converter and any upscaling done in the monitor will.

Xacalite
March 26th, 2017, 07:20 PM
But you can disable scaling, can't you?
CGA graphics is meant for 4:3, not 16:9.

njroadfan
March 26th, 2017, 07:25 PM
A video upscaler can scale and maintain the original aspect ratio. Some monitors default to stretching all incoming video to 16:9, but can be set to 4:3 mode manually.

pearce_jj
March 26th, 2017, 11:18 PM
I was wondering recently if 4K is enough to add convincing CRT rendering.

martinw
March 27th, 2017, 12:24 AM
That's exactly the plan I have. I have the GBS8200 and the VGA-to-HDMI already, still waiting for the C128 DAC.

http://www.ebay.co.uk/itm/Commodore-128-Video-DAC-RGBI-to-RGBA-Adapter-by-Digital-Audio-Concepts-/322451949133

martinw
March 27th, 2017, 12:26 AM
Now all you need is an HDMI capture device, and profit!

Where did you get the C128 DAC adapter?

http://sharewareplus.blogspot.co.uk/2016/10/commodore-128-rgbi-to-rgba-adapter-by.html

KenEG
March 27th, 2017, 06:01 PM
There is now a guy on eBay selling cases for DAC with Gonbes. I just mine today. Hope to put my components in it soon.

bobba84
March 27th, 2017, 06:04 PM
I was wondering recently if 4K is enough to add convincing CRT rendering.

That would be cool!

knightserrand
June 20th, 2017, 09:47 PM
Is there a solution similar to the Commodore RGBI -> RGBA adaptor that works with EGA? I know that the EGA signal has different intensity bits for each color, making this more difficult.

Trixter
June 22nd, 2017, 08:53 AM
Nobody has currently tackled that as a project, probably because VGA cards can output the same video modes as EGA, and VGA connections are very common and widespread. I tested EGA 640x350 output from my VGA card connected to a VGA-to-HDMI converter and it was able to display the signal just fine.

Gfbtdhg1
June 24th, 2017, 07:49 AM
That's great 😂. What is that "sysgen" drive thingy in the computer?