Glitchy sprites on FDS

[zmaster18]

http://www.ebay.ca/itm/20PCS-Thick-Film-Network-Resistor-SIP9-4k7-4-7K-Ohm-NEW-Array-Resistor-/351588185762?hash=item51dc49f6a2:g:xjAAAOSwHQ9WVWJ4

^ These were the exact ones I have. If you're in a hurry to buy them, I can sell them to you and have them shipped to you faster for cheap.

[zmaster18]

Hey everyone, I'd just like to confirm that the revision of RAM adapter FMR-02 also has the glitchy sprite problem. The board looks just like a FMR-03.

I also got a second RAM adapter that doesn't boot the game after it loads and stays stuck on a black screen. I have no idea what to do with them, but my guess is that their RAM chips might be bad? If anyone wants to take a look at it, for science's sake, let me know.

[P]

The resistor array fix doesn't do anything for it?

[zmaster18]

I haven't tried it on the non-booting RAM adapter, it just seems like a different problem altogether.

[Whiteboy]

Hi everyone,

Just wanted to let people know that I have now also done the resistor array fix for my version 3 RAM adapter. Thanks to zmaster18 for posting it to me!

This was my first time ever soldering. Many near-misses and almost burnt my hand... I don't recommend doing this after having a cider...

Anyway, the pics might look a bit messy but I did clean the connections up a bit afterward. When I tested it, at first nothing had happened and the glitch sprites were still there. I was just glad the thing was still operational.
But then I re-soldered a connection that I guessed wasn't that well made, tested it again, and now it works fantastically with all my games! Works with FDS Stick too. One happy gamer here If I can do this with no experience and slightly intoxicated, just about anyone can 

I'll post an update when I get my AVS NES and original Famicom. Right now all I have is a Japanese A/V Famicom.

[pikasurf]

Sorry for digging this up from the grave.

This is more of an informational post

I am having this problem on my NES front loader. The following values all have shown visual improvement (I don't have O scope). In all cases I am using a resistor array on a -04 ram board. My test condition is the second level of Castlevania, both on a disk and the FDSstick.

3.9k
4.7k
5.6k
5.1k
6.8k
10k

Update 11/21: Tested on a second NES (1st unit is a -08 NES second is a -11), No Change
Tested 10k, no change
Still waiting on the smooth ram adaptor, and I forgot to order a 3.1k. I have a Hi Def NES I need to install, I might install and see if there is a change.

Update 11/27: Hi-Def NES fixed it, however I had the game "crash" in a complete glitch. Could not get the FDStick to work either (audio only, no video). Worked with an actual FDS. Need more time to play around.

Update 12/03: I've bought way too much Nintendo stuff. Glitchy ram adaptor is working on the Hi-Def NES as long as I am using a FDS, not FDSstick. I suspect a power issue. Glitch Ram adaptor is working on a Top Loading NES, and an RetroUSB AVS. My smooth ram adaptor is currently MIA. I may or may not update this post again

i have a hi-def modded av famicom and 2 rev-03 ram adapters. in composite mode: everything plays fine but i get glitchy sprites with both the fdsstick and a real fds, on both adapters. in hdmi mode: everything crashes, including the real fds on both adapters

[fredJ]

I got my resistor arrays in the mail the other day and soldered them into 6 glitchy RAM adapters. They all work perfectly now! This method works  

According to my colleague, the fix forces the correct values into the console, so it is a pretty good fix to do. Also because it is quite difficult to test a RAM adapter on every possible problem console.

[zmaster18]

Would your colleague know how to fix RAM adapters that simply don't load the game? I have 2 RAM adapters that work fine, load the game, get the black screen with Nintendo copyright text, followed by a black screen. The game doesn't boot after that.

I suspect it's a RAM chip issue, but I really don't know. I'd be willing to mail the adapter to you guys, for scientific research. 

[P]

My very limited knowledge of digital logic is that when you attach a resistor between a data line and ground like this, it's called a pull-down resistor. It makes sure that voltage is 0 V when nothing is connected (the game is sending 0s) to the data line. Otherwise it's possible that it sometimes reads the 0s as 1s and things gets messed up.

A wild guess is that if some of these data lines that are crucial for anything to be displayed at all, it could be enough that that one gets the wrong value for nothing to work. In other words, maybe the pull-down resistor array is worth a shot on those non-working RAM Adapters as well.