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Amiga 1200: Indivision AGA MK2cr

After toying with video output on the Amiga 1200, I'd come to the realisation that old technology just wont display well on brand new TVs. Due to this I therefore researched what everyone else on the interwebs did to get a better resolution from these old beasts.

Results came up quickly and all signs pointed to this device, the Indivision AGA MK2cr by Individual Computers (buy it here.)

This device piggy-backs onto the Lisa chip (the Amiga's Video processing chip), taking the output and then using it's own CPU to convert this to a more recent standard that newer TVs and Monitors can reproduce. It has upgradeable firmware and configurable options. It's stated that, out-of-the-box, you won't need to configure a single boolean value to get it running.

The price isn't low.. but all the reviews I'd read indicated that the value for money ratio was high. I therefore set out in pursuit to find one and came across some hits on Amibay, but watched as faster hawks snapped the prey up VERY quickly.

eBay showed some results also; and then it happened... the exact seller of whom I bought the 1200 from provided the device up for sale. I couldn't resist... Steve understands eBay and had treated me perfectly on the previous sale and so I grabbed this item. Turns out I got a few extra bits too, of which I'll report about later.

Unboxing

The item arrived in record time and it felt like Christmas had come early once again. I knew I had to take my time with this though... opening a ~30 year old piece of equipment (although you could tell it had previously already been modified) required patience and a steady hand.

The box came with all the required components. No software is provided as the device works primarily via its own firmware to detect the video signals being produced by the Lisa chip and convert them out to DVI-capable resolutions.

Installing it

All in all, this was a piece of cake. As mentioned, this Amiga 1200 had been toyed with before and so there was no hassle of breaking warranty seals and the like. Case screws were undone and then the top plate was removed.

I'd previously wondered what the extra DB-25 port was on the left-hand-side (as you look at the back of the machine) and this became clear on opening the case. It's a SCSI port for an accelerator that contains a SCSI interface. As you can see, no such accelerator is in the slot, so the internal end of the cable was sitting loose.

Over near the Lisa chip, I found the CF card to be sitting directly above it. Turns out that there's enough clearance above the MK2cr to have the CF sitting on top, so I unstuck it, flipped it over and stuck the new hardware in place. This went on with a nice click. Even pressure was applied to the center area, where the 4 holes are. Once in place, the cable was run (very tightly, it's the perfect length!) to the location where I'd removed the SCSI plug. Fortunately, I received a 3D printed plate to hold the DVI connector in place. I did need aftermarket screws to secure the plug in the housing; the nuts that were removed from the end of the DVI plug weren't long enough to go through the plastic plate.

First Impression

This always counts... this device was marketed as 'no configuration' ... reminds me of the old 'plug-n-pray' days. Sometimes I miss ISA/EISA cards and their jumpers of which I had supreme control over. Anyway, I hooked up a cheap VGA cable via a DVI-to-VGA adapter and plugged it into the TV. Powering it up... I nearly cried.

The ghosting was immense ... and I truly wasn't expecting this from a Digital product. A quick google lead me to believe that the DVI-to-VGA and then the VGA cable were trashing the signal. I also noted that the resolution being output was 1280x1024. That's a great resolution; but a shitty VGA cable might have issues. I quickly tested the shit VGA cable and adapter on a VGA monitor... it looked better, but still not up to the standard I was expecting.

So, I opened the warchest and found a chunkier cable that had a DVI on one end and a VGA on the other... on the LCD Monitor still showed minor ghosting, as follows...

But on the TV, the ghosting was hardly noticable... Score! This is the pixel-for-pixel that I was looking for.

At this stage I was content with the output... It has since occurred to me that I could convert the DVI to HDMI and keep the signal totally digital. I'll try that and report back soon.

Configuration Options

The 'overscan' area can be customised. On bigger screens, it will default to the background colour of Workbench. You can confgure this using BorderBlank.

Next, resolutions. The MK2cr supports the 'HighRes' driver. Download it here. To install it, move the HighGFX file from the archive to your "sys:devs/monitors" directory and reboot. Higher resolutions should now be visible in the ScreenMode prefs.

If you want to toy with the devices configuration itself, then firstly grab the Flashing tool and v2.6 firmware to see if you have the latest installed. Once you're up to date, you can use the v1.5 Config Tool to configure the device.

From what I understand, you choose the mode on the left and then re-map it to a resolution from the VGA column. Then hit Test/Use/Save. Will update when I tinker further...

The resolutions are awesome. You can find the HD720 driver in the HIGHGFX package, drag that to your dev/monitors folder also. I switched my TV to 16:9 scaling and the resolution looked great!

Time for model train controller programming and games!