N64 RBG - Sync Questions (PAL)

[RaphM]

Hi,

I am planning to apply the N64RGB mod (v1.2) to my old PAL N64 and am now done going through the initial research (especially the guide at http://etim.net.au/n64rgb/instructions-new/ and the general info provided at http://www.retrorgb.com/).

I understood all the basics, but have some open questions regarding sync that I was not able to deduce from those resources.

The "basic" setup (as described in "Finishing Off" section @ http://etim.net.au/n64rgb/instructions-new/) will look like:

* J1, J2, J3 soldered (as I plan to use SNES PAL scart cables)
* Wiring:
1 <-> RED
2 <-> GREEN
4 <-> BLUE
5 <-> GND
6 <-> GND

Now to my questions:

* Using this cable I should have working SYNC on LUMA without further modifications - correct?

But if I wanted CSYNC using this cable I have to perform more modifications:

* Option a): Cut the track to pin 9 and wire up 9 <-> CS75 instead - will this work? (keeping PAL in mind - I am not sure whether the guide takes this account, hence my question)

* Option b): Quoting from the guide: The second solution is to rewire the cable to use either pin 7 (luma) or pin 3 (normally not connected - connect CS75 or CS# signal here from the N64RGB) for sync.

I am totally lost on this one, what is meant by "rewiring the cable", what are the exact steps I need to perform to get CSYNC using the linked cable? (again keeping PAL in mind)

[borti4938]

Personally I use a cable with 'sync on luma'.

• If sync on luma works with your N64 depends on your N64. Early PAL-N64s outputs S-Video on pin 7 and 8, later PAL-N64s has grounded these pins.
• What I have done is:
  • free pin 7 (i.e. cut the trace to this pin which is either luma or gnd (see first point))
  • solder CS75 to pin 7
• In that way you would have raw composite sync with a sync on luma cable

So please, use the first cable you reference. You will have raw sync as wanted!

The second cable is nothing else but a sync on luma cable with a LM1881 build in the SCART plug. The sentence "to avoid eradicate the checkerboard effect" is not true, because this checkerboard effect is caused by crosstalk with sync-wire (where we have luma in this cable) within the cable and not at the very end. This cable is only useful if and ONLY if you have an unmodified PAL SNES (i.e. 12V at pin 3 of the MultiAV) and if your TV set needs raw sync. If ones TV set does not need raw sync this cable is nonsense.

[RaphM]

Thanks, this is a great suggestion I would have never been able to come up with by myself based on the available resources - but what else to expect from the author of the de-blur feature for that mod .
Just to make sure I understood it correctly:

* It doesn't matter whether I have a new or old PAL N64, freeing pin 7 and then wiring 7 <-> CS75 and using this cable will effectively get me CSYNC?

[borti4938]

Correct

[H6rdc0re]

I also want to do the same installation with the same cable. Do I need to solder GND and if so to which pin because there are 2 pins carrying GND? Or would 4 wires to Red, Blue, Green and CS75 with pin 7 trace cut be enough?

[borti4938]

GND is GND - so it doesn't matter whether you use pin 5 or 6 for it...
You have connected GND to the modding board along with the wires for the digital data anyway. However, having more GND wires means that you reduce the noise on the video lines.

See also here: http://shmups.system11.org/viewtopic.ph ... 9#p1242049

[chomel]

The second cable is nothing else but a sync on luma cable with a LM1881 build in the SCART plug. The sentence "to avoid eradicate the checkerboard effect" is not true, because this checkerboard effect is caused by crosstalk with sync-wire (where we have luma in this cable) within the cable and not at the very end. This cable is only useful if and ONLY if you have an unmodified PAL SNES (i.e. 12V at pin 3 of the MultiAV) and if your TV set needs raw sync. If ones TV set does not need raw sync this cable is nonsense.

Sorry if I'm off topic, but for an unmodified SNES using sync on luma or sync stripper (on composite video, pin 9) provides the same quality on a regular LCD TV?

[H6rdc0re]

GND is GND - so it doesn't matter whether you use pin 5 or 6 for it...
You have connected GND to the modding board along with the wires for the digital data anyway. However, having more GND wires means that you reduce the noise on the video lines.

See also here: http://shmups.system11.org/viewtopic.ph ... 9#p1242049

Thanks Borti!!!