N64RGB installation troubleshooting

[Zepherino]

Hi there,

I recently installed Tim's N64RGB onto my N64, and I'm having trouble with getting the mod working with my displays (SONY PVM 20M2U, BVM 20F1U). It looks like some sort of sync issue, but I don't know for sure, as I'm a total novice with this.

http://imgur.com/a/oEnka

I have a SNES Mini with Voultar's board, which works well with my monitors, and I tried using the same SCART cable (a cheapo generic found on Ebay) on my N64, and the result is what you see on the above photos.

I've also included photos of the installation for reference below. I desoldered and resoldered the ribbon cable from the VDC chip once, thinking at first that the problem may have been poor soldering, but the result was unchanged.

http://imgur.com/kERtxhp
http://imgur.com/a/lXR6b

Any assistance with this, or referral to other threads that might help with my issue would be greatly appreciated!

[Thomas83lin]

Definitely missing sync. I'm not sure how your current cable is wired for sync but N64's have csync disconnected\removed except for early models.

Easiest fix would be to get a sync on luma rgb cable. or figure out how your current cable is wired for sync and restore sync to your N64 accordingly using CS# or CS75.

[Zepherino]

Thanks for the quick response!

Looks like you're right on my N64 missing CSYNC. I figured I had a very early model of N64, but not early enough.

Is the process to restoring CSYNC to my N64 simple, or would it be better to just get a sync on luma cable? If I get a sync on luma cable, would I need to solder more wires on onto the N64RGB board? I think Tim's install instructions mentioned something about this, but it isn't very clear for me on this step.

[Ikaruga11]

So wait, CSync is only available on early N64s? Even Tim's board can't provide CSync?

[Thomas83lin]

Thanks for the quick response!

Looks like you're right on my N64 missing CSYNC. I figured I had a very early model of N64, but not early enough.

Is the process to restoring CSYNC to my N64 simple, or would it be better to just get a sync on luma cable? If I get a sync on luma cable, would I need to solder more wires on onto the N64RGB board? I think Tim's install instructions mentioned something about this, but it isn't very clear for me on this step.

If you got a sync on luma cable you would not have to do any more soldering. restoring csync is simple enough Tims instructions should mention this.

I'm betting you have a CPU-04 n64, so soldering a wire from CS75 straight to pin 3 on the multi out might be all that's needed. Make sure not to do this if you have a PAL N64 as pin 3 outputs 12volts on PAL N64's. This is all assuming your cable is wired for csync.

So wait, CSync is only available on early N64s? Even Tim's board can't provide CSync?

Yes tims board output csync. Some early N64's output csync without any modification

[Zepherino]

Your guess is correct! I do have a CPU-04 model.

Soldering a wire between pin 3 and CS75 also did the trick! Thanks your the help.

Tim's instruction did mention wiring either pin 3 or 7 over to CS75 or CS#, but it wasn't clear on when this was required, or what exactly it would do for sync. Additionally, his photos also only showed the R,G,B and ground pads soldered on his board, which caused the confusion for me.

[bobrocks95]

If your SCART cable doesn't have any components in-line with the sync signal you need to use CS75. If it has resistors and such, you should probably use CS#

[Thomas83lin]

If your SCART cable doesn't have any components in-line with the sync signal you need to use CS75. If it has resistors and such, you should probably use CS#

This is true but its a little more complicated than just switching over to CS#
by default its my understanding that CS75 and CS# are both designed to work with a 75 ohm video input.

See the CS# isn't true TTL, because it contains a 330ohm resistor in series at R52 on the rgb pcb board bringing it down to a proper level.

So lets say your using CS# and a snes rgb cable that already contains a 330ohm resistor on csync So in order to compensate you would need to find R52 on the rgb pcb board which is a 330ohm resistor and bypass it. in the end you only want around 330ohm on csync. (I actually had this same setup myself and this is what Tim suggested to me in a email.)

So lets say you didn't bypass R52 on the rgb pcb, you would have 330 from the cable and 330 from R52 giving you 660ohm on csync. In the end if CS75 is working fine, you should be fine. If it isn't you can use CS# but you may still need to tweak the resistance on csync.

@viletim If i need to be corrected about anything let me know.

[speedlolita]

I just bought a NUS-CPU-01 to install my N64RGB in. I'll be using an official GameCube SCART lead - would using the csync that the console makes be automatically fine or would one of the two options on the N64RGB be preferable for sync?

I'll be isolating the usual composite video pin and tapping my csync to that. Cable will not be modified.

[Thomas83lin]

I just bought a NUS-CPU-01 to install my N64RGB in. I'll be using an official GameCube SCART lead - would using the csync that the console makes be automatically fine or would one of the two options on the N64RGB be preferable for sync?

I'll be isolating the usual composite video pin and tapping my csync to that. Cable will not be modified.

The only thing I'd be worried about is whether the early models n64's csync is TTL strength or not. I'm not 100% sure, but I know that since your cable was meant for composite video sync it wouldn't have the necessary components if it was TTL. isolating the composite video pin and using cs75 might be the safer choice.