NESRGB board available now

[ms06fz]

As far as I understand it VERY BAD IDEA. The NES creates DC from AC using bridge ractifier using diodes. The power input is 110V/220V AC with output being DC. It is then converted to 5V DC using the power regulator. A big cap is included to make the AC pulses smooth for DC.

My point? Those eBay diodes are only rated for 50V!! You'll blow them.

The NES only takes 10V AC in. So 50V rating on the diodes should be plenty.

[TheRetromancer]

As far as I understand it VERY BAD IDEA. The NES creates DC from AC using bridge ractifier using diodes. The power input is 110V/220V AC with output being DC. It is then converted to 5V DC using the power regulator. A big cap is included to make the AC pulses smooth for DC.

My point? Those eBay diodes are only rated for 50V!! You'll blow them.

Leonk, that would only be true if the voltage running into the NES was 230V. The transformer in the AC Adapter drops that to about 10V. 50V is WAY overpowered. He'll be FINE.

Voltage regulators work by taking excess voltage and dispersing it as heat energy. Using a regulator to drop 225V is absurd. Even if we make the radical assumption that the voltage regulator wouldn't simply catch on fire from this sort of heat, the ground plane on the circuitboard would likely generate enough heat to melt through the plastic, and would certainly cause damage to the components on the board itself.

Chill, my well-meaning but panicky friend.

[juji82]

Hello again. I can get a sharp twin famicom but there are two models, 505 or 500R f i remember correctly.Any big differences?

[ApolloBoy]

Hello again. I can get a sharp twin famicom but there are two models, 505 or 500R f i remember correctly.Any big differences?

Aside from the turbo controllers and power LED in the AN-505 models, there's no real significant technical differences between the two. Certainly none that would complicate an NESRGB install.

[juji82]

Thanks for you fast answer!

[lettuce]

Just be absolutely sure that you mount the diodes in CORRECTLY - the cathode (-) end has a white marking around it, and should always go into the hole nearest to the vertical line of the 'diode symbol', NOT the side that is near the arrow.

Ok diobes have turn up today, whats said above have noticed that the diodes installed already in the NES seem to have the band of the diode connected to the positive side???......



EDIT: Noticed that the 2 middle diodes are designed to be the opposite way around to the outside diodes......

[lettuce]

Ok trying to fault find on my NESRGB to see if it got fried or not. I have tested the connections where you solder the pins that you plug into the NES main board and the solder points where you connect the PPU chip to on the NESRGB with a multimeter. I am getting a reading from all solder sockets and pins apart from DP0, DP1, PD2, DP3, DP4, DP5, DP6 DP7 on the NESRGB, are you supposed to get readings from these sockets when testing?

[mvsfan]

do you have another ppu you could put directly in the nes first to test it and make sure something isnt still bad in the nes?

[lettuce]

do you have another ppu you could put directly in the nes first to test it and make sure something isnt still bad in the nes?

Ive got some universal PPU chips...

http://www.arcadecomponents.com/catalog ... 583135.htm

I solder some pin sockets to the NES main board so i can easily swap in and out PPU chips without having to solder them, have removed the NESRGB completely and plugged one of the PPU chips in the socket on the NES mainboard, have tried 2 games and all i seem to be able to get is a scrambled graphics on the screen the music sounds fine however, i take it those PPU chips are universal.

So i guess this NES has had it??

[mvsfan]

I looked at those ppus. they are ntsc us ppus.

you are in the UK. are you using a PAL nes? the pal nes uses an rp2c07 ppu. It probably explains your glitches. I bet your nes is working fine.


also the cart connectors are always touchy in these things unless they are brand new. Almost every front load nes i get in when i first turn it on it has a garbled graphics / or blinking problem because of a dirty or loose cart connector. it will stay like that until i replace the connector.

[lettuce]

I am using a NTSC NES console and have also replaced the 72 pin connector with a new one. I have also tried another NTSC PPU from a different console and still get the same messed up screen.

I have just been inserting the PPU into the socket connection that you installed to plug the NESRGB into, so the PPU can easily be removed and replace with another one, unless the PPU pins aren't all making a good contact when inserted into these socket connectors (that you usually plug the NESRGB into) but it seems to fit snuggly??

[mvsfan]

I had noticed on the first nes i did that the ppu wasnt really making good contact in the round pin headers and i was getting glitches. I didnt have any problems testing it out when i plugged the ppu directly into the nes board though using the round headers that tim supplied.

the problem only showed up when i tried to use the round headers as a ppu socket on the nesrgb.
Soldering the ppu directly to the nesrgb solved the glitches.

[viletim]

I had noticed on the first nes i did that the ppu wasnt really making good contact in the round pin headers and i was getting glitches. I didnt have any problems testing it out when i plugged the ppu directly into the nes board though using the round headers that tim supplied.

the problem only showed up when i tried to use the round headers as a ppu socket on the nesrgb.
Soldering the ppu directly to the nesrgb solved the glitches.

The round pin sockets are not really meant for IC legs. I see a lot of people use the dual wipe socket for the NESRGB and the round pin socket for the PPU when it's supposed to go the other way around. I should make it more clear in the installation guides perhaps?


lettuce,

I can't really comment on your NES, but there is a fairly simple test you can do to the NESRGB board. First pull it out of the NES, it doesn't matter if there is a PPU soldered onto it or not. Then use a multimeter to measure the resistance between ground and pins 1-19 where the PPU goes. All of the should measure > 1M except for pins 14-17 (EXT0-3) which should be about 10k. Also measure pins 2-7 of the NESRGB pins (DB0-7) which should be > 1M. If you measure a low resistance at one of these points it would indicate a damaged NESRGB board.

[lettuce]

Thanks for the suggestion, ill try testing the NESRGB. I guess i should either solder the PPU directly back to the mainboard or get some of those dual wipe socket. What size dual wipe socket would i need?

Viletim, any plans to make the NESRGB with socket connection for the PPU chip in future revisions rather than solder holes???

EDIT: ok have test pins DP0 -DP18 for 1M resistance and got no ready, test EXT0-EXT3 and got 10k readying and finally tested DB0-DB7 and got no reading at all

[eightbitminiboss]

I had noticed on the first nes i did that the ppu wasnt really making good contact in the round pin headers and i was getting glitches. I didnt have any problems testing it out when i plugged the ppu directly into the nes board though using the round headers that tim supplied.

the problem only showed up when i tried to use the round headers as a ppu socket on the nesrgb.
Soldering the ppu directly to the nesrgb solved the glitches.

The round pin sockets are not really meant for IC legs. I see a lot of people use the dual wipe socket for the NESRGB and the round pin socket for the PPU when it's supposed to go the other way around. I should make it more clear in the installation guides perhaps?


lettuce,

I can't really comment on your NES, but there is a fairly simple test you can do to the NESRGB board. First pull it out of the NES, it doesn't matter if there is a PPU soldered onto it or not. Then use a multimeter to measure the resistance between ground and pins 1-19 where the PPU goes. All of the should measure > 1M except for pins 14-17 (EXT0-3) which should be about 10k. Also measure pins 2-7 of the NESRGB pins (DB0-7) which should be > 1M. If you measure a low resistance at one of these points it would indicate a damaged NESRGB board.

It looked pretty obvious what goes where during my install, but clearer directions wouldn't hurt.

[Pasky]

Update on my issue with Final Fantasy's color emphasis when entering a battle from a first batch NESRGB. Customs finally let me have the USB Blaster Tim sent, updated it to 1.4 and the issue is no longer there. So if anyone ever had a similar problem, use the update.

Thanks.

[antron]

^ I haven't been keeping up with this issue, but I guess I need to since I have the launch model (which I haven't installed yet)

Are there any instructions? Firmware link?

[eightbitminiboss]

^ I haven't been keeping up with this issue, but I guess I need to since I have the launch model (which I haven't installed yet)

Are there any instructions? Firmware link?

All here: http://etim.net.au/nesrgb/background_fault/

[antron]

Thank you. Anyone have a spare usb blaster?

[darcagn]

Thank you. Anyone have a spare usb blaster?

eBay now has a seller for $9 shipping from within the USA.

[antron]

And... purchased.

Thanks y'all!

[CkRtech]

Could you guys verify something for me - If you are playing a NES game and see a single horizontal line of garbage quickly flash across 1/3 or 1/2 of the horizontal width of the screen, is that one of the many artifacts of a dirty cart connector? I am in the process of cleaning all of my games. I noticed it before I started cleaning, but I seem to still see it after I am cleaning. I am fairly certain it is a cart connector-related thing, but I thought I would check in.

Granted - this is a front loader, so anything goes when it comes to cleaning/stabilizing that cartridge connector.

[leonk]

Could you guys verify something for me - If you are playing a NES game and see a single horizontal line of garbage quickly flash across 1/3 or 1/2 of the horizontal width of the screen, is that one of the many artifacts of a dirty cart connector? I am in the process of cleaning all of my games. I noticed it before I started cleaning, but I seem to still see it after I am cleaning. I am fairly certain it is a cart connector-related thing, but I thought I would check in.

Granted - this is a front loader, so anything goes when it comes to cleaning/stabilizing that cartridge connector.

Depends on the game, I see garbage on the right side of the screen, as the screen scrolls. This is especially visible in Super Mario Bros 3. It was discussed before, the NES always had issues with junk while scrolling. Most people didn't notice it at the time on 13" TVs connected via RF.

[mvsfan]

it sounds like your getting an awful lot of garbage on screen if its going halfway across!

On mine its normal to see a couple blocks on the right side of the screen as you scroll. its really noticable on super mario bros. in the overworld. It looks to me like the game is scrolling faster than the ppu can keep up with - thats the effect i get from it.

I believe its a lot more noticable on RGB than it would have been years ago on RF when we rememember playing it.

perhaps someone else can fill in the details of WHY it does this.

[CkRtech]

It isn't really a screen scroll or side garbage thing. It is a quick blink of only one pixel tall of a line that takes up like 30-50% of the screen. It flashes for just a split second and disappears. I looks like one particular line of the game has been copied and shifted into a different x,y position. I simulated it using a googled image of Zelda II (the most recent game I experienced it on):

[Zets13]

I cannot say for sure if that is normal for Zelda II, but I know that glitch lines like that do occur in SMB and it is normal behavior...

[mvsfan]

antron wrote:
Thank you. Anyone have a spare usb blaster?


eBay now has a seller for $9 shipping from within the USA.


with that usb blaster - youll have to first hook up the usb blaster to the nesrgb and then power it from the nes (plug nesrgb into nes and turn it on)

if you dont want to have to power it from the nes youll have to modify the usb blaster.

also i had trouble getting quartus to work with windows 7. i tried XP and it worked. But i later figured out that i had the driver installed wrong in 7. I got it working with 7 and was able to program my other boards in win 7.

[Voultar]

So I just tested a plethora of shielded S-Video cables with both my v1.3 NESRGB Twin Famicom, and Front Loader. It has done nothing to help with the diagonal lines issue.

To help eliminate various components from being the culprit of this issue, I decided to quickly wire up my EXTERNAL RGB to S-Video/Composite encoder.

This little board is pulling RGB+Sync directly from the NESRGB outputs.




And wouldn't you know, even when externally encoding RGB to S-Video/Composite, the diagonal lines are still there. (Yes, I used multiple different sources for Sync, including CS)



Ultimately, I'm out of idea's. Contrary to what Tim stated, I know it isn't my cables, nor is it a grounding issue. That's been verified. So what else can we look for, other than the NESRGB itself? All of my testing is indicating that it is in-fact a problem residing within the NESRGB.

[TheRetromancer]

EDIT - Whoops. Missed where you said that you'd tried in your frontloader.

[Pasky]

It's a lot of work, but if you had another NES to install the NESRGB on and see if that interference still occurs, that could rule out if it's the NESRGB or the NES itself.