EverDrive Forum

General => EverDrive N8 => Topic started by: evil_ash_xero on May 16, 2014, 02:22 AM

Title: White dots on screen
Post by: evil_ash_xero on May 16, 2014, 02:22 AM
I have a very annoying problem with my N8. In fact, I have 2 N8s. One from KRIKzz, and one from Stone Age Gamer. Both have this problem.

It's hit and miss. Sometimes I'll put the cartridge in, start a rom, and everything is fine. But about 1 out of every 5 times, there will be these white dots littering the screen. Sometimes they don't pop up until the game starts, and sometimes they start on the black menu screen, before I choose a rom. If I hold "reset" on the NES 101, the dots will disappear. It's very strange.
I had thought maybe It was a connector issue, and I would pull the cart out, and put it back in. I have found that if I just press reset, that it has the same effect. Like I can have the cart in, the game will have white dots, press reset, and everything is fine. Do it few more times, and then the white dots come back. It doesn't really seem to have much to do with the connectors.

I have not had these problems with a normal NES game.

I have tried two different RGB cables, two different power supplies, and two different CSY-2100s, to make sure there wasn't a problem in the chain.
I've tried different OS, back to version 7, and up to 9.1.

But same problems.

Any idea of what this could be? I have a NTSC NES 101, that has the NESRGB mod. Like I said though, I haven't seen these issues with any of my regular cartridges up to this point. And I have been testing them quite a bit.

UPDATE: Here's a pic.

(http://i62.photobucket.com/albums/h97/evil_ash_xero/IMG_6117_zps76d5eeef.jpg~original)
Title: Re: White dots on screen
Post by: evil_ash_xero on May 21, 2014, 07:55 AM
Jason from Game Tech has been working with my EverDrive, and is seeing the same problem, but can't figure it out.

Here's a link to the vid. Any ideas Krikzz?

https://www.youtube.com/watch?v=Hv0PaVGeTv8&feature=youtu.be
Title: Re: White dots on screen
Post by: Kyle on May 21, 2014, 07:03 PM
Fun story. I have two RGB top loaders done by Jason and get the same thing. Doesn't happen on retail carts. I have a PowerPak and was having similar issues with it. It did it in game and not at the menu. I don't know if it is Krikzz's problem unfortunately. I normally just power cycle until it stops which seems silly given the amount of money I have in this.
Title: Re: White dots on screen
Post by: magnus87 on May 21, 2014, 09:31 PM
I like that background with stars  ;D

Good Luck!
Title: Re: White dots on screen
Post by: Enzo1960 on May 22, 2014, 10:36 AM
Have you checked these EDN8 on a regular (not RGB) NES?
Same problem?
Title: Re: White dots on screen
Post by: evil_ash_xero on May 23, 2014, 12:26 AM
Yeah, I have a non modded NES, and it does not do this with it.

Fun story. I have two RGB top loaders done by Jason and get the same thing. Doesn't happen on retail carts. I have a PowerPak and was having similar issues with it. It did it in game and not at the menu. I don't know if it is Krikzz's problem unfortunately. I normally just power cycle until it stops which seems silly given the amount of money I have in this.

Two? Which batch of NESRGB did you get? I think we're at the 3rd now. I got mine from the 2nd batch.
And I feel the same way. The top loaders plus the NESRGB..plus the modding...and then the N8s....lots of cash.

And considering the price of so many NES games, a lot of us who are willing to pay for the NESRGB, are also going to be getting flash carts. And to have this issue...it sucks.
Title: Re: White dots on screen
Post by: Kyle on May 23, 2014, 12:46 AM
First batch before the ram issues. I had a PowerPak and ordered an ED to see if it would do differently. If I had to wager a guess I'd say it's the power consumption from the flash carts. It sucks hard. Jason cared but he wasn't sure what to do when it doesn't happen on retail games.
Title: Re: White dots on screen
Post by: KRIKzz on May 23, 2014, 01:30 AM
I wonder if RGB modded system still can output normal composite video? Would be interesting to know if dots still visible via regular ppu output. I don't know how rgb mod working, so, i can't say a lot about possible reasons of problem. May be problems with power supply, if voltage regulator inside of nes can not supply enough current for both devices. Or may be problems with timings
Title: Re: White dots on screen
Post by: Kyle on May 23, 2014, 02:11 AM
I have a spare RGB system but the value is approx 350 USD and I'd be scared to ship it to Ukraine.

I hooked it up to my PVM via SCART and get the same thing. So it's also not the component converter.

I will say it's better than PowerPak. On it you pick a game then get garbage. At least on ED you know before you pick a game.
Title: :(
Post by: bozo55 on May 23, 2014, 04:48 AM
Has anyone tried a Genesis Model 1 power supply?  Those pump out 1.2A vs the ~850mA on the NES units.

If it is a power draw issue as others suspect it might be, I wonder if replacing the voltage regulators or main cap in the system for something more robust would help.

I am looking to RGB mod my AV Famicom for S-Video support, but am weary of having this problem myself...
Title: Re: White dots on screen
Post by: Kyle on May 23, 2014, 04:56 AM
My NES was recapped. I may try the Genny power supply if I get the nerve.
Title: Re: White dots on screen
Post by: evil_ash_xero on May 23, 2014, 11:19 AM
That's pretty interesting, about the power supply.

If anyone does get the guts to do that, let us know how it turns out.

At least on ED you know before you pick a game.

Unfortunately, I tend to have a clear menu screen, and then the game starts going wonky in the first stage, after playing it for a while. It's quite aggravating.
Title: Re: White dots on screen
Post by: Kyle on May 23, 2014, 05:02 PM
I'll ask Jason if he thinks the Genesis AC is okay. I would feel like a goober if it's not especially when I've killed electronics using the wrong power supply.
Title: Re: White dots on screen
Post by: evil_ash_xero on May 23, 2014, 05:18 PM
Can you use a Genesis AC, without changing any of the insides of the NES?

Cause I got Genesis ACs all over the place.
Title: Re: White dots on screen
Post by: Kyle on May 23, 2014, 05:44 PM
As long as its a model 1 it is supposed to work fine. I haven't tried yet.
Title: Re: White dots on screen
Post by: KRIKzz on May 23, 2014, 06:03 PM
Another theory: terminate resistors. Seems like octal buffers on NESRGB does not have built-in terminate resistors, external resistors is not present also. I had a problems with ppu during N8 development, when i tried to use buffers without terminate resistors. But i had another kind of problem, mainly it was notable as IRQ problems
Title: Re: White dots on screen
Post by: TeamShake on May 23, 2014, 07:07 PM
You can use a genesis 1 power adapter on a nes but not vice versa.  The model 2 supply would be fine also just the tip doesn't fit in the nes.
Title: Re: White dots on screen
Post by: bozo55 on May 24, 2014, 03:28 PM
The model 2 supply would be fine also just the tip doesn't fit in the nes.

Not only is the Model 2 a different size pin, but it is also centre pin positive...  I don't know if that matters since the original NES takes AC input.  I read that DC Adapters work fine.  I do know that the Gen Modell 1 Adapter works fine in my Super Famicom and AV Famicom.  It outputs around 13V unloaded, which is what my NA SNES adapters output.  The Japanese HVC adapters output around 17V  from a 120V outlet, which I believe is dangerously high. 
Title: Re: White dots on screen
Post by: TeamShake on May 24, 2014, 03:34 PM
you can use a center pos or neg dc supply as long as its around 9 to 10v.  I have seen where some people have used up to 16v supply and said it works though but that would make the voltage regulator run pretty hot.  The NES comes with an ac supply but converts it to 5V DC inside the system.
I use a generic 9v DC center positive supply on my nes.
Title: More bugs being discovered on the NES RGB board.
Post by: bozo55 on May 24, 2014, 11:07 PM
V1.6 firmware has just been released to address a bug that was introduced in V1.5 (graphical glitches in SMB2/SMUSA).

http://shmups.system11.org/viewtopic.php?p=1021564#p1021564

I think I will hold off on this mod until it goes through more validation/testing.
Title: Re: White dots on screen
Post by: evil_ash_xero on May 28, 2014, 11:02 PM
We're up to 1.7 now.

If anyone who is having this problem has the opportunity to test out 1.7 with the N8, that would be most helpful.
Title: Re: White dots on screen
Post by: Kyle on June 11, 2014, 02:47 PM
You should have circled back around!

http://www.youtube.com/watch?v=41HNCD113og
Title: Re: White dots on screen
Post by: evil_ash_xero on June 25, 2014, 09:37 PM
Jason is seeing this problem with other top loaders now.

I do not think this is specific to my system at all.

I'm thinking most people have front loaders, and that is why we aren't hearing about this more.

Maybe it is power consumption.
Title: Re: White dots on screen
Post by: Kyle on June 26, 2014, 02:19 AM
What's fun is I had 4 or 5 toasters and I was going to send him a couple to mod. He said that he strongly recommended the top loaders and sold me them instead. I'm not mad or anything. It's just sucks if this is solely a top loader issue. Maybe he could relocate my mods to toasters.
Title: Re: White dots on screen
Post by: evil_ash_xero on June 26, 2014, 08:57 AM
I'm asking around on shmups forum. And one guy has a top loader that has no problems.

This is mysterious, isn't it?

But it does seem to happening with top loaders, when it does happen. Specifically the 101.
Title: Re: White dots on screen
Post by: MockyLock on June 26, 2014, 11:13 AM
I have myself modded 2 NES "toaster", one PAL and one NTSC.
Both works as expected, with no dot or any glitches in the screen.
I think top loader are recommended because of the insertion system of the cartridge, that seems to be more efficient.
Title: Re: White dots on screen
Post by: adimifus on July 01, 2014, 06:07 AM
I have a top loader/n8/nesrgb and i've never had any issues like this. I am using a Famicom version of the N8. Is there any possibility that would make a difference?
I use a model 1 genesis power adapter, and i removed the 220uF caps ion the NESRGB board itself because the SNES scart cable i use has them in it (I switch it to my snes and n64 to play them). I think those are the only real differences in my setup.
My NESRGB is a first batch board, and hasn't been updated to a newer firmware yet (going to soon-- just got a USB Blaster).
Title: Re: White dots on screen
Post by: MockyLock on July 01, 2014, 09:54 AM
The very first batch had an issue in the background color, remaining grey for most games. For exemple, Super Mario Bros had this problem.
Did you get this ?
Title: Re: White dots on screen
Post by: adimifus on July 01, 2014, 05:13 PM
The very first batch had an issue in the background color, remaining grey for most games. For exemple, Super Mario Bros had this problem.
Did you get this ?

Wasn't that the second batch, with the different RAM chip? In any case, the only issue i have with mine is the messed up colors in Orb 3D and Duck Maze. (That i know of)
Super Mario Bros. looks and plays fine. I've never noticed any issues with colors being off in any other games I tried.
Title: Re: White dots on screen
Post by: Kyle on July 01, 2014, 05:42 PM
Second batch pre-firmware upgrade.
Title: Re: White dots on screen
Post by: Arnold101 on July 02, 2014, 08:33 PM
I have RGB original famicom and i have red dots with everdrive only. Is this problem fixed or Not? No problem with original carts
Title: Re: White dots on screen
Post by: evil_ash_xero on July 04, 2014, 12:19 AM
Not fixed yet. But it seems like a lot more info is getting compiled.

When I first mentioned it, I thought I was the only guy with the problem. Very frustrating.
Title: Re: White dots on screen
Post by: KRIKzz on July 04, 2014, 03:23 PM
Is this problem fixed or Not? No problem with original carts

EverDrive N8 - no problems with original PPU. I think that RGB board should be fixed to support flashcarts, not visa versa
Title: Re: White dots on screen
Post by: evil_ash_xero on July 04, 2014, 11:34 PM
I agree.
Title: Re: White dots on screen
Post by: Arnold101 on July 08, 2014, 12:59 PM
OK thanks krikkz
Title: Re: White dots on screen
Post by: bozo55 on July 23, 2014, 02:17 AM
http://www.youtube.com/watch?v=lzbHbUAjdxI&index=1&list=UUyUGc-ZrN4JSox9Kbvnxeug

I think this problem has been resolved finally.  It has to do with the RF transistor causing interference.  Removing the transistor from the NES board seems to be the fix.
Title: Re: White dots on screen
Post by: Kyle on July 23, 2014, 04:08 AM
Confirmed. I had two systems from Jason and this fixed both.

(http://srktt.com/photos/nestrans.jpg)
Title: Re: White dots on screen
Post by: Paulweeze on July 23, 2014, 04:18 AM
Sell me your Homer Kyle! My bro is nuts for legos lol. Wow, all of this time it was a rf transistor. Glad to hear that you guys found a fix, gives me the greenlight to mod my system when i get a N8.
Title: Re: White dots on screen
Post by: evil_ash_xero on July 30, 2014, 02:01 PM
Yeah, that's my system in the vid...and I have yet to have any snow show up yet.

So, I'm quite happy about that, obviously.

Seems that it's a real fix.