Mini-ITX inside Sega Genesis 1 (MK-1601)

[SiLo]

I was doing some garage cleaning and going through a few boxes of old stuff and came across my non-functional Sega Genesis 1 (MK-1601). I have a Genesis 2 that works but I always kept the Genesis 1 out of pure love and nostalgia. I hate throwing away stuff, especially things with sentimental value such as this, so I was thinking what could I possibly do with it.

I already have a PSP for my portable emulator needs so I can't say I was feeling like a Genesis portable was really something I'd want and use, so I got to thinking. I recently built an ITX computer for myself just as a desktop/server and it was neat having something half the size of a tower with an Intel Q6600 and 4GB of RAM powering it hooked up to a HDTV.

So I was thinking mini-ITX for this Genesis but I had some initial concerns regarding the fitment. Getting a motherboard and power supply in there was going to be hell I figured. I haven't opened it up yet to take a gander but judging from the initial look it was going to be interesting.

Enter the Zotac IONITX-A-U motherboard. That solved a lot of my problems. Nice speed, more than decent video capabilities, built-in wireless, and an external 90W power supply. The only concern I have is that it is a bit tall. Update: Zotac got back to me and said that the highest point is the heatsink, which is 1.2". The optional fan is 3/8".

The Genesis is about 11" x 2.2" x 8" WHD if I remember correctly. That should be good enough to fit this motherboard and a laptop SATA hard drive in there somewhere. I would like to integrate Bluetooth into it somehow too but that's just extra. As for the serial DB-9 controller ports in the front, I plan to use a properly-spaced USB backplate to substitute 2 front USB ports instead. I'll spray-paint the backplate black to keep the look and feel of the genesis, (same with the motherboard one).

As for ventilation, it looks as if this low-power chipset can handle passive cooling alone, but I might add some ventilation to the Genesis too. My main objective it to keep it true to the console as much as possible. I want it to seem stock at first glance. I was thinking of taking the fins on the left side of the case, cutting out the "lower" (non-raised) parts and bondo'ing a black wire-mesh grill on the inside to provide better air-flow. Maybe some 40mm fans if required but I do want to keep it quiet too, which the external PSU helps already with that. Update: Zotac got back to me and said that it can be passively cooled with the proper chassis ventilation.

There are a few cosmetic/functional things I was thinking about. First of all, the power switch. I want the power switch to work just like it did but that may require some interesting wiring. If that's not reasonably possible, I'll try to fit a horizontal red LED illuminated rocker switch in place of it.

The volume slider on the left of that... I don't see how I can integrate that into anything at all so that'll have to remain defunct. On second thought, I'd like to turn that into a SD/SDHC/MMC card reader if possible. Would be pretty cool to have SD card support on the front (vertical orientation) if possible. With the stereo input on the front, I'll probably just keep that defunct. I'd rather keep the audio stuff in the back or just use HDMI. One plug is better than like 4 snaking around anyways. I would like for the reset button to work as well but that shouldn't be too hard I hope.

I also would like the power LED to function as both power and HDD. When it is on, the power LED stays solid. When HDD activity occurs, I want the power LED to blink on the Genesis. I think this may require some electrical work. I have some experience but I am not really sure how to implement this but a relay comes to mind.

I figure this is the best community to come to with this type of project since you guys (and girls!) have the best experience with the console itself and modding it. I'd appreciate any caveats, tips, and suggestions!

[eagle5953]

Sounds like a fun project, and the Genesis mark 1 system case should be plenty roomy!

What are you going to use it for? If it's for gaming, even older games may require a beefier graphics card. I have a partially completed mini-itx project, and while I debated getting a low-profile card, I ended up saving space by using a full size graphics card that, with the right adaptor, lays flat above the motherboard (the card is upside down, in short). You may want to look into that.

If you do want to use the volume slider, why not just run the audio out through it first, before it gets to the back of the case? You'd have your volume set to maximum out on the computer and use the slider for control. While you are at it, you can set it up to use the RCA red and white audio outputs (internal splitter).

[SiLo]

I suppose that is a good question of what type of gaming I plan on doing. Granted, I don't expect to fit a gaming rig into the Mk-1601, but I would like to be able to games in general. I know Starcraft and Diablo II don't take much to play but when I think about Spore and possibly World of Warcraft (ugh), then it becomes iffy.

For the graphics adapter, I'm not exactly following you. Maybe a visual representation will help me understand better. The motherboard says there's a PCI-express 1x (mini) slot but I have yet to see it on the picture. Perhaps it is hidden behind the heat sink somehow?

The volume slider is a good idea, although I was thinking it might not be terribly useful if I am already going to use HDMI. However, in the case that I am not, it would be a nice option to use the front stereo jack. You mention an internal RCA splitter, but why would that be needed exactly? I was thinking most speakers already come with the standard 3.5mm headphone jack. How would I integrate the volume control? I haven't opened up the Genesis to see how they did it in the first place, so maybe it's an easy solution (I can hope?).

[eagle5953]

For the graphics adapter, I'm not exactly following you. Maybe a visual representation will help me understand better. The motherboard says there's a PCI-express 1x (mini) slot but I have yet to see it on the picture. Perhaps it is hidden behind the heat sink somehow?

Mine had regular PCI (ugh! sucks), and I found an adaptor that uses ribbon cable, so plug one end into the slot, the other end into your card, and then you can meneuver the card where you want it. Don't know if anyone makes one for PCI express, but I wouldn't be shocked. They also make rigid ones - probably cheaper, but less flexible.

How would I integrate the volume control? I haven't opened up the Genesis to see how they did it in the first place, so maybe it's an easy solution (I can hope?).

I figured it worked like any potentiometer. Don't know for certain, though. Never looked inside one.

Sentence fragments FTW!

[SiLo]

Mine had regular PCI (ugh! sucks), and I found an adaptor that uses ribbon cable, so plug one end into the slot, the other end into your card, and then you can meneuver the card where you want it. Don't know if anyone makes one for PCI express, but I wouldn't be shocked. They also make rigid ones - probably cheaper, but less flexible.

Oh nice! That's actually the most helpful thing I'd say in this case. I guess then it becomes a question of where to mount it and have the outputs exposed.

I figured it worked like any potentiometer. Don't know for certain, though. Never looked inside one.

That was my thought too but I was thinking of how it was integrated to the board and if I'd be able to simply reroute it through or at least have minimal wiring required. Since I'll be completely removing the original board, if it relies on anything from that.. I'll be SOL using that solution but possibly able to work a homebrew potentiometer.

[eagle5953]

Oh nice! That's actually the most helpful thing I'd say in this case. I guess then it becomes a question of where to mount it and have the outputs exposed.

Something like this guy... <- just found the first thing that looked like what I was describing. Didn't buy from them, can't tell you anything about how much the price will be, etc. Just using for an example.

That was my thought too but I was thinking of how it was integrated to the board and if I'd be able to simply reroute it through or at least have minimal wiring required. Since I'll be completely removing the original board, if it relies on anything from that.. I'll be SOL using that solution but possibly able to work a homebrew potentiometer.

That's true, it might be. Don't have one to check, though. If nothing else, you may be able to jury-rig something up that uses the slider...

[SiLo]

Something like this guy... <- just found the first thing that looked like what I was describing. Didn't buy from them, can't tell you anything about how much the price will be, etc. Just using for an example.

That's the term I was looking for, riser cards! Been a while since I've heard that term and "daughterboards" heh. Found something like this for PCI express 1x. Yeah, it turns it 90* so you can lay it in that direction instead, neat!

[eagle5953]

Yeah, that's the rigid type I mentioned. With those, you need to make sure it raises it enough - there's no flexibility once you buy it. They probably make them in different sizes (ie. 1 inch riser, 2 inch riser, perhaps a 1.5). Cheaper solution if you can make it work.

[SiLo]

I've taken it apart, cleaned it (not 110% yet, just a good wash down) and fitted some of the pieces in. It's going to be an interesting ride but I'm sure it's very possible.

Here are some pictures from the album on Photobucket:











As I had feared, all the components (power switch, reset switch, volume slider, headphone input) are all on-board. All the switches are simply just mechanical levers for the pieces on-board. Power LED was easy, it's literally an LED glued to the top with the leads hanging down and a standard 2-pin female connector to the board.

To make the reset switch functional I'll just need a simple tactile push button switch. For the power slider, I haven't figured out what I'm going to do yet. I believe the best option would be a momentary slide switch but those seem hard to find. I was also thinking about using the same kind of tactile push button switch for the power slider but I would have to have a button on both sides of ON and OFF.

Any suggestions? I'm trying to think how the Genesis itself handled it but it might have done like old AT switches did and carry the whole current load across the switch (dangerous!). I want it to be so that to turn the machine on, you need to slide it to ON. Once it is ON, you can turn it off by sliding it to OFF. It should work much like a normal ATX power switch but incorporating that into a slide switch seems to be rather difficult.

[SiLo]

Should be getting the parts in today, so this project can get underway this weekend!

It will work but won't be 'complete' until I get the stuff from Mouser.com to make the switches work with the Genesis housing.

I spend the last several hours working on a circuit diagram for making the power LED blink on hard drive activity while also being lit when there is none. Here is the diagram:



Using KTechLab, it simulates perfectly!

[impossiblescissors]

How is the mini-ITX Genesis coming along? I have a similar project in mind but haven't committed to a motherboard yet. I might consider a netbook or nettop motherboard if height is an issue.

[themadhacker]

[eagle5953]

He hasn't logged in since his last post.

Let it go man, it's gone. And don't bump old threads.