Odd FDS problem

[cr4zymanz0r]

Ok, I got a FDS today and I have an issue with it that i can't seem to find anywhere else talking about. Whenever I load a game the sprites are garbled. The rest of the graphics are fine, and even Mario and Luigi running around on the bios screen are fine, but once it loads up a game the sprites are garbled. They look like they have the right graphic content, but it's just picaso-ized and jumping all around within the confines of the sprite. I've tried 5 different games (3 different disks) and it happens on all of them. I've cleaned the cartridge contacts and even opened up the ram adapter and cleaned it pretty good with alcohol and nothing fixes it. All the games load fine, there's just this issue (and yes, cart games work fine). Does anybody have any ideas? I really don't want to pay a ton for shipping to return it back to Japan.

[ericj]

Try cleaning the magnetic read head with isopropyl alcohol. I assume the disks are official Nintendo disks and not pirate disks, right?

[cr4zymanz0r]

Well......i figured it out on my own, although that doesn't mean it's "fixed" yet

I have the FDS connected to my NES instead of a Famicom (since I don't own one). I made an adapter that essentially entailed extending a Famicom to NES cart converter with a floppy drive ribbon cable to get the famicom cart port out of the NES. Since it worked fine with Famicom carts i assumed it would work fine with a FDS RAM adapter. Well I got suspicious when I was testing the FDS on my 2nd NES and it'd lock up whenever the RAM adapter was hooked to the actual FDS (but was fine when they weren't connected). Well that NES was running on some cheap 3rd party AC adapter, but when I hooked the official AC adapter up from my other NES, the 2nd one worked but still had the sprite corruption. I ended up taking one the NES's nearly completely apart so I could connect a normal Famicom to NES adapter on it and then it worked fine, sprites and all.

Due to the whole AC adapter thing I'm assuming that the NES (or Famicom) actually does feed the FDS some small amount of power for something that the FDS batteries or AC adapter don't take care of. Basically, I need to fix my custom made adapter somehow (so I can use my FDS while my NES is assembled). I don't know if i could get away with just shortening the wires, or if I'd have to take all the wires out and put a higher gauge in. Also, maybe I could just replace the wires going to the 5V and GND pins with a higher gauge. Anybody with a more intimate knowledge of how the FDS interfaces with the NES/Famicom have any suggestions for fixing my adapter before I start trying to cut off all that hot glue i gooped it up with?

[nintendodork]

It would've been nice if you mentioned that in your OP.  Using the FDS on a toaster is a such a pain.  It can be extremely finicky, and can even depend on the adapter you're using (i.e; it may work better with adapter A than adapter B simply because it's different).  Not to mention the slightest bump will make it freeze up.  As far as the FDS interacting the the console it's attached to, the only way it does so is when the FDS's RAM adapter requests data from the Famicom, which requires no more power than a standard Famicom game.  This is why the FDS can run so long on one set of batteries.

[Xious]

Well, if you want to go totally overboard, you could circuit-map the RAM-Adapter and build a new one on a custom PCB that fits into a NES cart case...

The easier solution is to grab one of those HES Unidapter cartridge slot extenders and use it instead of trying to hard-wire a FC port to your NES, unless you are trying to add a port to the top of the NES or something. Some photos of exactly what you're attempting would be useful in diagnosing your problems...

If you want to work with what you've already created, read on...

I suspect that it is not simply a voltage issue, but the source of power to the RAM-Adapter may be part of the problem.

You should take V&A readings on the adapter you are using (the working adapter) and compare them to those on your wiring harness to see how they relate and also take readings on the leads going to the FC port and see if they are within the tolerances required by the RAM-Adapter.

Something is causing corruption of game data loaded into he RAM-Adapter's memory before the NES is reading it. You might want to try supplying clean +5V to the RAM-Adapter to see if that works, as this will tell you if you have something improperly configured.

-Xious

[133MHz]

Try this to rule out bad RAM inside the adapter first: FDS RAM Adapter Hidden Self Diagnostic

If the RAM is OK, try this instead: Weird gfx glitching issue when using the FDS RAM Adapter on a NES

[Xious]

Hmm...

He said that it works just dandy with a normal adapter, but not with his custom wiring harness.

If it was bad RAM, it wouldn't work with either, or I would have suggested that. It's still good info for this thread though, for those who need to do diag on their FDS.

Your other post however, nails the problem on the head. I suspect it's a data line issue in his wiring harness, which is fixable, but I have no idea how he's set this up and how long his leads are...

If he's trying to run the external FC port out of the NES too far, he could be suffering signal degradation from unshielded lines too. I considered adding a 60 or 72-pin port to the top of a Toaster and cramming an FDS inside of it to make a Toaster Twin system, but it sounds like he has a bare port laying on the table with wires from a PC FDD cable frankensteined to the NES cartridge socket from what I read here (above).

The split lines between the main cartridge port and his aux port could be part of the problem too. So may potential issues, and no precise idea what he's done, makes it impossible to debug.

-Xious

[i heart yuna]

buy a famicom?

[Xious]

That's what I usually suggest to people, but this guy seemingly wanted to make a custom system that handles both NES & FC games at once, like the Generation NEX.

Frankly though, as he hasn't bothered to reply at all, who cares at this point...

I could make what he wanted to build in about an hour, but I'd rather try to cram an FDS into a toaster just for shits & grins.

-Xious

[cr4zymanz0r]

Ok, i'll post a couple of pics for my adapter so everyone can see what I'm talking about.
All I did was take a copy of Gyromite with a converter inside of it, cut out a hole, and extend it with a floppy ribbon cable. I still haven't done anything new to it yet though to try to fix the sprite corruption yet, but I'm going to start on cutting and splicing the cable back together to make it about 6 inches shorter.

[Xious]

Alright...

You are easily suffering from signal noise and degradation here. }f you want to do a cable this long, you'll need slightly heavier gauge wire, plus you'll need to shield the lines in sections and them put an over-shielding on them.

I would guess that you may have a cold solder join or a solder point on the connector that bled over onto another contact, but it's impossible to tell without seeing your soldering work, inside the case and into the adapter.

You'd really have better luck cutting a hole in the top of the NES and wiring a 60-pin connector into its top. If your goal is just to use the NES with the FDS and you don't care about looks, then pick up a HES Unidapter, or any other long cart slot adapter.

If you want to go with the route you are using, you'll need to check every connection, or just redo them. I suggest mounting the 60-pin connector on a prototyping PCB, then soldering the wires to its pins on the PCB or bridging them (better), which will allow you to make any requisite tweaking to it on the PCB itself, such as adding resistors. Soldering the lines directly to the connector is a sure-fire way to enter 'diagnostics hell'...

-Xious

[cr4zymanz0r]

I don't really want to make a Famicom cart slot built into my NES. I try to keep from modifying the outside of my consoles. Now if I had the tools, parts, and were much more capable of doing a very professional looking job with a matching cart dust flap (like SNES, etc.) then I might would consider it. However, I know my real world end result would look much more frankensteined. I know you're probably thinking the same thing about my adapter I made, but it can be removed when not in use  .

Now I tried to take the easy route on fixing my adapter because I didn't want to have to get all that hot glue off, desolder all the wires, buy thicker wire, then solder that all on. Instead I just cut and spliced this wire to make it 6 inches or so shorter where the cart connector isn't coming far at all out of the game cartridge. Well that took far longer to do than I anticipated and now the sprite glitching is far less prevalent, but still there  .

I'm kinda sick of messing with it now so I think it'll probably go on a long hold. Also, do you know of a good place to buy a HES Uniadapter? I looked around briefly but couldn't find anything. If the price is decent on those I might just buy one instead of spending a ton more time on my custom adapter.

[Xious]

I can probably find a Unidapter for you if you wish...Do you have a budget for this?

If youprefer to send me what you made, I can rework it to be functional. Send an extra NES cart (of any kind) along with it. Something common and cheap, or an extra case, or order a case from ReteoUSB and i will make it nicer looking znd debug it in the process.

If you send the RAM-Adapter with it, I can hardwire it to the board and resolve any possible future issues as well. I only have enough RAM-Adapters for m y drives plus one extras that I plan to mod, or I'd use one of my own.

-Xious

[cr4zymanz0r]

About how much do you think the Uniadapter would be? Also, Id probably prefer to fix my adapter myself but i'm up for suggestions and such. What gauge or kind of wire would you suggest? I'd prefer something I could just run to Radioshack and get since it's less than a mile away. Any other tips besides the obvious ones like make good solid solder connections?