Introducing the NESessity NES front loader PCB replacement

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low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

friedskater wrote:So I took out the NESRGB and ran the NESessity with just composite video - and got the same result. Official carts work fine, N8 Pro has corruption on the menu. Note that ROMs work fine from the Everdrive. It's only the menu. The same N8 works fine in a PAL frontloader.


I'm also thinking about swapping out the 74LS latches for the 74HC versions.
I recently got an Everdrive N8 pro and am also noticing some glitches with the text on the menu, although mine are not nearly that noticable. The games themselves play fine. I didn't have this issue with the Powerpak, so I'm not quite sure what's going on.

74HC versions can be used to replace the 74LS373 and 74LS139. I have tried both and have not noticed any difference in games, so I just decided on the 74LS versions since that's what the original NES uses. I have digikey part #s in the BOM for both on the tindie.com listing. It also has the part # for a good heatsink to use with a 7805 regulator.

Using a switching regulator is good for low power consumption and cool operation, while using a linear regulator has less ripple on the 5v power for slightly better picture.

I have the v1.2 NESessity boards and am currently testing.

The new PCB has the following changes:
Clock circuit now based off NES top loader
Room for larger heatsink with mounting holes
Potentiometer footprints revised to fit a larger variety of potentiometers

I've also teste a few different composite video amp circuits, but it's looking like the one I was using on v1.1 is still the best.
Last edited by low_budget on Sat Oct 31, 2020 2:55 am, edited 1 time in total.
friedskater
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by friedskater »

low_budget wrote:I recently got an Everdrive N8 pro and am also noticing some glitches with the text on the menu, although mine are not as severe. The games themselves play fine. I didn't have this issue with the Powerpak, so I'm not quite sure what's going on.
Thanks for the info, man. I posted about this on the Everdrive forums, and got the following response from KRIKzz:
Likely ppu bus instability or hold/setup timings little off. Some early ppu revision work worse in pair with rgb mods than other. Menu uses advanced technique for rendering, similar to one used in MMC5. Watch intro in Uchuu Keibitai SDF, may be you will se some other glitches.
I tried Uchuu Keibitai SDF and it is indeed very much messed up, I also tried Castlevania III (as another MMC5 game) and it has corrupted graphics too. I have tried two different PPUs (one from a HVC-CPU-GPM-02 Famicom and the other salvaged from a Twin Famicom), and I've tried it with the NESRGB removed. Again, all have the same results.

I've ordered an alternative heatsink - since I'm in the UK I can't find the suggested part with reasonable shipping, but the alternative should be suitable for at least a test.

So my plan is (in order) - change the regulator, review my solder joints, change the latches. My nuclear option is move the CPU, PPU and NESRGB into a official motherboard as a test of the PPU. I don't think my logic analyzer and logic analyzer skills are up for more low-level debugging, but thats an option too.
friedskater
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by friedskater »

An update - I swapped out the switching regulator for a linear one. No discernable difference.

I took out the 74LS373 latch and swapped it for a 74HC373 and I think there is a very slight improvement. The player sprite is almost correct in Castlevania III (it was really corrupt before) and I get less glitching on the ED menu, especially on the bottom bar on the menu - there is no glitching there at all.

Unfortunately I don't have a way to capture 240p at the moment, so here's another crappy video of a TV screen https://imgur.com/a/jMIWNiu
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

friedskater wrote:An update - I swapped out the switching regulator for a linear one. No discernable difference.

I took out the 74LS373 latch and swapped it for a 74HC373 and I think there is a very slight improvement. The player sprite is almost correct in Castlevania III (it was really corrupt before) and I get less glitching on the ED menu, especially on the bottom bar on the menu - there is no glitching there at all.

Unfortunately I don't have a way to capture 240p at the moment, so here's another crappy video of a TV screen https://imgur.com/a/jMIWNiu
Good to hear the 74HC versions of U2 and U3 improved the Everdrive glitches. I will recommend these be used instead of the 74LS chips in my upcoming Youtube video and official documentation.

After thorough testing of the v1.2 NESessity it is now available for sale on https://www.tindie.com/products/low_bud ... s-console/
I am also working on fully assembled NESessity circuit boards (minus CPU & PPU.)

I have received many helpful suggestions from customers, some of which I was able to incorporate into v1.2
I made it a little easier to install the IGR board by adding solder pads for reset in/out and pads for all the controller pins.
I am not able to incorporate a Nintendo style A/V multi-out connector in the current design due to available room; However, I am now including a connection PCB for the s-video and 8p mini-DIN connectors included with the NESRGB. This PCB allows JST connectors to be used for the NESRGB to video out connection, which makes the install a bit neater.

I also added an "insert coin" button, but it doesn't quite work as intended, let me explain:
I was able to load some of the Nintendo Vs. arcade game roms (in .nes format) using the Everdrive, but I could not insert a coin in order to play them. So I found this helpful guide https://www.raphnet.net/electronique/ne ... ction_id=8 and decided to give it a try for v1.2.
So this was designed to have solder pads for a momentary pushbutton switch that would activate the coin input. My first test of the NESessity v1.2 I didn't install this switch. I loaded Vs. Super Mario Bros and I found that somehow the microphone input activates this. Yeah, tapping on or yelling at the NES will "insert a coin" and allow you to play Vs. Super Mario Bros. Weird. The color palette is wrong, because Nintendo used a primitive form of anti bootleg protection by using different pallete RGB PPUs in their arcade games.
Next I tried Duck Hunt. This game has the correct palette with a NES PPU. This game has audio glitches and I have yet to try the light gun, but it loads ok.
I also tried Vs. Castlevania, but could not get this game to boot. I am trying to locate more Vs. roms in .nes format to test out.

Anyway, there are still many limitations to playing the Nintendo Vs. arcade games, so I'm not advertising this as a feature. It does not interfere with NES / Famicom games whatsoever because they don't read D5 of the data bus when the player 1 inputs are being read. I also don't have the Vs. arcade game DIP switches, that may be causing some incompatibility.
friedskater
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by friedskater »

This sounds great.

regarding
low_budget wrote: Good to hear the 74HC versions of U2 and U3 improved the Everdrive glitches. I will recommend these be used instead of the 74LS chips in my upcoming Youtube video and official documentation.
I'm not sure I'd class the improvements as earth shattering, or even enough to convince me the issues are related to the latches. I still don't have a proper diagnosis or solution to my issues with the N8 menu or MMC5 games, but I asked another poster on Reddit who has the v1.1 board, albeit with different PPU and CPU revisions, to try the same games on their console. They did not have the video glitching issue with an original N8 - which is good, although I guess it suggest that I've made a mistake somewhere with my soldering!

I started to probe the PPU with a logic analyzer to see if there were any obvious differences adjacent between frames (the glitches flicker). I haven't found anything as of yet, other than to note that out of some 250,000 samples per frame about 4000 differ. The largest instances of differences between frames was on Pin 39 of the PPU / Address Latch Enable (ALE). I don't know much about the PPU - so this could be normal behaviour or timing variance. And it's been many years since my electronics degrees so I'm pretty rusty at this sort of thing. However, I noted that when I attached a probe to pin 39 (and only pin 39) the glitching clearly reduced. Suggesting to me that there is noise being introduced somewhere, and/or a bad connection to gnd/+5 somewhere. I resoldered all the pins on the PPU, the VRAM and the 373 Latch, but there was no change.

Oh, and I moved the PPU + NESRGB into an official front loader PCB - no glitching. I also tried an alternative PPU. That PPU also glitched in the NESessity and not with the official board.

[Edited to clarify that the tests performed by another v1.1 user were with an original N8 cart.]
Last edited by friedskater on Tue Nov 03, 2020 11:31 am, edited 2 times in total.
friedskater
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by friedskater »

There's been a discussion on Twitter today kicked off from a post by FirebrandX

https://twitter.com/FBXGargoyle/status/ ... 91712?s=19

Regarding compatibility issues with the N8 Pro and the NESRGB+IGR mod. These posts led me to this on the Everdrive forum

http://krikzz.com/forum/index.php?topic=9636.0

In which the OP has graphically glitches VERY similar to the ones I'm seeing with the N8 Pro on the NESessity, also on Castlevania III.

I wonder if these "bus stability" issues that Krikzz refers to are related to the problems I am seeing. I've now basically tried pretty much everything. Resoldered all the ICs. Even turned it into a PAL console. Glitches still there. Sadly I don't have an official NTSC Castlevania III cart to confirm whether that works.

[Edited to fix a spelling mistake]
Last edited by friedskater on Tue Nov 03, 2020 11:31 am, edited 2 times in total.
jd213
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by jd213 »

The original N8 has a history of glitches with the NESRGB as well: viewtopic.php?f=6&t=50313

I also got similar glitches fairly often when using the N8 on an AVS, no matter the firmware on the N8 or AVS. Was hoping the N8 Pro would be better on this front, but I guess it's not easy making something compatible with all the various hardware needed to make the NES output RGB or HDMI.
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

It looks like there is a new firmware update (released oct 25th) for the Everdrive N8 that has some nice new features including "Improvements for MMC5"

I will be testing that out shortly, although in my testing, I only experienced minor graphical glitches in the menus. Hopefully the issue has been fixed or at least improved.

EDIT: I updated the N8 pro firmware to the latest version and unfortunately the menu glitches still appear.

My next build of the NESessity I will substitute the 74HC139 and 74HC373 to see if I can get a noticeable improvement.
Zerorob
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by Zerorob »

Just finished mine Finally of V1.2 Love it so far. Added the Hi-Def NES HDMI kit, I am having one issue tho. Everytime I go to turn the system off, it stays on until I cycle the power switch again. Anyone else have this issue or have thoughts on it ?
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

Zerorob wrote:Just finished mine Finally of V1.2 Love it so far. Added the Hi-Def NES HDMI kit, I am having one issue tho. Everytime I go to turn the system off, it stays on until I cycle the power switch again. Anyone else have this issue or have thoughts on it ?
Are you using the Hi-Def NES kit's built-in regulator (replacing 7805 regulator) or are you powering the Hi-Def NES with 5v from the NESessity's 5v regulator?
Zerorob
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by Zerorob »

low_budget wrote:
Zerorob wrote:Just finished mine Finally of V1.2 Love it so far. Added the Hi-Def NES HDMI kit, I am having one issue tho. Everytime I go to turn the system off, it stays on until I cycle the power switch again. Anyone else have this issue or have thoughts on it ?
Are you using the Hi-Def NES kit's built-in regulator (replacing 7805 regulator) or are you powering the Hi-Def NES with 5v from the NESessity's 5v regulator?
Im using the Hi-Def kits built in regulator, I was having issues with my power supply before it seems to be 99% fixed tho, still does it the odd time. Somethings keeping it powered up, however its so infrequent now I am not to worried about it.

Couldn't be happy with this entire setup. Its incredible
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

I will soon have the NESessity v1.2 available in kit form. If anyone is interested in a pre-order please PM me; I will also offer kits on my Tindie listing.

Price will be $129.00 and does not include the CPU/PPU chips.
WinManX2000
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by WinManX2000 »

Any updates to this project? Curious to hear more input for using the N8 Pro with an NES RGB.
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

I have version 1.3 of the NESessity now available https://www.tindie.com/products/low_bud ... s-console/

I will also be offering the NESessity in kit form once the parts arrive.



Improvements over v1.2:

changes to the motherboard shape to allow a much larger heatsink for the 7805 linear regulator
extra solder pads on power switch connection, reset pins, and controller ports allow Borti's A/V power board replacement to be used
various trace optimizations and component footprint improvements


I have installed the NESRGB and IGR mod boards.  The wiring is a bit simpler as the extra 5v regulator included with the NESRGB is not needed and there are solder pads to connect the IGR mod. Since the NESessity uses the reset circuit from a top loader NES, set the "LO" jumper on the IGR.



I am also working on a NES - Neo Geo controller adapter.  Basically a standard controller circuit x2 wired to Neo Geo controller ports.  I hope to have this available soon.



Assembled v1.3 NESessity without CPU / PPU

Image

NESRGB and IGR (mostly) installed with correct points on the NESessity.

Image


This heatsink can easily handle the heat generated by a NES with NESRGB and a 7805 linear regulator.

Image


As far as the menu glitches on the Everdrive N8 and N8 pro, I don't think there is anything I can do design wise to the NESessity to fix this issue.
It seems to be an incompatibility between certain CPU / PPU chipsets and the Everdrive itself.
After I load games on the Everdrive they play fine without any glitches.
I regret selling my PowerPak because that flashcart had no issues.
WinManX2000
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by WinManX2000 »

Oh, wow. Thanks for the update. This is coming along nicely.

-ETA on when the full kits will be available?
-Any insight on what PPU/CPU combo the N8pro does not like?
friedskater
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by friedskater »

Version 1.3 looks great as ever. I wish I could justify another purchase, but with the UK import shenanigans and VAT changes that are going on right now I can't face it!
low_budget wrote: As far as the menu glitches on the Everdrive N8 and N8 pro, I don't think there is anything I can do design wise to the NESessity to fix this issue.
It seems to be an incompatibility between certain CPU / PPU chipsets and the Everdrive itself.
After I load games on the Everdrive they play fine without any glitches.
I regret selling my PowerPak because that flashcart had no issues.
I'm not 100% sure that it's a PPU/CPU issue, because my chips were socketed and I moved them into a stock motherboard and couldn't replicate the issues with the N8 Pro. In the end I put a PAL PPU/CPU/Crystal in my NESessity and it is now my main PAL deck, which I only ever use with official carts - since I'm in the UK most of my official carts are PAL ones. The N8 Pro is paired with my NTSC console and original motherboard.

I was never able to track down the glitch issue. For me it also happens with Castlevania 3 when loaded via the N8 Pro. I keep meaning to get myself 1) a proper Castlevania 3 cart to test that and/or 2) an oscilloscope which I think would be required for digging into the timing issues. I wondered if there was some slight different in the clock that was causing these glitches, but without an oscilloscope to confirm that's just guesswork. I would be interested to know if anyone with a NESessity has glitches when using an official Castlevania 3 MMC5 or Akumajō Densetsu VRC6 cart.
friedskater
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by friedskater »

WinManX2000 wrote: -Any insight on what PPU/CPU combo the N8pro does not like?
I get graphical issues on the N8 Pro menu - flickering horizontal lines. All games work fine, with the exception of VRC6 and MMC5 games, which also have graphical issues. I don't have carts of these games so I can't confirm if they have the same issues when not loading via the N8 Pro. Castlevania 3 is the only real big hitter than I have issues with. I think there are only about 9 or 10 games that use these mappers, but I've not tried them all.

I've tried multiple PPU/CPU combos, including PAL ones. All have graphical glitches to some extent. At some point I'll pop open my consoles and see what versions they are. I did recently pickup a new Famicom. If the chips are different it might persuade me to desolder the PPU on that to check.
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mrsmiley381
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by mrsmiley381 »

So I recall a while back on 4chan's /vr/ board that some dude was absolutely livid that his NES refused to work with MMC5 games after he installed a Blinking Light Win in his console. His argument was that the BLW's connections used thinner wiring/traces than a stock 72 pin connector, thus introducing resistance high enough that it introduced interference between the game and console. Curiously, I can't find too much info regarding this problem, but I have seen other posts where people had problems with their consoles until they switched to a replacement power adapter.

Just a couple thoughts for troubleshooting issues. If all the wiring in the NESessity is up to spec or better compared to the original console then maybe that's not the issue.
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low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

I can confirm Castlevania 3 US cart works, I will test the Japanese version cartridge once I get a Famicom adapter.

I have about 30 original NES cartridges and I tested about 20 of them; these all worked well and without graphical glitches. Some of the games I had to give a good cleaning first though.

The blinking light win does have some narrow traces, but I only see this as an issue if the 5v and ground are not thick enough for the Everdrive's power consumption. I'm somewhat curious how much power the Everdrive Pro cart draws.

While the NESessity is fully compatible with the original NES AC adapter, when adding things that use additional power like the Everdrive, NESRGB, etc it's good to get a 12v adapter that can supply 2A.

I don't have a large variety of CPU / PPU chips on hand, but maybe the theory of certain ones being the problem [with Everdrive glitches] is not correct.

The clock circuit used on the NESessity is the same schematic as the NES top loader, just different transistors are used. I have used 2 different clock circuits on the NESessity and haven't found any differences between them. NESessity v1.0 - 1.1 use the front loader's more complex clock circuit.
WinManX2000
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by WinManX2000 »

Do you have full kits back in stock? Any plans for a 1.4? Not that I am seeking any changes. Just curious.
Weareattack
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by Weareattack »

I built a NESessity 1.3 recently and have been using the composite video on a crt.

My famicom cart of Castlevania 3 seems fine. I haven’t seen any glitching. I used two different FC to NES converters, along with the original 72pin and blinking light win. I don’t have an Everdrive N8 Pro unfortunately.
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

I have updated my NESessity v1.3 parts list due to several components being out of stock or end of life.

https://atariage.com/forums/application ... ?id=829872

I don't have any changes planned for future versions of the NESessity. If I think of any meaningful upgrades before I order the next batch of PCBs, I will implement them.

I am nearly out of the digikey parts kits, so it will be some time before I have more available.


I also have NES - Neo Geo controller adapters available https://www.ebay.com/itm/Adapter-to-use ... OSw5FxgTNX~
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by jbrlll »

I just did a 1.3 with NESRGB, IGR, YPbPr. I also had menu glitching on the N8pro and castlevania lll graphical errors. Much worse on a LCD, crt dealt with it much better both via HD retrovision component cable and retro access Nintendo multi out to jp21 RGBS cable. Castlevania lll original cart plays perfect. I socketed my cpu, socketed the actual NESRGB board and socketed the ppu, cut the bottom of the case for clearance. Popped in an arrangement of cpu and ppu chips with identical results. I was just sharing if that info helps at all, I believe I had the HC ox’s but need to verify. The best improvement I’ve seen is using the Triad 2amp 9v 2000-R, i think that N8 likes the nipple. I love the setup.
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

I am working on a "no cut" A/V power board that will allow composite video, s-video, stereo sound, and RGB output connectors with no case modifications.

I am thinking of having s-video and a 9p mini DIN connector (Genesis 2 pinout) on the side, while RCA composite and 1/8" stereo audio output on the back.

While I would like to make this compatible with original NES motherboards also, I like the large heatsink I am using on the 7805 and that would not fit an original NES motherboard without cutting. So it looks like this board will only work with the NESessity.
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by pixeltao »

I built the NESessity board v1.2 with NESRGB a while back.

It worked perfectly for about 1 month of pretty intensive use: I finished Zelda II and almost finished the Famicom version of Castlevania III on it.

However my PPU died when I was close to finishing Castlevania III.

Just before it died, the symptoms were really strange and not seemingly related to the PPU: the music started playing at double speed and graphics were all offset down in relation to the collisions.

I'm wondering if it's only bad luck or if something could have caused it to die. 2 things I suspect could have caused it:
  • 1- A couple days before it died, I switched my OG power supply for a Triad 9V, 1.3 amps, center-positive.
    2- I was outputting composite video to both the RCA port and the multi-out. Could it have put too much pull on the PPU even though only one output was used at once?
Any pointers would be appreciated.

I ended up removing the NESRGB and putting in the composite amp circuit and a clone PPU and it's alive again, so nothing else died at least. I'd like to re-add an original PPU at some point, but since I'm unsure what killed it, I wouldn't want to destroy another original chip.

Nevertheless, it was a really fun project to build. Since then I've also built an OpenTendo with NESRGB which was also fun and is still kicking.

It looked like this before I removed the NESRGB board:
Image
low_budget
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by low_budget »

The NES CPU has the sound hardware built-in, so it seems your issue may be CPU related.

In my experience, PPU failure usually results in a solid color screen (usually black,) or will display with missing colors.

I believe the NESRGB composite video out only supports one TV or monitor connected at once. Wiring the composite video output to two connectors wouldn't hurt anything as long as only one TV was hooked up.

I don't think the AC adapter would have caused issues, but the NESRGB draws additional current and I like to use an AC adapter 12v rated at 2A.
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by pixeltao »

low_budget wrote:The NES CPU has the sound hardware built-in, so it seems your issue may be CPU related.

In my experience, PPU failure usually results in a solid color screen (usually black,) or will display with missing colors.

I believe the NESRGB composite video out only supports one TV or monitor connected at once. Wiring the composite video output to two connectors wouldn't hurt anything as long as only one TV was hooked up.

I don't think the AC adapter would have caused issues, but the NESRGB draws additional current and I like to use an AC adapter 12v rated at 2A.
Thanks for the heads up, I appreciate it! Yeah it makes sense, and now that I think about it, I also had some audio issues while playing Zelda II. In towns, I had some missing channels once or twice. So, after I got those CPU related glitches, the PPU was completely dead, but the CPU appears to still be working... So now I'm wondering if the CPU, while not dead, has some issue that could have contributed to kill the PPU. I'll swap the CPU and do more tests before putting in another original PPU.

Cheers!
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Re: Introducing the NESessity NES front loader PCB replaceme

Post by Spook50 »

Posting in this thread rather than starting a new one and cluttering up the forum; on all versions of the NESessity (mine being a 1.4) there's a location for a trimmer cap (TC1, near the expansion port on the component side). I haven't seen any mention of it in any documentation or install videos, so I'm curious as to its purpose and what it needs to be adjusted/calibrated to (if at all) on installation. Any thought?

Edit for anyone else who may have been curious as well: was informed the trimmer cap is for dialing in video quality when using a composite connection after assembly is complete.
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