The collected works of michaelpastras

Because I have seen *SO VERY MANY* Posts concerning Sync On Green Troubleshooting and SGI/SUN 13W3 to VGA Adapter Compatibility,
I went ahead and made my very own Adapter that will work *OUT OF THE BOX* with Indy or newer SGI Machine that has 13W3 GFX Output, and with ALL VGA Monitors !!
(Have not tested this with Indigo1 or older, cause I do not currently own one...)

You will not need Sync On Green Compatible/Tolerant/etc.. monitor.
It just works will *ALL* VGA monitors AND with all KVMs!!! Period!

I know they sell SGI and SUN 13w3 to VGA adapters on eBay.
Truth is, **NONE** of them is properly wired to work with SGI!!

A VGA Monitor, in order to display sth properly, it does require : Red (and Red Ground), Green (and Green Ground), Blue (and Blue Ground),
Horizontal Sync, Vertical Sync and Sync Ground (Common Ground for Horizontal and Vertical Sync).
But!! That is not all!
To properly do it, you need to use all the pins a normal DCC VGA monitor uses.
And by DCC, we mean all modern VGAs (TVs, PC Displays, KVMs).

So, how is it going to be?

First, lets see exactly what the pins do in the 13w3 Receptile:


A1 Inner Pin: RED Analog Carrier
A1 Outer Pin: RED Ground
A2 Inner Pin: GREEN Analog Carrier
A2 Outer Pin: GREEN Ground
A3 Inner Pin: BLUE Analog Carrier
A3 Outer Pin: BLUE Ground
Pin 1: Monitor Device ID bit 3 when not in DDC Mode, but in DDC: SCL = Data Clock
Pin 2: Monitor Device ID bit 0 when not in DDC Mode, but in DDC: SDA = Data Bi-Directional Communication
Pin 3: Composite Sync = Horizontal & Vertical Sync Merged
Pin 4: Horizontal Sync
Pin 5: Vertical Sync
Pin 6: Monitor Device ID bit 1 when not in DDC Mode, but in DDC: +5V (This is not used so much...)
Pin 7: Monitor Device ID bit 2 when not in DDC Mode, but in DDC: DDC Ground
Pin 8: Digital Ground (This is different from Analog Ground, cause if you Ground both Analog & Digital Signals together, you might experience Artifacts during Video Playback)
Pin 9: Digital Ground, as well
Pin 10: Sync Ground

Now, the VGA Pins:



When the VGA is operating on "Separate Sync" Mode, the pins are used as such:
(You can also operate a VGA Display on "Composite Sync" or "SyncOnGreen" mode, but we do not care about these right now...)

Pin 1: RED Analog Carrier
Pin 2: GREEN Analog Carrier
Pin 3: BLUE Analog Carrier
Pin 4: Monitor Device ID bit 2
Pin 5: DDC Return
Pin 6: RED Ground
Pin 7: GREEN Ground
Pin 8: BLUE Ground
Pin 9: DDC: +5V (Not used much... - This pin is just missing in many VGA Cables by Default)
Pin 10: Sync Ground OR Monitor Self Raster
Pin 11: Monitor Device ID bit 0
Pin 12: Monitor Device ID bit 1 when not in DDC Mode, but in DDC: SDA = Data Bi-Directional Communication
Pin 13: Horizontal Sync
Pin 14: Vertical Sync
Pin 15: Monitor Device ID bit 3 when not in DDC Mode, but in DDC: SCL = Data Clock

So, there are 2 ways for a computer to communicate with a monitor:
a) By using the Monitor Device ID bits, that tell the GPU details concering: which is the Supported Resolution of the Display, whether it is a Color or Mono Monitor, etc...
and b) Via DDC Communication

All modern Devices use DDC... (TVs, Displays, KVMs)
So, we are going to make an Adapter that works with DDC Monitors.
It is not possible to make an adapter that will work in DDC mode and non-DDC mode in turns.
That is because, for example, in 13w3: the Pin 2, in non-DDC Mode contains the ID bit 0, but in DDC, it contains the SDA
But, in VGA, the Pin 12, that in DDC mode is the SDA, in non-DDC mode, contains the ID bit 1 and not the ID bit 0...

Phew!!

Anyway!!

So Here is what to do:

Connect A1 Inner Pin of the 13w3 Receptile to the Pin 1 of the VGA Receptile
Connect A1 Outer Pin of the 13w3 Receptile to the Pin 6 of the VGA Receptile

Connect A2 Inner Pin of the 13w3 Receptile to the Pin 2 of the VGA Receptile
Connect A2 Outer Pin of the 13w3 Receptile to the Pin 7 of the VGA Receptile

Connect A3 Inner Pin of the 13w3 Receptile to the Pin 3 of the VGA Receptile
Connect A3 Outer Pin of the 13w3 Receptile to the Pin 8 of the VGA Receptile

Connect Pin 1 of the 13w3 Receptile to the Pin 15 of the VGA Receptile

Connect Pin 2 of the 13w3 Receptile to the Pin 12 of the VGA Receptile

Connect Pin 4 of the 13w3 Receptile to the Pin 13 of the VGA Receptile

Connect Pin 5 of the 13w3 Receptile to the Pin 14 of the VGA Receptile

Connect Pin 7 of the 13w3 Receptile to the Pin 5 of the VGA Receptile

Connect Pin 10 of the 13w3 Receptile to the Pin 10 of the VGA Receptile

So, the pins: 3,6,8,9 of the 13w3 Connector are not used, and the pins: 4,9,11 of the VGA Connector will not be used at all!

It is generally a good idea to also connect the 13w3 Chassis to the VGA Chassis.
Just solder a wire on the back of chassis of the 13w3 to the back of the chassis of the VGA Receptile.
(However this is not necessary...)

Also, it is a good idea to use slightly "fatter" wires for the RED, GREEN, BLUE signals and their Grounds, cause they are Analog
Signals and Analog Grounds and we do want them to be relatively secured against Interference, or Signal loss.

Finally, I would suggest to double check that the ends of the wires are not contacting with each other.
Please use "Heat Shrinkable" to secure the contacts, if needed, as I did.

Voila Some Pictures of the Process and the Result!










It does work with the Octane and the Indy out of the box!!!
I checked it with all 3 of my KVMs, my Television, and the SGI F220, which is DEFINITELY NOT a Monitor that Supports Sync on Green!!!
Works!!!

Note that, previously, using 13w3 to VGA "for SGI" adapters, I was getting no video on these devices!
But, with this proper adapter I made, it just works!



In machines with Infinite Reality, like Onyx2, one may have to run terminal and type:
cd /usr/gfx
./setmon -sn 60Hz

That way, you tell the machine to send Separate Sync Data as well as Sync-On-Green Data.
We need this for our setup to work.
There is a possibility you have to do this on The Indy, Octane, etc..., but it is a fact that in my case, my Indy and the Octane worked
out of the box!!

I think that's all!!
Please comment and let me know your thoughts about this!

Cheers from Greece!!!

Indeed!! For these early systems, one does need to have SyncOnGreen Capable monitor!
That is mainly cause they just do not route Separate Sync signals.
In order to do it for them, you need to build a circuit that will separate the Sync Signal from the Green Channel!!
I will show how to do this on a next Guide!

However, I did claim that this Adapter will work on Indy or newer Machines!!

Well! You need:

Female VGA Receptiles. ie: http://www.ebay.com/itm/1pcs-DB15-VGA-F ... 1858515150
(This pack, also has the Cap for the VGA).

You will not find 13w3 Caps, but, DB25 Caps Will Do. ie: http://www.ebay.com/itm/RS232-DB25-25-P ... SwWnFV8suv

Then, you need a cable, which you will have to cut down to several smaller cables to do the job... (You can find such cable in your local shops, I guess).

Finally, for the 13w3 Receptiles, I found the only company that still produces them.
http://www.adamtech.net.cn/product/1923 ... china.html
(Found them on Alibaba/Aliexpress)
Just contact the supplier and make sure you specify which 13w3 receptile you want, cause they do have a lot of different ones...(maybe upload a photo to show them).
And, unless you buy them in BULK (100 or more pieces) it will cost at least 10 USD each one, if you include shipping.

Hope I was helpful.

Mind you, in a month or so, I will start selling them on ebay. (The complete adapters).
So, I can let you know when I am ready and I could sell each one at around 45 USD (and with free, trackable shipping)!