NESRGB board available now

[LaC]

Hi everyone,

I recently switched from a Sony PVM-1954Q to a PVM-2030 and am now experiencing sync issues, but only with my NES RGB setup. I did the NESRGB mod myself back in 2014 and I believe I have one of the original revisions of the board. I’ve been using a SNES SCART cable made by Retro Console Accessories. The issue I’m encountering is that the screen goes black randomly every now and then. Has anyone else experienced similar issues with this setup or have any advice on what might be causing this and how to fix it?

Tim released a firmware 1.9 for the original boards that fixes jitter on the sync line. You loose the palette switch though.

This fixed the sync issue for me with the OSSC.

https://www.etim.net.au/nesrgb/background_fault/

Interesting. It appears to be addressing something else, but I guess won't hurt to try to update it.
Thanks.

[nawendt]

Hello,

For Christmas my wife bought me a NESRGB board, and I installed it semi successfully. It seems to have something like the "clock hardware bug" I found on V4 errata page.

My NES is a PAL FRA, with the CPU, PPU, and Crystal from a Famicom so it runs on 60Hz.

I already fixed the palette not setting bug (removing pin 22, 1k between 22 and 40, as per viewtopic.php?f=6&t=70734&p=1511761#p1511761 )
And added a 47pF (did not have more on hand) between 13 and 20

But I really don't know where to go for the "corrupted sprites", maybe you can help me ?

You'll find 3 exemple pictures bellow

Thanks for your help

I just installed an NESRGB 4.1 (rev 23.19) into a top-loader and saw similar issues to this (see attached examples from Kriby and SMB3). When this would occur, it would manifest as pixels looking off on the right side of lots of sprites. What was interesting about this issue was that it was intermittent. You could power cycle and eventually get sprites that would all look correct. If you would boot up to a good state, you could play on and it would not crop up later. Boot up to the pixel-shifted state, and that is what it would be like as you continued playing. Sure seems like some sort of sync issue, but I do not know where to look in terms of troubleshooting it. Having looked at Tim's known issues and forum posts, the clock bug is a possible candidate in terms of the culprit. Again, I am not sure enough and did not want to go poking around in an otherwise perfectly fine install before having more confidence in the root problem. I did email Tim but he has not responded after being on break. Any help on this would be appreciated.

[ShinDigPig]

Hello, I've recently done two NESRGB installations into AV Famicoms. The 2nd one I did had no issues, and both are the same configuration.

The first one seems to have trouble loading colors correctly. But, it also goes away after a power off / power on after a minute. A press of the reset button doesn't fix it. Here are a few captures from before and after a power cycle. It's happened once after a few hours of play, but only once that I can recall. It happens on a cold start every time.

Before Power Cycle
https://ibb.co/3C65myD
https://ibb.co/GkNQxLb
https://ibb.co/HpxLbdS
After Power Cycle
https://ibb.co/2ytJZWH
https://ibb.co/Ss7PNnG

I've changed the capacitors & tried the capacitor between 13 and 20 (and removed when there was no change). I've also removed the NESRGB and replaced the PPU, and it was functional afterward. I also get significantly more screen jitter on this one vs the 2nd, and it seems to go away as it warms up. Or improve at least. Here's a picture of the Famicom if there's anything wrong you could spot there. I could try swapping the NESRGB boards between the units and seeing if it follows the system or NESRGB board, but haven't done that yet. I just have #2 set up and #1 as a backup.

Famicom
https://ibb.co/ts6mF31

[apoido]

Hi.
I have NESRGB v4.
Can I set it to any palette by rewriting the firmware ?
(RC2C03B palettes ,RP2C04-0001 palettes ,etc..) .

It would be great if it could support switching palettes in VS system.

Thanks.

[bobrocks95]

*snip*

*snip*

*snip*

I have very similar issues to all 3 of you now that I've put some time in on my NESRGB system. On boot things are either good, or all colors are offset to the right with some weird lines or sprite corruption occasionally.

https://photos.app.goo.gl/Tk333jAYSvgaHuM59

Two of the pictures show the Castlequest title screen (just some purple font on a black background) on a good boot and on a bad boot. I also replaced the startup capacitor like the guide says.

Was there another potential fix for this? I mean for right now, easy enough to just restart the console when it's happening.

[bobrocks95]

On the 4.0 errata page, are the listed bugs ONLY for V1 4.0 hardware? It really sounds like I have the clock bug at the bottom, since I've also noticed left/right shifting when on a bad boot with color issues:

Symptom: Noise on the clock line can cause the NESRGB board to become unsynchronised with the PPU. This looks like colour fringes on the edge of objects and the picture moving left/right by one pixel.

I bought my hardware late 2023- wonder if it's V1 only, if Tim's US distributor still had unupdated V1 hardware lying around which would suck.

[viletim]

The flickering pixels in sprites that occurs on some power cycles is due to a firmware bug.

You can read about it here. NESRGB > Buggy Releases > 2023 Flickering dots in sprites on some power cycles. There is a modification to fix it detailed as well.

This actually a flaw in the data PPU sync logic that has been there since the very beginning. I only recently found out that PAL and NTSC PPUs are are outputting data on different clock edges relative to the master clock. When I first designed the NESRGB I used NTSC hardware, with PAL support added on. The same goes for when I re-wrote it for the new hardware of version 4. When I did the big bugfix firmware version 2 for version 4 hardware, I was testing on PAL hardware. I inadvertently optimized the PPU sync logic for PAL, and made NTSC performance marginal. It was only once I'd received some complaints about it that I investigated and found they need to be handled differently.

It's fixed in the currently firmware, but the older ones that show symptoms can still be saved by adding some caps to the EXT signals that will change the timing very slightly, enough so the PPU sync logic works correctly. Most NESRGB boards do work fine, it's just a few that run into this bug.

[bobrocks95]

The flickering pixels in sprites that occurs on some power cycles is due to a firmware bug.

You can read about it here. NESRGB > Buggy Releases > 2023 Flickering dots in sprites on some power cycles. There is a modification to fix it detailed as well.

This actually a flaw in the data PPU sync logic that has been there since the very beginning. I only recently found out that PAL and NTSC PPUs are are outputting data on different clock edges relative to the master clock. When I first designed the NESRGB I used NTSC hardware, with PAL support added on. The same goes for when I re-wrote it for the new hardware of version 4. When I did the big bugfix firmware version 2 for version 4 hardware, I was testing on PAL hardware. I inadvertently optimized the PPU sync logic for PAL, and made NTSC performance marginal. It was only once I'd received some complaints about it that I investigated and found they need to be handled differently.

It's fixed in the currently firmware, but the older ones that show symptoms can still be saved by adding some caps to the EXT signals that will change the timing very slightly, enough so the PPU sync logic works correctly. Most NESRGB boards do work fine, it's just a few that run into this bug.

Thanks Tim, that does sound like it- sprite edges colored incorrectly, determined once at power-up and sometimes working fine.

So I forget, is it not possible to update the FPGA firmware on the version 4 board? I don't see any software packages listed online so it looks that way...

[Odyssey113]

I need help with install. Color pallet not looking correct after install. the board is a v4 23.03. I am using valtairs qsb ffc kit. IGR and pallet switching working. i have since removed IGR and pallet select, just to make sure that wasn't an issue. I removed and soldering a different multi-out connecter, Checked and rechecked all jumper settings. tried the aux voltage regulator. re capped the whole NES. rechecked and re-soldered all joints multiple time. i even tried another ppu from another working console to no avail. The PPU came off a working NES and I got the same results. It appears that I am missing EXT2 line. verified by grounding Jumper D to ground. verified all connections with a multimeter. even the EXT2 under the PPU. I have a little scope i used to probe the EXT lines im getting the same "signal" wave length from the PPU and the level translator IC and at the FPGA chip. Its a little DSO Nano scope, i may not be using it properly. Is there anything im missing or maybe over looked. I have since ordered another rgb board and soldered that kit with one of the working PPU's on the same NES board and it work as expected. Ive been beating my head against the wall trying to figure this thing out. Any help would be greatly appreciated.
https://imgur.com/a/Sbgdul3
pictures of problem and install and scope

Looks like you had the same problem that I did. My color symptoms and error LEDs were just like yours. Looking at your pics, it looks like you have the same faulty chip that I did from what I could see. You should email Tim with your order number and 'help' in the headline and tell him what's happening. He sent me out a replacement RGB kit free of charge.

Tim emailed me back and confirmed that I do have bad chips on my RGB board. If anyone is experiencing similar issues on one of their error LED lights, namely the EXT LEDs, check to see if you have this chip on your board. If you have this particular chip, it's faulty.

Looks like this is the board I ended up getting as well, from my testing results. Led 2,4,6, and 7 not showing on SMB3 load screen when shorting pad D, and picture looks exactly like this. I emailed Tim, hopefully I can get a board not plagued by this.

[MaRCer]

Hi guys.
Nesrgb 41 with V5 firmware - one point on the Lattice.
Installed on AV Famicom, J1,J3,J5 are closed. I soldered all the wires, the palettes from the gamepad switch, the reset from the gamepad works, the picture shows both composite and RGB. But there are problems with the picture - everything is fine with the background colors, and the sprites seem to use not their palette, but the background palette. Only the LED of the selected palette is lit during operation. I removed NESRGB, everything is fine without it. On the NESRGB itself, all contacts are called from the connector to the pins on the board. There are no short circuits either.


It turned out that the 7805 produces only 4.5 volts. On the other famicom, the board is working fine. I will deal with the power supply, NESRGB has nothing to do with it.

[Odyssey113]

Hello,

For Christmas my wife bought me a NESRGB board, and I installed it semi successfully. It seems to have something like the "clock hardware bug" I found on V4 errata page.

My NES is a PAL FRA, with the CPU, PPU, and Crystal from a Famicom so it runs on 60Hz.

I already fixed the palette not setting bug (removing pin 22, 1k between 22 and 40, as per viewtopic.php?f=6&t=70734&p=1511761#p1511761 )
And added a 47pF (did not have more on hand) between 13 and 20

But I really don't know where to go for the "corrupted sprites", maybe you can help me ?

You'll find 3 exemple pictures bellow

Thanks for your help

I just installed an NESRGB 4.1 (rev 23.19) into a top-loader and saw similar issues to this (see attached examples from Kriby and SMB3). When this would occur, it would manifest as pixels looking off on the right side of lots of sprites. What was interesting about this issue was that it was intermittent. You could power cycle and eventually get sprites that would all look correct. If you would boot up to a good state, you could play on and it would not crop up later. Boot up to the pixel-shifted state, and that is what it would be like as you continued playing. Sure seems like some sort of sync issue, but I do not know where to look in terms of troubleshooting it. Having looked at Tim's known issues and forum posts, the clock bug is a possible candidate in terms of the culprit. Again, I am not sure enough and did not want to go poking around in an otherwise perfectly fine install before having more confidence in the root problem. I did email Tim but he has not responded after being on break. Any help on this would be appreciated.

We're you ever able to fix this on your install? with any of the posted fixes? I'm having the same issue with mainly those two games you mentioned. Others too though like Castlevania 3

[RocketKnight]

My NESRGB-modded console suddenly started lacking red video. Did anyone else experience that problem and find out its cause?

[cyberops]

hello, ive got a top loader with nesrgb V4.1 23.03 that freezes when a dialog shows from top to bottom of the screen with Final Fantasy NES cart with 72p to 60p converter. does someone has idea why this happens?

https://photos.onedrive.com/share/9CFF4 ... o&e=I3onyO

[kitty666cats]

Have there been a lot of recent NESRGB issues as of late (detailed on other forums, etc)? Or is a decent handful of people popping in here every few months the norm? From my outsider’s (never rocked a RGB modded or RGB-capable console improved with a video amp PCB) view looking in, it kinda looks like people having issues has become more prevalent lately…?

[Odyssey113]

Have there been a lot of recent NESRGB issues as of late (detailed on other forums, etc)? Or is a decent handful of people popping in here every few months the norm? From my outsider’s (never rocked a RGB modded or RGB-capable console improved with a video amp PCB) view looking in, it kinda looks like people having issues has become more prevalent lately…?

Version 4 seems to be plagued by several different issues. Part of it is certainly that there is no reasonable support system in place for any of us. Getting an answer from Tim directly seems to be very hit or miss (miss so far for me) and just in general nobody appears to know fuck about shit when it comes to fixing any of these issues so you're left to the forums and just hoping that someone comes along with a viable answer.

My situation is quite frustrating because I've now technically got a successfully installed product but it drops out colors randomly on many games that Id like to play, I've tried all the fixes I could find online with adding little 100pf-220pf caps in specific spots, and while it's helped a little, it still happens very frequently.

I just want a working product. It's very disappointing. Especially since when it works like it should, it looks great.

[TooBeaucoup]

Have there been a lot of recent NESRGB issues as of late (detailed on other forums, etc)? Or is a decent handful of people popping in here every few months the norm? From my outsider’s (never rocked a RGB modded or RGB-capable console improved with a video amp PCB) view looking in, it kinda looks like people having issues has become more prevalent lately…?

I'd say there's been more issues on this latest revision than there ever was on the others. That said, the last time I talked to Tim, he had shipped a few hundred of these latest kits, and if you consider there's only been a handful of people with issues on this forum and a couple others, I wouldn't call the latest issues widespread or anything. The problem is more like Odyssey pointed out, as in there's no good official way to get support other than emailing Tim with your order number and hoping he has time to see it.

However, if you go way back to the original kits, there were certainly people who had issues as well. The biggest thing with the NES RGB kits always seemed to be that it behaved better on some motherboard revisions versus others. You might have two dozen people have hassle-free installs, and then someone else with a different motherboard not have as smooth of a time.

[Odyssey113]

Tim got back to me and confirmed those chips (SN74LC541A) are defective and he's getting me a replacement sent.

Thank you Tim, and sorry I bitched so much! (I'm midlife crisis-ing a lot lately) You're the man!

[TooBeaucoup]

Tim got back to me and confirmed those chips (SN74LC541A) are defective and he's getting me a replacement sent.

Thank you Tim, and sorry I bitched so much! (I'm midlife crisis-ing a lot lately) You're the man!

He's a stand-up dude. He's usually just got so much stuff going on and so many people sending messages to him that I imagine it's hard for him to get through them all quickly.

[Ppuman]

FIXED- Reached out to Tim and he helped me trouble shoot. When using the original red and yellow composite outputs and you have the nesrgb board disabled, if you see color issues https://ibb.co/5FGBjtW then open J10 which is the dejitter feature off.
Tim figured this out. He's been very helpful with all my questions and fixed my issue.

Hey Guys,
Just installed my model nesrgb42.
Having weird color tint issues with the very top of my CRT screen. No color issues before installing the nesrgb. Using the existing composite nes connections (waiting on multiout)
Turned the nesrgb off with the controller input start+ select+ hold left 2 seconds.

I want to retain the existing composite port functionality if possible. Will test out the multiout port once it arrives in a few weeks and leave an update here for anyone with a similar issue.

In super Mario bros, the top few inches of blue background area on my CRT is reddish pink.
In super Mario bros 3, the opening screen red curtains, top few inches of screen is yellowish.
In Dr Mario the blue checkered background is pinkish for the top few inches of screen.

I tried ever drive and authentic cartridge with super Mario bros 3, same issue.
Sounds similar to the color tint bug here https://etim.net.au/nesrgb/background_fault/nesrgb40/

The picture below shows the top few inches of blue background in Dr Mario appearing pinkish. (Hard to capture sorry for poor quality image)

Super Mario bros (pink background tint, top of CRT screen) https://ibb.co/5FGBjtW
Dr Mario pic https://ibb.co/mbfvwrk
Board setup https://ibb.co/C119PVM

Thanks in advance for any suggestions on how to fix this.

[Marmotta]

I have an NESRGB ordered from Tim in January this year that has a solid lit LED 7. I know the notes for the v4 boards state that a blinking LED indicates an error with the power up reset circuit, but also that it wasn't really something that showed up with Famicom AVs (which I'm using) and doesn't mention being solid. A quick test seems to show it's working OK, but thought it might indicate something at fault with the NESRGB or Famicom itself?