Post by: Master-Chief on August 15, 2004, 09:40:00 PM
I am pretty good at soldering so wiring shouldn't be a problem (unless it's too much, then its not worth it).
Post by: Foe-hammer on August 16, 2004, 02:01:00 AM
Post by: catgut on August 16, 2004, 10:52:00 AM
http://www.x2vga.com
Post by: Master-Chief on August 16, 2004, 11:31:00 AM
Also, I have a Xenium, so BIOS space shouldn't be an issue.
Post by: Master-Chief on August 16, 2004, 08:56:00 PM
Post by: Foe-hammer on August 16, 2004, 09:55:00 PM
Post by: Master-Chief on August 17, 2004, 08:50:00 AM
| QUOTE (DarkLegion @ Aug 17 2004, 09:17 AM) |
| Why don't you do a search instead of expecting everyone to hold your hand? There are several diagrams around with instructions and pinouts,and if you can't figure it out from that you have a lot to learn before trying something like this. |
I did search.
Post by: thecowsays on August 17, 2004, 02:55:00 PM
HERE
Post by: Master-Chief on August 17, 2004, 09:46:00 PM
| QUOTE (thecowsays @ Aug 17 2004, 04:58 PM) |
| jared has an awsome diagram of how to wire up whatever you want HERE |
I have seen that, but it is really confusing how they have all those wires wired to other things and all those switches. Why can't they have just a single VGA port and MVIP Port and show which point is supposed to go to which point.
Post by: catgut on August 18, 2004, 06:31:00 AM
| QUOTE (Master-Chief @ Aug 18 2004, 05:49 AM) |
| I have seen that, but it is really confusing how they have all those wires wired to other things and all those switches. Why can't they have just a single VGA port and MVIP Port and show which point is supposed to go to which point. |
Here's your specific VGA info, MC:
| QUOTE |
| You must first ground pins 11 - 12 and 13 - 14, and enable 480p in the dashboard. Then you remove the ground between 11 - 12, and ground pins 9 - 10, so that you have pins 9 - 10, and 13 - 14 grounded (VGA Mode). You must also have a VGA bios installed. |
and also
| QUOTE |
| unless your monitor/projector supports SOG (sync on green), then you absolutely MUST have the LM1881N chip to separate the sync signals, otherwise you will have no picture period. |
So, let's review:
-open your xbox
-remove motherboard to access back side of AV pin matrix
-solder to specific motherboard points
-make sure that you put switches at the appropriate points so you can switch back to regular composite/svideo modes
-install a sync separator chip (LM1881N)
-modify your BIOS.
Or:
Buy an x2vga.
Post by: Master-Chief on August 18, 2004, 08:24:00 AM
| QUOTE (catgut @ Aug 18 2004, 08:34 AM) |
| Here's your specific VGA info, MC: and also So, let's review: -open your xbox -remove motherboard to access back side of AV pin matrix -solder to specific motherboard points -make sure that you put switches at the appropriate points so you can switch back to regular composite/svideo modes -install a sync separator chip (LM1881N) -modify your BIOS. Or: Buy an x2vga. |
I understand now. Thank's for clearing that up for me man!
Post by: farbird on August 25, 2004, 03:36:00 AM
Post by: EvilWays on August 29, 2004, 02:24:00 AM
MOST IMPORTANTLY...the VGA BIOS will only work (AFAIK) v1.0 and v1.1 mobos. Unless someone manages to get code for the PiXeL8 or TATX VGA BIOSes and can get them to work on the later version mobos, then the first two versions of the mobo are the only ones that the "true" VGA mod will work with.
BTW, X2VGA is a transcoder (and one of the best developed based on word-of-mouth) and not a "true" VGA adapter. The X2VGA uses the Component Video signals (which are @ 15kHz) and ups the frequency to VGA standards (31kHz).
I was working on a project that would make it so that there would be no need for a SoG-capable monitor by tapping into true H/V-sync signals being passed between the encoder chip and the xGPU chip; however, that project is on hold because of the post-graduation/unemployment chaos going on with me right now and not having a working mobo to work with (and photograph for a tutorial).
Post by: DarkLegion on August 31, 2004, 02:49:00 AM
| QUOTE |
| BTW, X2VGA is a transcoder (and one of the best developed based on word-of-mouth) and not a "true" VGA adapter. The X2VGA uses the Component Video signals (which are @ 15kHz) and ups the frequency to VGA standards (31kHz). |
You are wrong here,the x2vga uses the progressive component signals(31khz) rather than 15khz signals although I believe it does some cheap upscanning for the dashboard which can't display in progressive for some odd reason.You could actually build a component to rgb converter pretty easily and cheaply as the sync is the main issue here which is already in 31khz and just needs to be stripped off green.The colour difference to rgb conversion is a pretty simple circuit...not as easy as hacking off the main board and using a vga bios but simple,cheap and far more compatable since it will work with ALL xboxes and it will work with any game that works in 480P and no hex editing hacks will be needed.It will probably work fine in higher res progressive modes too such as 1080i(or whatever particular number it is).I have the circuit on me,but I can't seem to find an attachment option on here so do a google for it,there are a couple of circuits around.The one I have uses MC34182 opamps ,and a slew of resistors...proto board is your friend here.This solution is basically what the x2vga does but without the extra features and thus extra cost
Post by: EvilWays on September 01, 2004, 02:59:00 AM
Post by: EvilWays on October 01, 2004, 07:32:00 PM
Post by: EvilWays on October 02, 2004, 11:40:00 AM
Post by: EvilWays on October 03, 2004, 01:03:00 PM
*UPDATE* It appears that IND-BIOS and Gueux'net groups are addressing this issue.
junkmonkey has hacked one of the IND-BIOS versions with VGA support for the Conexant chip, BUT this is more of a proof-of-concept hack and not official (judging from his post in the BIOS forum, he isn't a member of the group but the group was cool with his hack. Best of luck to him to become an offical member.) and should be considered "beta". This should be available in "The Usual Places".
Yoshi has also posted about adding VGA support in the Gueux'net BIOS. He mentioned v1.4, so if nothing else someone is taking a chance and trying to get the VGA support in Xboxes with the Focus chip. This looks to be a "beta" as well, as Yoshi was looking for people to help test it out since he didn't have a VGA cable.
So, to wrap things up...officially, VGA support is only available for v1.0 and 1.1 boards. Unofficially, work is being done to bring that support all the way up to v1.4, but is still in the test phase. BTW, the size of the BIOSes weren't mentioned.
Post by: EvilWays on October 03, 2004, 08:08:00 PM
| QUOTE (nleahcim @ Oct 3 2004, 11:22 PM) |
| Nothing's even being worked on for 1.6s? |
Too early yet, I guess.
The datasheets are available for the Conexant encoder chip, and I hear digging up datasheets for the Focus chip is a bitch. I don't know if the datasheets for the Xcalibur chip are publicly available or not...if they aren't, then it's all trial and error which makes working on VGA support take that much longer.
Post by: fallafalla on October 04, 2004, 06:23:00 PM
| QUOTE |
| What I was working on (and am still planning to) was to tap the H/V-sync signals off of the video encoder and pass them through the VGA header. The signals would be passed through a 74HC14 Schmitt Trigger to terminate the singal with a 75 ohm load (for monitor safety reasons) and would require wiring six wires to the chip (two inputs, two outputs, Vcc (1.5VDC supplied from the encoder chip in this case) and ground. According to Oliver Schwartz and his article on Xbox-Linux website, this should alleviate the discoloration (I haven't tested this so I can't verify). This also alleviates the need for SoG ready monitors otherwise needed. |
Post by: EvilWays on October 04, 2004, 08:17:00 PM
Tapping H/V-Sync signals passing between the encoder chip and xGPU provides a "pure" sync signal that doesn't require a monitor with SoG capabilities or require sync splitting using the green signal. This should, at least in theory, result in at least less of a green "wash" of color for video.
Post by: EvilWays on October 04, 2004, 10:14:00 PM
I just downloaded the IND-BIOS and Gueux'Net BIOSes and here are the sizes:
iND-BiOS.5001.VGA.b1-junkmonkey.bin - 256KB
Gueux'NeT-VGA-Focus-BFM.bin - 1,024KB
Gueux'NeT-VGA-Focus-Final.bin - 1,024KB
These last two are zipped together.