NAOMI VGA (LOW RES SETTING) TO ARCADE STANDARD MONITOR

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 6:23 am

Friends,

I think hook my Naomi on a standard arcade monitor on this way. Working??

(see the picture..)

http://picasaweb.google.com.br/lh/pho ... rectlink

Tks!

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 9:39 am

No, this will probably not work. You cannot combine Horizontal and Vertical sync by just connecting the two. I suspect the RGB input on your monitor has R, G, B, Ground, Composite Sync?

If this is the way you want to connect your Naomi, you will need a circuit that can convert the two timing signals into a composite one, for example like this: http://www.epanorama.net/circuits/vga2rgbs.html

What is it you are trying to accomplish? Why not use a Capcom or Sega I/O to connect the Naomi to a JAMMA cab?

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 5:13 pm

There is no need to convert VGA to RGB when the Naomi does this by simply flipping a switch. There are generally 5 connection points on a standard 15k monitor: R,G,B, Ground and sync. A standard arcade monitor does not generally require both Horizontal and Vertical syncs (like VGA) and 15k games don't give both neither.

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 7:27 pm

aha.. so in fact you could connect the two signals in that case, if I understand what you are saying?

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 7:42 pm

No, there is no need because the Naomi gives only one sync just like JAMMA games. The standard Naomi Jamma I/O has a DB15 connector which directs the 15k video signals to the Jamma edge without modification. All you need to do is flip dipswitch 1 to 'ON' and the games will automatically display on your standard monitor.

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 7:49 pm

That part I understand; My question was more related to the question that Cobr4a asks, since he wants to connect the Naomi VGA directly to a monitor.

OldFoo · Post by **OldFoo** » Fri Sep 25, 2009 11:28 pm

Here's my reasoning:

a) He wants to connect the Naomi to a standard arcade monitor

b) These monitors are generally used with Jamma pcb's

c) If he's using Jamma pcb's, he probably has a Jamma harness

d) A Jamma harness has the necessary RGB connector (usually)

e) Using a Naomi Jamma I/O adapter will connect the VGA cable to the monitor

Why does he want to bypass all of this to connect the Naomi directly to the monitor? It's just more work and headache.

OldFoo · Post by **OldFoo** » Sat Sep 26, 2009 10:06 am

joshua3dg wrote:Why does he want to bypass all of this to connect the Naomi directly to the monitor? It's just more work and headache.

I agree. I asked the same question:

Cageman wrote:What is it you are trying to accomplish? Why not use a Capcom or Sega I/O to connect the Naomi to a JAMMA cab?

So, Cobr4a: you now have a wealth of information. Enlighten us with more insight in what you are trying to do?

OldFoo · Post by **OldFoo** » Sat Sep 26, 2009 8:59 pm

Cageman wrote:
joshua3dg wrote:Why does he want to bypass all of this to connect the Naomi directly to the monitor? It's just more work and headache.

I agree. I asked the same question:

Cageman wrote:What is it you are trying to accomplish? Why not use a Capcom or Sega I/O to connect the Naomi to a JAMMA cab?

So, Cobr4a: you now have a wealth of information. Enlighten us with more insight in what you are trying to do?

I need connect the Naomi VGA output direct to RGB+ground+Sync connector on the arcade monitor. I can do this only setting naomi 15k dip on? H-Sync and V-Sync twisted to Sync monitor in?

Thanks so much!

OldFoo · Post by **OldFoo** » Sat Sep 26, 2009 9:06 pm

Cageman wrote:aha.. so in fact you could connect the two signals in that case, if I understand what you are saying?

Cageman, then I can twist H-Sync and V-Sync on Naomi output VGA if I set dip to 15k on naomi motherboard? It will work?

Thanks.