Getting the H and V sync on VGA to pass through to green on 13W3
#1
Getting the H and V sync on VGA to pass through to green on 13W3
Hey dudes,


I read in a few places that you can get the horizontal and vertical sync pins on a VGA cable to pass through over 13W3's green pin through resoldering,
So: 
1. What pinout do I need to resolder to?
2. Do I still need an SoG capabled monitor?

I found on this thread: (http://forums.irix.cc/thread-382.html) that a man named Michael sold a few cables which had this mod done to them,
and he claimed that it worked regardless of the monitor's SoG, the original ebay listing Michael posted is here:(https://www.ebay.com.au/itm/282825956507?ul_noapp=true)

Another thread from 2009 claims you can use a circuit to strip the sync signal from the green channel: (http://www.vcfed.org/forum/showthread.ph...c-On-Green)

Cheers for your helps bros, you all seem really tight knit especially for an online community :)

I wish I had any SGIs to show :( 


PM me if you have cheap Octanes or Indigo2s, I might be able to work out a deal with you,
But I'm broke so don't hold your breath LOL
fakkoitto
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03-19-2019, 12:20 PM
#2
RE: Getting the H and V sync on VGA to pass through to green on 13W3
A page on creating such a circuit is shown in https://www.raphnet.net/electronique/syn...een_en.php

As for your questions:
1) 13W3 pin usage towards the monitor side doesn't need anything other than the three colors and their ground if you use SyncOnGreen. The other-way-around question of what is the pinout from a SGI depends on the SGI, since some of these systems differ in assignment of the 10 small pins in between the larger color leads.
2) Well, if you want to combine sync to the sync on green channel, then yes Smile see our thread on http://forums.irix.cc/thread-382.html
dexter1
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03-25-2019, 01:08 PM
#3
RE: Getting the H and V sync on VGA to pass through to green on 13W3
(03-25-2019, 01:08 PM)dexter1 Wrote:  A page on creating such a circuit is shown in https://www.raphnet.net/electronique/syn...een_en.php

As for your questions:
1) 13W3 pin usage towards the monitor side doesn't need anything other than the three colors and their ground if you use SyncOnGreen. The other-way-around question of what is the pinout from a SGI depends on the SGI, since some of these systems differ in assignment of the 10 small pins in between the larger color leads.
2) Well, if you want to combine sync to the sync on green channel, then yes :) see our thread on http://forums.irix.cc/thread-382.html

Cheers Dexter, ur a massive help :)

I wish I had any SGIs to show :( 


PM me if you have cheap Octanes or Indigo2s, I might be able to work out a deal with you,
But I'm broke so don't hold your breath LOL
(This post was last modified: 03-25-2019, 08:55 PM by fakkoitto.)
fakkoitto
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03-25-2019, 08:55 PM
#4
RE: Getting the H and V sync on VGA to pass through to green on 13W3
I'm not that good with electrical stuff, I can solder a bit but using an oscilloscope is way out of my field of knowledge LOL

But I have another idea. I have a TV with an RCA RGB input, which means to my understanding it sends a sync pulse on green, and is electrically compatible with the 13W3 video on an Indigo2 or Octane, because to my understanding they only use the colour and colour ground pins on their 13W3 connector. So - in theory I should be just be able to buy Ian Mapleson's 13W3 to BNC box (http://www.sgidepot.co.uk/sgidepot/moncab.html [click on the blue hyperlink for the breakout box]), buy a few BNC cables (https://www.ebay.com.au/itm/BNC-Male-to-...O&LH_BIN=1) and a set of just under a dozen BNC to RCA converters used in security cameras (because it's cheaper than just buying 3) (https://www.ebay.com.au/itm/182364249686...Track=true) and plug it all in it should work

It's not as ideal as a CRT solution, as Irix to my knowledge looks shit on an LCD panel, but it's workable until I can figure out a better solution for video :)

Quick Edit: I should say by RCA RGB I mean 3 video cables: red, green and blue: not the single yellow cable, I call that RCA composite

I wish I had any SGIs to show :( 


PM me if you have cheap Octanes or Indigo2s, I might be able to work out a deal with you,
But I'm broke so don't hold your breath LOL
(This post was last modified: 03-26-2019, 06:25 AM by fakkoitto.)
fakkoitto
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03-26-2019, 06:23 AM
#5
RE: Getting the H and V sync on VGA to pass through to green on 13W3
I'm gonna pick up one of these cables and see if it's really as "magic" as it looks to be  :huh:

https://www.pccables.com/products/00633.html
pcar
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03-29-2019, 04:12 AM
#6
RE: Getting the H and V sync on VGA to pass through to green on 13W3
(03-29-2019, 04:12 AM)pcar Wrote:  I'm gonna pick up one of these cables and see if it's really as "magic" as it looks to be  :huh:

https://www.pccables.com/products/00633.html

Ye it sounds pretty fake, but I damn hope it works LOL

I wish I had any SGIs to show :( 


PM me if you have cheap Octanes or Indigo2s, I might be able to work out a deal with you,
But I'm broke so don't hold your breath LOL
fakkoitto
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04-06-2019, 11:08 PM
#7
RE: Getting the H and V sync on VGA to pass through to green on 13W3
I finally got my new (to me) Octane2, I am pleased to report that the "magic" cable with all of its various dip-switches does indeed work!  I am running my V10 graphics at 1920x1200 on an Asus PB278Q.

[Image: i2EGH9s.png]

Octane2 O2plus O2 
pcar
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05-05-2019, 12:27 AM


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