NESRGB board available now

[Voultar]

I don't have a Capture Device, so I'm only able to see what's outputting to my 47'' LED Television.

Using CS, I'm not seeing any of that diagonal "clock" interference. But I'm also using an XRGB-Mini, it could be filtering it out.

Actually, it is filtering it out, I just ran S-Video out through the XRGB-Mini and the diagonal interference no longer seems to appear. Directly connected to any of my televisions, however, it's awful to look at.

[Pasky]

X-RGB mini filters out a lot, it can filter out the genesis's native jailbars on a model 1.

[CkRtech]

Actually, it is filtering it out, I just ran S-Video out through the XRGB-Mini and the diagonal interference no longer seems to appear. Directly connected to any of my televisions, however, it's awful to look at.

Hey what settings are you using on the XRGB-Mini? I have used all of the different sync spots on NESRGB, and I have never eliminated all of the interference. I would *prefer* to just eliminate it from the NESRGB, but I don't mind compensating with the XRGB just to maintain my sanity since I have yet to completely eliminate interference (mostly in solid colors) from the NESRGB itself.

[Voultar]

I've not tweaked or changed anything. It just came in the mail last Thursday, and I haven't really had an opportunity to dive into all of the settings yet. Its quite remarkable that its filtering out that diagonal interference.

The Model 1 Genesis jail bars however are just a clear as they were before (via SVideo)

I can take pictures if you're interested in seeing.

[ms06fz]

I've noticed that diagonal interference in my AV famicom vs my US top loader. On my top loader I can't see it at all. But on my Revision 1 AV famicom, it's there, clear as day through RGB and S-video.

This strikes me as a potentially interesting test case. Maybe it can teach us something about the problem.

I'm assuming this is two separate NESRGB boards, one per console. I'm wondering, if you switched which console each board was in, would the AV Fami still be the one with problems, or would it switch to the NES?

How are your connections set up in the US top loader? Did you remove the RF modulator? Did you put in a multi-out connector? And what about the AV Fami? Is the PPU composite signal going out over the multi-out connector, or did you cut that trace and put the NESRGB composite signal there?

The NESRGB uses the composite video from the PPU for a couple different purposes - generating a sync signal and getting one of the palette index bits - but the board also feeds the PPU video out through the same path that it follows in an unmodified console. I'm wondering if it's maybe picking up some interference along this path and carrying it back to the NESRGB. Or maybe it's some kind of signal reflection thing, since the composite video is now following two different paths. Maybe another thing to try would be to sever the connection between PPU pin 21 and the main board.

[CkRtech]

I feel bad that you guys are having these problems, but I am also glad it is not just me. I've stuck my eyeballs on my TV to try to see the lines during a graphic-intensive screen and can't see interference. Then I get solid colors and see diagonal lines in them. (Most recent was TMNT intro and then quite a bit in the underwater bomb disabling stage due to all of the blue.) hmm. I just got an elgato game capture. I suppose I could capture it for example.

Although I think we have quite a few examples...we just need a miracle solution.

I know some of you guys have a scope...but I don't know if you're the ones with the issues. Calling all scopers! We need some diagnostic assistance.

[Pasky]

I'm assuming this is two separate NESRGB boards, one per console. I'm wondering, if you switched which console each board was in, would the AV Fami still be the one with problems, or would it switch to the NES?

Yes, the one that is in the US top loader is a 1st batch nesrgb, the av famicom is the latest batch.

How are your connections set up in the US top loader? Did you remove the RF modulator? Did you put in a multi-out connector? And what about the AV Fami? Is the PPU composite signal going out over the multi-out connector, or did you cut that trace and put the NESRGB composite signal there?

Yes, the RF modulator is removed and put a RCA jack for audio in it's place on the US top loader.


My suspicions are the design changes on the AV famicom PCB. It has a much smaller ground plane, which may be causing ground bounce.

[Voultar]

I troublshooted as far back as I could. I swapped encoders, traced the lines back for interference, and even pulled Y/C off of the encoder and built the S-video circuit on breadboard, no change.

The interference is being fed into the encoder, I believe this issue is originating from the colorburst/subcarrier generator.

[ms06fz]

Yes, the one that is in the US top loader is a 1st batch nesrgb, the av famicom is the latest batch.

Would you be up for swapping the two boards? I understand it can be a fairly demanding process...

I troublshooted as far back as I could. I swapped encoders, traced the lines back for interference, and even pulled Y/C off of the encoder and built the S-video circuit on breadboard, no change.

I haven't investigated this issue myself yet, (not that I know a whole lot about this stuff) so I'm just kind of grasping at straws here - but I am taking your discoveries into account here. The interference is apparently present to some degree in the RGB signal, and then encoding it to S-Video makes it worse.

I'm trying to account for possible sources of this interference, and it seems to me that the PPU's composite signal is a strong possibility. Either something in the signal itself, or something in the other connections made to the signal, carrying interference from elsewhere in the NES back to the NESRGB. If the interference is coming from the NES itself via the PPU composite, then the interference may either be getting through the sync stripper, or jumping over to another line via crosstalk.

The simplest way to eliminate interference from the NES via the composite line as a possibility would be to cut that connection. If it turns out my build has the interference (I've only used it on my Commodore 1701 so far - I may need to try it on my LCD TV if I want to see if the interference is there) then I will probably give this a try.

[Pasky]

Maybe when I have time.

You can sever Pin 21's connection without damaging the NESRGB or the NES pcb by removing the transistor inline with the circuitry from the NES board (Q1?). IIRC (at work can't check) that's the first thing the composite output runs to.

[ms06fz]

Alternately (and I think this would be my preferred solution, to eliminate any possibility of picking up EMI anywhere between PPU pin 21 and the first component it's connected to on the motherboard) - separate pin21 from the rest of the pin header and remove it from the NESRGB. It should be pretty simple to replace the pin later if desired.

[ms06fz]

Didn't someone make a switchless palette-mod already?

If so, has he/she made the code publicly available, or perhaps even sells the ICs. That would be better as I don't have a PIC programmer

I have a customer who would really like a switchless install, so any help would be greatly appreciated.

Indeed, I'd seen the switchless mod, but I forgot about it completely... Pretty neat idea, though it didn't take into account things like Zelda's "hold down the reset button when you turn the power off" (though you could still do it, if you got the timing right.)

Anyway, my palette selector isn't "switchless", I just wanted a very small switch without any visible hardware on the outside of the case holding it on. I ultimately went with a little tactile pushbutton, (kind of like this one) poking out through a 3.5mm hole next to the original A/V jacks on the side of the machine, and epoxied to the inside of the case. So it pretty much just looks like a 3mm black dot on the surface.

Since mine is built on Arduino rather than PIC, you can write the code to the board without any "special" hardware (Normally you can load code onto an Arduino through its bootloader. Since I needed to get rid of the bootloader's startup delay, I used a second Arduino as an AVR programmer using the "Arduino ISP" sketch.) The code could surely be adapted to other AVR micros as well: The Arduino Pro Mini I used normally sells for $10, but the same job could be done for a couple bucks by using (for instance) an ATTiny85 with no external components. But mounting the Pro Mini to the NESRGB was very convenient: the two boards are connected together with a 4-pin header, plus an additional wire for positive voltage.

I'll post my code when it's ready, so if you or anyone else is interested in using it they're welcome to do whatever they like with it.

It would take a little bit of work to adapt the code for a "switchless mod" though: in the switchless mod a short press on the reset button generates a system reset once the button is released, while a longer press (half second, I think) cycles through the palette options. In my code short presses cycle through the NESRGB palettes (when the button is first pressed, not when it's released) and a long press turns NESRGB on/off. (I didn't want that feature to be part of the normal cycle, since it screws up video output until the NES software rewrites the palette.) So the behavior isn't quite the same, but it's C++ code so it's a little easier to work with than assembly...

[Sparky]

Didn't someone make a switchless palette-mod already?

If so, has he/she made the code publicly available, or perhaps even sells the ICs. That would be better as I don't have a PIC programmer

I have a customer who would really like a switchless install, so any help would be greatly appreciated.

Here is some information provided by forum member yxkalle:

yxkalle switchless modification information NEWER

yxkalle switchless modification information OLDER

[Skips]

Just a quick post to show how I do the install in an AV Famicom since I have a lot of people asking. I am pretty big on being able to remove the kit easily in case I need to test it in another system so I went for a an install that would allow just that. No palette switch on this one just because I am too lazy to install it on my personal unit (and hardly ever change it anyway). The power LED uses the 5v and ground pins on the kit itself which makes it easy to open and work on the system (nothing is physically attached to the shell). I will install a pin header for the JTAG as well once the programmer comes in. I also started using 14 pin connector housings so it would look a bit cleaner.

P.S. The crappy cap is only there until my programmer gets here later this week.

[kamiboy]

Yesterday the postman knocked on the auld door with a box containing my board in hand. Today I managed to arse myself into spilling the innards of my AV Famicom and shove the board in there. Took 2-3 hours total and worked like a charm.

Cannot say that I am noticing too much of a difference compared to my Titler, but I sure can see a difference in the amount of space the Titler takes compared to the tiny AV Famicom. So back in the box the Titler goes for retirement. Cheerio old gal, you served me well.

Cheers Tim, you are a god among men, or a bunch of overgrown babies at the very least.

[leonk]

Yesterday the postman knocked on the auld door with a box containing my board in hand. Today I managed to arse myself into spilling the innards of my AV Famicom and shove the board in there. Took 2-3 hours total and worked like a charm.

Cannot say that I am noticing too much of a difference compared to my Titler, but I sure can see a difference in the amount of space the Titler takes compare to the tiny AV Famicom. So back in the box the Titler goes for retirement. Cheerio old gal, you served me well.

Cheers Tim, you are a god among men, or a bunch of overgrown babies at the very least.

Is the Titler RGB? and if so, does it use the same pallette as NES/Famicom or more like PC10?

[ApolloBoy]

Is the Titler RGB? and if so, does it use the same pallette as NES/Famicom or more like PC10?

It only has S-video and composite but it can be easily modded for RGB. Obviously since the Titler has an RGB PPU it has that funky color palette and compatibility issues with certain games.

[ms06fz]

Finally tested my modded NES on my LCD TV. Among other things I was looking for the interference other people have reported on some installs.

All I found on this one was a very small amount of jagged edges on rectangles (present also in the PPU composite) and a little bit of noise in large fields of a single color - like a travelling flicker. I doubt I would be able to catch it on camera. I may still try disconnecting pin 21 to see if it makes any visible difference in the S-video signal, but mostly I'm quite happy to now have this build finally closed up.

I'm also happy to see that this resolved the "checkerboard echoes" I saw in certain games on that TV (a bug in the TV's upscaler? Or just a bad interaction with the NES?) I expected it would, but didn't know for sure until I tried it...

After all I went through to make my pushbutton selector for the palette, I'm feeling like I won't even put a palette switch on the next build. I just haven't seen any situations where I actually want to use the other palettes. Even the "standard" palette seems pretty bright. Also, I think when using a pushbutton to control the palette selection, you really need some kind of audible or visible indicator of what state you're in, and when you change states... I need it to beep or something, especically when I do the "long press" to turn the NESRGB off - 'cause if you switch from PPU video to turn NESRGB back on, the picture doesn't change until the game rewrites the palette... So I hold down the button and it just looks like nothing changed. The "Switchless" mod has this via blinking the power LED, I think.

Now that I got my NES install pretty much wrapped, I can start on the AV Famicom...

[CkRtech]

All I found on this one was a very small amount of jagged edges on rectangles (present also in the PPU composite) and a little bit of noise in large fields of a single color - like a travelling flicker. I doubt I would be able to catch it on camera. I may still try disconnecting pin 21 to see if it makes any visible difference in the S-video signal, but mostly I'm quite happy to now have this build finally closed up.

Solid colors are definitely where my woes come from in the form of rolling diagonal lines.

Thanks for reporting in, ms06fz. I have been keeping my eye on the thread for any additional info along these.....lines.

[ms06fz]

All I found on this one was a very small amount of jagged edges on rectangles (present also in the PPU composite) and a little bit of noise in large fields of a single color - like a travelling flicker. I doubt I would be able to catch it on camera.

Solid colors are definitely where my woes come from in the form of rolling diagonal lines.

I think I could be seeing a faint or fast-moving version of that, or maybe I'm seeing exactly that and my TV's scaler is garbling it so it just looks like a bit of faint noise. Not really sure, and unfortunately my LCD TV is the only display I've got good enough to display these kinds of artifacts. Were there any particular colors or games that made the artifacts especially visible?

[CkRtech]

I think I could be seeing a faint or fast-moving version of that, or maybe I'm seeing exactly that and my TV's scaler is garbling it so it just looks like a bit of faint noise. Not really sure, and unfortunately my LCD TV is the only display I've got good enough to display these kinds of artifacts. Were there any particular colors or games that made the artifacts especially visible?

The most recent one that jumped out at me was the opening to Teenage Mutant Ninja Turtles. There was quite a bit of noise in the green backgrounds as the game introduced each one of the characters.

Edit: The pause menu's blue behind Splinter/April also looks quite noisy.

[leonk]

Let's put this into perspective. How noisy compared to say a top loader nes that shows jail bars? I think there's only so much the nes can do when it comes to color and video. A lot of video noise starts in the CPU and were not even touching it with this mod.

The NESRGB might not be perfect for the most critical eyes that pixel peep the entire frame but it's light years ahead of any other solution. I personally will never play any nes that doesn't have an NESRGB installed in rgb mode.

[CkRtech]

Well if you think the CPU might be causing noise somehow, I am all ears. Meanwhile, I want to encourage those that are diagnosing these issues. In my opinion, the noise is quite obvious in solid colors. It could be a very simple fix. We just need to find it.

[ms06fz]

Let's put this into perspective. How noisy compared to say a top loader nes that shows jail bars? I think there's only so much the nes can do when it comes to color and video. A lot of video noise starts in the CPU and were not even touching it with this mod.

The severity of this particular issue seems to vary between different installs. On mine, it's very, very faint, but I have managed to (finally) spot it. I believe it's probably present to some extent on all installs.

I'm totally with you, I think the quality of NESRGB is fabulous. There are little artifacts and such, but otherwise the picture quality is great. But if this issue is a more significant problem for some people, maybe I can help find a solution.

I still suspect that the interference may be coming in via pin21's (composite out) connection to the motherboard. It seems like an obvious possibility anyway. It runs through the heart of the NES and also connects (through filters) to the PLD and to the video encoder. I'm planning to disconnect my pin 21 from my first build tomorrow, see if that has any influence on the (faint) interference I'm seeing on my build.

Incidentally, is it just me or does the "native" palette seem awfully bright? Part of me wants to try to tweak the palette, darken up a few of the colors...

[CkRtech]

So I captured some footage using a elgato game capture HD, and TMNT's issues in the recorded video manifest as a shimmering like effect in the solid colors rather than rolling diagonal lines like they do on my plasma display. I could upload it somewhere later if needed.

Results:
NESRGB->xrgb->plasma = rolling diagonal lines in solid colors. Very obvious.
NESRGB->xrgb->game capture HD = shimmering
NESRGB->xrgb->LED monitor = shimmering, but then I changed the picture mode on the monitor and saw the diagonal lines in addition to the shimmering.

I suspect the game capture HD was possibly adding a bit of extra filtering of some sort, but the bottom line is that problem still exists - it just manifests in a different way. I've already made adjustments to filtering on the xrgb mini, and it seems like the xrgb is currently "doing its best" to filter it out.

Look forward to your results with my fingers crossed, ms06fz.

[Einzelherz]

Out of curiosity, is there a catalog somewhere of the different NES board revisions? All of the issues I keep seeing crop up in here, to me anyway, seem like perfectly normal variances in parent hardware.

[ms06fz]

"Shimmering" is a good description of what I've been seeing. The diagonal lines are there but barely visible, but there's a blotchy, flickering interference in certain large areas of color. Both effects become more apparent when using the Playchoice palette, and (it seems) less apparent when using the emulator palette. I wasn't able to spot the issue in TMNT I think, but I did see a bit of it in Rockman 3 (on the "boss introduction" screens mainly) and it was pretty easy to spot in Punch Out (in the first few bouts, over half the screen is filled with a blue that hits this issue)

(EDIT): OK, actually tried Punch Out again and the "shimmering" effect was worst in the standard palette and not so bad in the other two.

[Fudoh]

In my opinion, the noise is quite obvious in solid colors.

but the XRGB Mini is extremely sensitive to noise. The noise would likely not show up most other setups, no matter if running through a video processor or with a plain connection. If it's really a problem and you can't get rid of the noise by adjusting the A/D level on the Mini as well as switching to a processing mode with a higher LPF setting (upper row, standard for example), you might have to look into the possibility of building a better LPF for your NES or FC.

[Bancho]

Well my board showed up in 6 days from Aus>UK so that was pretty impressive.

I'm just waiting for my AV Famicom to turn up after selling my PAL toaster.

I'm ok at soldering but not really done any de-soldering before, so ! decided to have a practice on a Pilotwings board I had spare which I removed the DSP chip using the stove method which worked brilliantly actually but I don't fancy waiving a famicom board over a stove lol. I used one of those cheap Maplin £16 de-soldering iron/pump combos. Worked for most of the pins but there were one or two stubborn pins. I learnt a lot doing this and will be using some wick on the top side to remove some of the solder before attacking the bottom. It looked like one of the pin holes was slightly damaged on my practice but that was one of the stubborn pins and probably used to much heat trying to suck out the solder.

Took me about 45 mins to get the chip out. Don't think I did to bad for my first attempt. It's most definitely worth practising on something before working on the precious famicom board!



Excited now to get the board in and enjoy the RGB quality on my trinitron

[Voultar]

You need to add fresh solder to those pins to promote adequate wetting before desoldering.

You've lifted a couple of via's, judging by your picture above.