Category Archives: Interference

Pixel Perfect

VGA and DVI-I/HDMI video output with Indivision AGA MK2cr


I’m happy to be the owner of an old 14″ Commodore 1084s-D1 monitor which is perfect for retro Amiga gaming, but using the Workbench in higher resolutions is another epilepsy inducing story.

Sadly, the said monitor has not fared very well the past few decades in storage, and shows the expected symptoms of the old-age.

I might try to do some work on it at some point, but I’m afraid that the problems are not resolved by just simply replacing the capacitors. Replacement part(s) might be quite hard to come by.

Anyways — I came across this little device Indivision AGA MK2cr. It is basically a flickerfixer/scandoubler which can be fitted over the A1200’s Lisa chip.

It captures the signals and converts the video to digital (DVI-I) and analog (VGA) signals.

Maybe I can make due without the old barrel sized CRT monitor after all?

I ordered this directly from Individual Computer’s web shop.

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The Indivision AGA MK2cr
The LISA chip
The LISA chip

Installing it doesn’t require much — no excessive force needed,  just enough push to get a firm grip on the chip.

Plugged on top of the LISA
Plugged on top of LISA

The cable can be easily routed under the floppy drive, and thru the A1200’s empty trapdoor. The backplate can be modified to house the DVI connector.

You can also purchase a separate DVI jack compatible backplate.

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It all fits quite nicely

Closing the hood and giving it a try.

First — the VGA output.

VGA
VGA signal output

I noticed quite horrible ghosting (not visible in above photo) and interference in the analog VGA output.

Similar issues are apparent in the digital signal.

Digital DVI output
Digital DVI output

My monitor is definitely not a quality one, and I’ve had issues also with my Mac, PC and PS4 — nothing this severe though.

I downloaded the AGA MK2cr’s config tool and available cores to check all the configuration options.

There seems to be quite many options to tune 😉

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Indivision AGA MK2 Preferences

First thing I did was to remove concurrent output of both VGA and DVI signals. I switched to use only VGA.

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Output options

That got rid of the major interferences in analog VGA signal.

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Clear VGA output

The video output is actually crystal clear, the photo above doesn’t really do it justice.

The DVI digital signal problems are not completely sorted out yet, but I will give it a try with another monitor or TV.

I believe that my monitor just doesn’t support the current HDMI signal setup — I need to continue tweaking the config tool.

People have also shared their AGA MK2 configuration files, which might solve the few problems I have noticed so far — like the not-so-smooth scrolling and problems in centering the screens.

This seems like a good 50hz  config for gaming.

Check out this guide also.

This configuration is also worth giving a try.

I’ll probably post my configuration here in the future, or a link to the one I have found most optimal for my setup.

Conclusion

I was hoping to have a fit-for-all solution with AGA MK2cr, but instead I’m reading thru endless forum threads dwelling into mysteries related to the configs and esoteric PAL/NTSC screen problems.

Sadly seems that the vendor has obviously given up on improving the configuration tool.

I’m going to give this a proper try — getting stuff like this to work was not supposed to be easy, right?

I can always fall back to the SCART option for gaming purposes.

Update 8.11.2016:

I have managed to get a decent setup for casual Workbench use.

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Nice and spacious Workbench desktop

See monitor drivers for the SuperPlus and HighGFX modes – packages available here and here.

I’ve had good experiences with HighGFX with 1024×768 resolution, but seems that some Amigas work better with higher graphic modes than others.

My setup start to flicker quite badly after 5 minutes from the initial cold boot. The flickering  goes a way completely after about 10 minutes.

Go figure.