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Santa Cruz, California

DISCOVERY!
I didn't try all of my games (forgot the ones in my backpack).
Apparently it has something to do with batteries and the save feature.
When I plugged in Link's Awakening and my Pokemon games, the same thing happened: The "Nintendo" came down, BLING!, and then NOTHING.
Seriously guys, I have no idea what's going one here. Help me out.

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Tetris is just a 32kb rom, no memory bank controller. Pokemon is MBC3 + Ram, links awakening is MBC5 + Ram. There's just some bad wiring somewhere, time to whip out the continuity tester!

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Santa Cruz, California
Apeshit wrote:

Tetris is just a 32kb rom, no memory bank controller. Pokemon is MBC3 + Ram, links awakening is MBC5 + Ram. There's just some bad wiring somewhere, time to whip out the continuity tester!

Thanks man. I figured my ribbon cable thing went WAY too smoothly.
I'll let you know what I find out.

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You may also run into issues if your wires are too long. But the fact that Tetris is working seems to indicate that it's a wiring issue.

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I was actually going to ask if the long wires could cause an issue but I'm not an electronics guru so I didn't want to come off as stupid.

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Santa Cruz, California

There was a wiring issue. I found a solder bridge between pins 15 & 16 on the board side of the ribbon cable.
I'm also going to shorten the cable by several inches (I had left it long just in case something like this happened).
I'm gonna cross my fingers and solder this pig back together.
Wish me luck.

Last edited by Teh D3th St4r (Feb 6, 2013 8:40 am)

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San Diego

From what I've gathered reading on other builds you can also use smaller gauge wire to help with that issue. I know a few things about electronics but I've never made something like this before nor do I remember the mechanics behind why it would work. If all else fails it's always worth a shot though.

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Santa Cruz, California

*sigh* I rewired the whole thing. Still doesn't work, but there is progress: Both Pokemon and Link's Awakening bleep and bloop before not booting.
Again, the only games that don't work are the ones that have a memory bank. I guess the wires are too long.
Well, this complicates things a little bit. Not sure how I'm going to solve this one... guess I'll go study some DMG schematics (it's probably something stupid/simple that I overlooked).

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Santa Cruz, California

Okay, here's some happenings of untold weirdness:
I went over ALL of the connections, implementing visual and electrical inspection... no issues found.
I re-soldered all of my work. I literally took everything apart and reassembled it.




When I put everything back together, it still wouldn't boot LoZ, Pokemon, or LSDj...
I was getting ready to go to bed, and decided I would sleep better if I installed my rocker switch and completely assembled the keyboard. Just for the hell of it, I plugged in Zelda and flipped the switch.
For no apparent reason, Link's Awakening started... it was glitchy, but it was working. Here's the thing: it only works intermittently, and I can't actually play the game. Every time I try access the stored data, it freezes, crashes, or restarts.

I'm thinking that my motherboard might be the problem...
Thoughts?

Last edited by Teh D3th St4r (Feb 6, 2013 10:12 am)

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I remember on the benheck forums people who did mods involving extending cartridge slots weren't using a large enough gauge of wire and had similar issues you did when making portable consoles. Perhaps you need to use some slightly thicker stuff? Other than that, you may want to try rewiring the cartridge slot again just in case you accidentally mixed some wires up.

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Tokyo, Japan

Forgive me for being utterly clueless but why would the gauge of wire make a difference?

Also, I just checked in on this thread, it is absolutely bad ass! I mean this as high praise but I love the "fuck knows if this will work or not but im doing it anyway!" kind of vibe. Is there a final planned feature list?

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Murcia, Spain

@Lazerbeat I'm not an expert on electronics, but from my personal experience I can say that thebitman has a point when he says that the gauge of the wire matters.

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In my very limited experience with hardware I have found that devices with parts soldered directly to the main PCB have trouble operating when they are distanced too far. It could be a matter of carrying the signal, the wires not being sheilded and there being some sort of interference, and sometimes tiny wires short out due to bending. These all can happen with larger gauges too I suppose, but I guess someone could explain this better than me.

It's stuff like this which is why video cables like VGA and HDMI can be only so long before you have to use a signal repeater, I think. Signal loses integrity after a while. I think that a larger gauge of wire might be a better carrier since repeating isn't an option. Perhaps a more skilled electronics guy than myself can lend a voice?

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Murcia, Spain
thebitman wrote:

In my very limited experience with hardware I have found that devices with parts soldered directly to the main PCB have trouble operating when they are distanced too far. It could be a matter of carrying the signal, the wires not being sheilded and there being some sort of interference, and sometimes tiny wires short out due to bending. These all can happen with larger gauges too I suppose, but I guess someone could explain this better than me.

It's stuff like this which is why video cables like VGA and HDMI can be only so long before you have to use a signal repeater, I think. Signal loses integrity after a while. I think that a larger gauge of wire might be a better carrier since repeating isn't an option. Perhaps a more skilled electronics guy than myself can lend a voice?

There are many variables which we do not take into account when we just "short two points" of a circuit, but in this case it's not just a circuit. If you add wire of a certain length, other phenomena appear, like attenuation, impedances adaptation... Any of these things could add problems.

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Santa Cruz, California

After carefully reviewing pretty much every DMG schematic on the internet, I think I can safely say that the length of the ribbon cable has nothing to do with my problem. After consulting my old man, I have come to the conclusion that what's happening is there's some contact problem along the system, and the higher addresses aren't being accessed.
For example; here are some of the games that don't work at all (save for Zelda, but that can't be played, so we'll call it "not working")

Here's an example of address lines not being accessed. Gex plays just fine on my gaming DMG.

But when it's plugged into the keyboard, it glitches heavily, and doesn't boot.

Now here's some games that play, but are heavily glitched (graphically). Again, they play perfectly fine on my gaming DMG, but look hella messy on the keyboard. Ninja turtles is interesting, as it plays just fine until a bad guy is on screen, then it freezes and dies.

You little bastard. What are you hiding in there?

I suspect that I may have warped the old cartridge port or the pins while working on this thing (I've been bending pins and soldering on it A LOT).

So, I'm just going to replace it. We'll go ahead and use this Prosound DMG. Don't worry, it's the first one I built, so the mod isn't that great, and it's parts are going to the greater good.



I have this weird feeling... like I've done this before...

Okay. Let's test it...

Hmmmm... so, now it won't make it past the BLING! This is kinda interesting. Well, I'm already through the rabbit hole on this one. Let's swap motherboards!


This morning feels like constant Déjà vu.
Let's try it out.

Damn... more of this bullshit.
Time for lunch and then I'll check my wiring. I suspect this hangup is actually my fault.

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Santa Cruz, California

UPDATE:
So, yeah, I crossed a couple of wires... LSDj still won't boot. I'm going to eliminate the ribbon cable, and try some heavier gauge wire.