Cuzza's Sega SC-3000H Nano-ITX Mod

Here's the old Sega in all its glory:



Some info:

The SC-3000 is a computer based on the hardware of the first videogame system released by Sega in Japan : the SG-1000 series. It can use the same game cartridges marketed for these consoles.

The SC-3000 Computer was released in 1983 by SEGA in Japan. It became a competitor of many others 8 bit based computers and its popularity was different in each country it was introduced.

It was mainly sold in Japan, and two important overseas market: Australia & New Zealand. It has found a little distribution in South Africa, Italy and Spain. Probably there were also some sales in other countries but very little is known about this computer and it is difficult to find out precise information.

This one is stuffed. So I plan to rip out the guts of this thing and put something useful inside, namely a nano-itx board and supporting hardware. Stay tuned....

So, first thing I want to know is can I get the keyboard to work?

I think so. Can use one of these:


This guy gives you an idea of how it will work.

Some more web searching led me to the key matrix for the Sega:


Pulled the kb off, it connects with some nice green ribbons:


So I took the keyboard right to bits to see which connection on the ribbons goes where. Then put all the info together, this is the plan:

h3llb3nd4 said:

wow that is complicated!!
G/L man! can't wait to see the end product!!

Click to expand...

thanks bud. keep watching, i'm going to need moral support when time comes to buy the parts

Here's the news: New Zealand is pretty light on retailers/etailers/suppliers/anyone who I can buy the nano-ITX stuff i'm going to need for this project. And the ones who do often charge extortionate prices so I think that some complicated international ordering is going to have to happen here

Back to proceedings; now I always love reading other people's detailed project logs on TPU so I'm going to try to be in-depth here to pay that one forward as it were. I hope you guys like it.

Here's the Sega with the keyboard off:



Note build date 1983, same age as me, even has the same initials, SC! I think this was meant to be.

Here it is in bits. I threw the old circuit board out, it was stuffed, salvaged a couple of the headers (I need the keyboard connection ones) and some resistors that was about all.



Now, what can I fit in here? Made some quick templates to see what will work?



Mini-ITX it seems is possible, but very VERY difficult, because the case narrows so much at the front:



So the board would fit but the heatsink would not, nor would the memory module. The heatsink could be swapped for a heatpipe latop jobbie, that would work but how to make the memory fit? Are 90deg DIMM risers available? I couldn't find one low enough. I know someone who's posted here who likes resoldering motherboards, maybe he would like to solder a bunch of floppy cables to 240 pins beneath the board and mount the DIMM slot somewhere else (as a personal favour).

No, I think that idea is just crazy. I mean the guy ansking this question seems to have been working on it for 7 years and failed. So I'll go with Nano-ITX instead.

MKmods said:

you could mount the mobo upside down below the keyboard (sticking out the bottom with a bit taller feet)

Click to expand...

mlee49 said:

What if you mounted the M-Itx upside down?

damn it, cut off my MkMods. good thing he's here to help, I'm afraid I suck.

Click to expand...

Good idea, had not thought of that. but it wouldn't help, the keyboard atcually takes up more space inside the case that the pictures show, so the board's appendages would still hit the other side. I will keep the suggestion in mind!

On a posting mission here, so I'll post some more.

Here's the Nano-ITX board I'm thinking of getting, Via's EPIA-NX




Great thing about it is everything is very low to the board and all the connectors plug onto board headers, so I can mount them easily into the side of the case no matter where I mount the board.

Now some people have suggested I get one with an Intel Atom. That sounds like a pretty good idea, but I haven't found an Atom board with the same packaging flexibility of this one. (actually I haven't looked very hard, I think there's a Via fanboy deep within me somewhere, lol).

Still wide open to suggestions here, so fire away if you have any.

Cuzza

MKmods said:

here are a couple shots of the Via EPIA PD... Notice the ps mounted in the background, very low profile (especially for 200 watts)

LOL, I just priced the Epia Nano

Click to expand...

No memory on that board? Audio plug connector is too tall anyway!

Oh yeah, not cheap, but hey, as far as the internet can tell me, no one has done this before. So I think it's worth it to break new ground.

EDIT:

Have found a New Zealand retailer for this Via board. NZ$607! = US$382 oh noes...

EDIT 2:

I see idotPC ships international. Will see how much that charge is...

I'm a bit stuck here

These are the headers off the Sega board which the keyboard matrix ribbons plug into



Now the ribbons go into these and then I need to connect the pins to the floppy cable somehow. I don't want to solder the wires directly onto the pins. Any suggestions?

Progress....

Hey team, here's what I've done today.

Realised the original key diagram was wrong. Updated:



Managed to answer my own question of how to connect the keyboard ribbon headers, by making an adaptor board. This will also save connecting the floppy cable wires individually. here's the plan:



Nice pretty picture. Easier drawn than made though! Went and bought some bits and set to work soldering. I have never soldered a circuit board before so I quickly found my technique left a lot of room for improvement, but four hours later it was done:



And the bottom, not so pretty!



It all works though; I tested all the connections with the multimeter, everything seems just fine. Here it is connected:



Phew, it has been a hard day to produce that, and my room is a mess! I have too much time on my hands. Luckily my assistant is working hard....



Damn, I am totally committed now, no excuses. Things are looking good on the job front so I should be able to afford the bits I can't make.

Peace out
Cuzza