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[EvilWays]

I'm actually working on this, but all I have is a Matrix modchip (meaning I can't run a VGA debug BIOS) until hopefully next week. I'll try to get more details made available (and will be a part of spillage's tut of a shitload of connectors on the back of the Xbox), but the basics of it is pin 35 goes to pin 1 of a 74HC14 chip, pin 2 going to one of the sync pins on the VGA adapter, pin 36 goes to pin 3 of the 74HC14 chip, pin 4 to the other sync pin of the adapter, pin 7 of the 74HC14 chip to ground and supply 1.5V to pin 14 (available from pin 40 of the Conexant chip).

What I'm working on is using alternative points (vias) so that nothing has to be soldered to the chip (creating possible shorts.

[EvilWays]

The 74HC14 is a DIP chip that contains Schmitt Triggers. Just wire and go...

[Nedder]

Is it possible to make a 256kb VGA bios? I have a v1.5 with 256kb so I have no way to use the Pixel8 bios.

[bibi]

Nedder : read above, Phoenix bios loader is your friend.  

I must add that the vga bios is only compatible with xbox v1 and v1.1.

[EvilWays]

Why bother? Besides, I already have a SmartXX pre-ordered (why do with software what can be done with hardware?)...and no, there is no 256KB VGA BIOS...it's somehow interwoven into the debug BIOS.

[bibi]

QUOTE

that makes no sense.. all xbox 1.0 and 1.1 have 1mb bios so u can use the bios on the tsop. the bios only works on 1.0 and 1.1 xbox's so why use the bios loader?

Have you ever think of people who deosn't want to mess with the tsop, clever guy ? The bios loader is just as easy to load as XBMC or an emulator.

[EvilWays]

Anyways...

This is approximately what the setup looks like. I'll get into more details when I get my new modchip, and when I get my hands on a better digital camera (mine sux ass).

Just to let you know ahead of time, I've (hopefully) identified alternate points to solder to so that no soldering wires to the chip would be necessary (which is why I need a better digicam to identify said points).

[EvilWays]

The camera saves the pix as JPEG, but in the equivalent of adobe photoshop's quality level 1 (maybe 2), and can't take closeup pixs at all.

The points I found are on the under side of the board. They're at 4N. Look for C4N3, then in the "upper left corner" (with the AVIP and network adapter facing up), there will be two vias and 4 solder pads (one via is just above the C4N3 marking). The two vias are the points for pins 35 and 36. I havent' found a good point to use for pin 40 yet.

I haven't tested this yet, and I didn't want to mention the points just yet since I haven't verified those are the points needed. And what I'm gonna end up doing (for myself) is put that chip plus an LM1881 chip on the same breadboard and control which one is active by a DP-3Pos switch (center pos for SoG capability, one side for LM1881, the other for 74HC14). This is for me to test compatibility with monitors at various friend's houses so that if they want the setup, I can tell them what they'd need.

*EDIT* One more thing...I can only verify those points on a v1.0 box. I have another mobo, but I'm unable to identify as to whether it's a v1.2 or 1.3. The only thing I have to go on is:

1. On the V1.0, there's a cap on C2N2, but not on the other board. Plus, that and C2N1 are black, while C2N1 is mustard colored.
2. U2T1 is SC1186CSW on the v1.0, but there's a smaller chip on the other (SC2688S)
3. C4P19 is black on my v1.0, and mustard on the other.
4. The crystal about 1/2" right of the IDE connector is labeled R270ABC1 on the v1.0 and labeled TXC 27.0Y5NF on the other.
5. Conexant chip has 0202 marking next to Philippines on the 1.0, and 0249 on the other (I assume this is a work date (as in 2nd week of 2002, and 49th week of 2002 respectively)

I have no case to use the Version Identification Tutorial, so that won't work. If anyone could help me ID this board, that'd help me a lot.

[EvilWays]

I guess that's all fine and dandy if you want to make it permanent, but not everyone wants it permanent.

I still haven't ID'd the board I have yet (but I should be able to fire it up (finally) today after I replace a big capacitor I broke), but I've found alternate soldering points underneath the board just "south" of R4N13 (they're two vias with a decent amount of solder on them.

The idea I'm shooting for is modularity. That way, if the mobo dies, you just desolder some wiring and maybe salvage the RAM off the dead mobo.

I was confused by when you said

QUOTE

If you place it near C3N3 you can connect pin 8 (1,5V)...

...referring to the diagram I made, 1.5V goes to pin 14 of the 74HC14, as pin 8 is the input for trigger #4.

If I can, I'll try to get this done, but I won't guarantee a tut...and I have a lot to do before I can start on this.

[EvilWays]

At least I can use them for RAM upgrades.

Gotta find me a v1.1 board...and another pin header (soldered the one I had to the board and now it doesn't wanna desolder) since I assumed I could get this board up and going without problems. I still don't know what version this (now dead) board is...

[Pandoriaantje]

i've got an incomming xbcase and am thinking of doing the VGA mod too, as the case has holes for it and it seems easy for LAN party's.

i'm using the xbcase manual (i've put it up @ http://members.lycos...xbox_einbau.pdf)

first, thx to diNgdoNg for the alternative encoder solder points.

i've got one question though, if i did the mod can i still use the normal AV/out?
if not, where do i put a switch?

[Pandoriaantje]

[Pandoriaantje]

QUOTE (diNgdoNg @ Apr 7 2004, 12:48 PM)

... The only reason I can think of where you would need to install a switch is, if you intend to build an internal VGA connector to avoid having to use special VGA cables. In this case you would install a dip-switch to the backside of the xbox to be able to set VGA (and other video modes) manually. ...

that's exactly what i'm gonna do (as you can see in the xbcase manual) because the xbcase provides a hole for the connector , so a switch will be needed then..

the thing is, the manual doesn't speak of any switch...  

[spillage]

It has been suggested by respected members of this community that on a typical display device you can't tell the difference between geniune VGA and transcoded. If transcoding is done well it should be amazing. The X2VGA is a great tool, plus it has the benefit of the analogue and digital o/ps as well. The benefits are really there for anyone is going to try a full back panel mod like I have and am currently re-doing. My new case as the VGA unit mounted on the back panel with 5 BNCs wired to the pcb to give me RGBHV on an alternative connector. It also has the benefit of being neat and self contained. The X2VGA also provides VGA immediately rather than having load up game saves before getting a decent image.

The internal method is certainly a good mod and I look forward to reading the results of what you guys are doing especially EvilWays who is working hard for the benefit of all with a multi sync comparator.

I completed this image earler for use in my tut but I am certain someone can make good use of it now. Any errors would be gratefully received, either post or PM me.

[Pandoriaantje]

QUOTE

If you place it near C3N3 you can connect pin 8 (1,5V) directly to the 'putting green' (scratch and solder)

so you are saying to scratch the green layer to solder to it?
but  using my (ananlogue) multimeter i come to the conclusion that the left side of C3N3 (resistor?) is connected and reading 0 Ohm. So wouldn't it be possible to just solder to C3N3 instead of removing the green layer?