My Xbox modification project : A worklog and reference for future modders.

Discussion in 'Modding and Hacking - Consoles and Electronics' started by bennydiamond, Feb 8, 2013.

  1. bennydiamond

    bennydiamond Gutsy Member

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    Hello there, I am currently modding an Xbox and I thought it could be instructive to some people to provide a work log of my work. I also post this to spark interest and maybe collect suggestion and ideas for my project.

    Here are the predefined parameters of my construct:
    Base system
    -Original Xbox v1.2 motherboard
    -Replaced thermal compound on CPU and GPU as it's getting old
    -Standard black case
    -Standard Delta power supply
    -Samsung 605b DVD drive
    -Replaced laser unit with one from a 616T that had a dead motor​

    Modification planned
    -Install Xecuter 3 CE modchip
    -Install X3 pro switch
    -HD44780 LCD connected on X3 chip
    -Bigger Hard drive
    -500GB IDE or bigger SATA along with converter, I haven't decided yet. ​
    I already have the 500GB but I think this mod could deserve a bigger HDD.​
    -128MB RAM mod
    -Integrated VGA port with internal H-Sync and V-Sync signals (no LM1881)
    -With switch to toggle Mode 1+3, Mode 2+3 or nothing to still be able to ​
    use standard Xbox video cables​
    -Integrated TOSLINK audio port
    -Integrated 3.5mm audio jack for analog audio
    -XERC 2 mod to turn Xbox on from IR Remote
    -Custom PCB I made and programmed using code on www.sickmods.net
    -IR eye mounted on front panel to provide wide angle detection
    -Integrated MS DVD dongle
    -Mapped to controller port 4 with a relay​
    -Using IR eye from XERC 2 mod​
    -Wired through a USB hub to supply multiple USB ports​
    -Mount 2 USB ports under the front panel
    -Wired through the USB hub​
    -Mounted sideways, one on each end of the faceplate.​
    -Replace stock fan with 80mm blue LEDs fan
    -Blue/Red LEDs on eject button light ring
    -Translucent Stock jewel with blue LEDs mod
    -Blue LEDs in vent holes and controller ports
    -Under controller ports​
    -Side vents​
    -LEDs are powered by an External 5V power supply​
    -LEDs are toggled with a FET transistor wired to an internal 5V source.​
    I don't want to overuse the internal power supply as it will already supply​
    extra current to the extra RAM chips, XERC 2, MS DVD dongle, relay,
    USB hub and probable USB devices (IpazzPort for XBMC?)

    And after that I think it will be enough. Any other suggestion for mods?

    I already have all the parts I need, minus a bigger hard drive if I was to decide to install a 1TB or 2TB.

    What's done so far
    -Blue/Red LEDs on eject button light ring
    Easy mod here, nothing to say except I bought the leds from eBay as Digikey was out.


    -X3 chip installed
    I used a standard pinheader modchip install. Since I did not have a X3LCD I had to use the small solder pads near the LCD connector on the X3 chip. These were are a pain to solder onto.... I finally managed to correctly solder all the wires I needed and then I sealed everything in hot glue. I used some 30AWG wire that I stripped tinned before soldering them. The best way I could find to solder them was to put all wires in row on a piece of kapton tape. With the kapton tape, I was able to place the wires to exactly match the solder pads and solder them all at once without risking touching another solder pad by mistake. Initially I had this trouble and I did not manage to solder all the wires without bridging solderpads or disconnecting the wires. You can see on the picture that in my multiple attempts and frustrations that I accidentally hit the contrast potentiometer plastic wheel on the chip with my soldering pen... It's still working fine.
    [​IMG]



    -HD44780 LCD mounted on front panel
    I bought a special HD44780 LCD screen which is mounted on a smaller than usual PCB and uses flat cable. It is a TC2004b made from Vatronix. It is perfect to mount on an Xbox front panel. Most generic HD44780 LCD are mounted on a PCB that will not fit on a front panel without removing controller ports 3 and 4. This particular LCD does not make use of the contrast potentiometer on the X3 Chip, I only needed to solder 15 wires on the X3 wire instead of the usual 16. The wires goes to a flat cable connector for easy interface.

    Cutting the front panel was easy. I started with a rough cut using a dremel and finished with a metal file. The hole was precise enough so that the LCD would fit perfectly and stay there without any adhesive. Still I added a little bit of hot glue around to secure it. Unfortunately I went too far with the dremel on the top left corner and made a small cut. It's not that big and I'll probably end up making a small hole and install a led over it that will blink when IR commands will be received. Not sure if it's worth the trouble as it is not really visible from a reasonable distance.
    [​IMG]


    -XERC 2 IR eye mounted on front panel
    I installed it just on the left of the LCD. I made a small groove on the opening of the LCD screen. It will be wired to the XERC 2 with a 3 pin connector.
    [​IMG]


    -Thermal compound changed


    -128MB RAM mod done
    Nothing special here except it is a tricky mod. I salvaged the RAM chips from a defective 1.0 motherboard using the hot air gun of my 852D+ solder rework sation. Easily done without any bent pins, just make sure you don't heat too much to damage the chips. I then proceeded to clean the pins of excess solder. Flux on the solder pads of the 1.2 motherboard, I proceeded to solder two pins to secure the alignement of the chip. Soldered all the pins. I the proceeded to check every single pins of the 4 new chips for short circuits. Some pins are bridged by default.

    For the records, the date codes of the 1.0 and 1.2 RAM chips are different but they still work great together.


    -XERC 2 PCB mounted underneath the motherboard
    This is a custom PCB I designed following the design schematic of the original XERC 2. The creator of this project provided the community with all info to create your own XERC2 so I did as he was not selling it anymore. Here is the website with all the info: http://diy.sickmods.net/Our_Products/XERC_2/About/. I had the PCB made by SeeedStudio and their Fusion PCB service, I couldn't only make one so I had 40 little PCB made. These are single sided 0,8mm thick PCB without any copper on the bottom side so you can mount them directly on the motherboard without any risk of electrical contact. I will put them on sale here if people want them.
    [​IMG]

    The system has been tested and boots fine through IR remote, temperature are good and extra RAM is recognized

    What's currently being done
    I drilled the holes in the controller ports and mounted the LEDs onto them. Easy but I still removed the metal shielding of one of the port just to be sure where to drill to not mess up the connections or conflict when a controller is inserted. The best positions are on the edge of the metal shielding on the opposite side of the black plastic bar. Once the leds are in place and soldered 2 by 2, I put some hot glue to isolate them.
    [​IMG]
    IMAG0606
    I will then mount them back to the case and wire the LEDs togheter. These will be ready to wire them once the motherboard is back in place. They will be connected with the LEDs in the vent holes under the faceplate.


    I also placed the relay upside down near the controller ports 3 and 4 connector on the motherboard. I wired the D+ and D- signals (green and white wires) on solder points directly on the motherboard to the common terminals of the relay. The coil of the relay needs 12V to activate. I found a solder point near a capacitor that supply me with such voltage. Don't forget to install a diode in inverted position to dissipate any built up current when the relay is turned off or else you'll get nasty results (black band, or cathode goes on the 12V side).
    [​IMG]

    The idea of this mod is simple. By breaking the 3 metal tabs around the fourth controller port on the metal casing, you isolate the metal shielding of the controller port. You connect the other pin of the coil of the relay to the shielding of this controller port. This way there is no current flowing in the coil and the relay is OFF. As soon as you plug a controller, the ground is restored to the controller port's shield and the coil activates, switching the relay from OFF to ON. This mod make sure the MS DVD dongle is connected to the fourth controller port by default. As soon as a controller is plugged in the same controller port, the relay will switch on, severing the data connection of the MS dongle (and USB hub in my case) and connecting the data lines of the controller.

    After that, I will wire the USB hub to this relay. The USB Hub will provide connection to the MS DVD dongle and the 2 extra USB ports.


    I also mounted the DC barrel jack for the external power supply. I thought I should avoid putting it near the A/V connector as it will be populated by a lot of new stuff for VGA and audio. I decided to mount it just over the main power connector. I drilled a hole through both the plastic and metal casing. I then widened the hole on the plastic case to mount the barrel connector on the metal casing. This power connector will be used to supply power to the LEDs switched by the MOSFET switching circuit.
    [​IMG]
    I had little space to work so mounting the barrel connector where I wanted forced me to slightly trim the plastic around the main power connector on the Xbox power supply itself.
    [​IMG]


    While I was trimming stuff, I took the time to trim the replacement 80mm fan for it to fit in the case.
    [​IMG]

    What's left
    -I should test if the current mods are working well before installing new stuff.

    -All the video stuff. Finding all signals that are available topside of the motherboard. VGA signals and implement a TTL level converter circuit for the internal H-Sync and V-Sync (from 1.5V to 5V to be VGA compliant). I also need to find solder points for digital and analog audio and mode switching to enable VGA.

    -I will also need to cut holes in the plastic and metal casing for the new VGA, audio ports and mode switch.

    -Install the new fan

    - Finish installing the blue LEDs everywhere.

    That should be it. I will try to put links to all my reference on the internet. Most of them are on Xbox-scene forums.

    Reference for mods

    VGA connectivity:
    Video modes for VGA output selection:
    http://forums.xbox-scene.com/index.php?showtopic=213487

    A good chart for mode selection truth table:
    http://www.gamesx.com/avpinouts/xbox.htm

    Mod idea for voltage level conversion of H-Sync and V-Sync, good in practice but I prefer getting a true 5V TTL signal instead of 2.65V in case I hook up a picky VGA screen:
    http://forums.xbox-scene.com/index.php?showtopic=624248

    General VGA How-To from Xbox-Linux (on archive) (be advised that the pictures on where to get internal sync signals on vias probably are for 1.0/1.1 motherboards as they were not at the same place on my 1.2 motherboard):
    http://www.xbox-linux.org/Xbox_VGA_HOWTO
     
    Last edited: Feb 8, 2013
    Daniel270176 likes this.
  2. HEX1GON

    HEX1GON FREEZE! Scumbag

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    Good luck with the mod, however correct location would be in a the mod section :)

    Only suggestion I have is to paint the case, I think no mod is complete with a change of colour or finish.
     
  3. ASSEMbler

    ASSEMbler Administrator Staff Member

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    Either section seems appropriate, I will mirror it.
     
  4. HEX1GON

    HEX1GON FREEZE! Scumbag

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    Ah sorry my mistake, this just seemed more of a mod project than a discussion. I'll remember that next time.
     
  5. weinerschnitzel

    weinerschnitzel Spirited Member

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    I also want to install a true vga output without using the LM1881. A nice guide for this would be awesome! I'd even pay you to build me the circuit if you could swing it.
     
  6. sonicdude10

    sonicdude10 Insane redneck retro gamer...

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    I've wondered that myself since the pin-out diagram for A/V port has the H and V SYNC labeled on there but is disabled due to the GPU putting out component for NTSC and RGB for PAL (I think...) video modes. Maybe the VGA BIOS enables them? They use the same 3 lines for component, RGB, and VGA depending on region, BIOS, and signal pins connected.
     
  7. bennydiamond

    bennydiamond Gutsy Member

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    Well first of all I am not equipped at all to do any kind of paint job on plastic, nor do I have the experience.

    Second of all, I prefer to leave the casing as close a possible to the original. All the console mods I did uses the original case (except for my GameCube for which I have an Xecuter Case to put regular sized DVD-R) in order to make apparent the mods I did to enhance the functionnality.


    I will be sure to detail this section of the modification as I understand that the modders on these forums really enjoy mods that enhance audio and video quality.

    The circuit I plan to use isn't really sofisticated. 4 NPN transistors (2N3904 or 2N2222 will do) and a couple of 1K ohms resistances will suffice. The hardest part is to solder to the tiny solder points on the motherboard. I will provide will pictures and comments when I'll be doing it.

    I'm not at home right now so I'll try to search and find the references I used and post them in the top post.


    The standard sync signals for VGA (H-Sync and V-Sync) are not present on the A/V port of the Xbox since it was not initially plan to output VGA natively. However these are present between the GPU(As it is essentially a Geforce 3 PC GPU) and the video encoder. The video encoder take these and encodes them in either YCbCr for component, RGB for SCART, Luma and Chroma for S-Video or composite.

    What the VGA bios does is that it instruct the video encoder (Conexant or Focus) to output RGB signals directly instead of the YCbCr encoding normally done for component output. Essentially, the VGA bios will overide the normal operating mode when component video is selected (mode 2+3). YCbCr isn't anything like RGB in terms of signal shape and wouldn't work at all with a true VGA output.

    I think that mode 1+3 VGA is natively possible with any bios but it won't enable digital audio output. Also some game will have video encoder settings pre-encoded which could result giving the image a greenish tint . The VGA bios will instruct the system to ignore these hardcoded settings and use the bios settings.
     
    Last edited: Feb 8, 2013
  8. bennydiamond

    bennydiamond Gutsy Member

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    Just a quick update here.

    I decided to install the whole IR portion of the mod by hardwiring the MS DVD dongle PCB directly to the motherboard.

    I initially had a populated PCB of an USB2.0 hub and I intended to use it as the hub I planned on installing but I did a quick test and it doesn't get picked up on my computer anymore (tried lsusb command on Lubuntu Linux).

    So just to test that the MS DVD dongle gets identified correctly by the Xbox and also to make sure that IR commands can successfully be received through the IR eye of the XERC 2 mod, I simply wired the D+ and D- (data connections of USB) to the relay. Bypassing the initial requirement of the USB hub. I plan on testing tonight and produce a small video if you want to check how things are working right now.

    Here it goes:
    I stripped a long time ago the dongle's PCB from it's plastic casing and removed the Xbox controller connector from it. I then managed to solder wires for power, USB data and IR input data. I try to follow as much as possible the conventionnal color code of sutff so for USB you'll have the standard Red,Green,White and Black wires. The greyish wire is for the IR data that's coming in from the XERC 2 PCB (essentially it's from the IR eye but it passes through a signal diode).
    [​IMG]

    Initially I wanted to put the dongle's PCB underneath the motherboard to save space but the crystal on it is just way to tall. I had to put it topside or else I could risk shorts circuits.

    Then I prepared the place where the PCB would rest on the main board. I figured that making it sit on 2 RAM chips wasn't a bad idea. Of course this way air circulation on the chips themselves gets blocked but the MS DVD dongle pcb as a really thick ground copper plane (I had to crank up my soldering iron to 500C to solder the GND wire). This way, if properly fixed on the RAM chips, I could use the PCB as some sort of heatsink (not that it really matters, I never noticed the RAM chips on the Xbox getting hot). I have a tube of thermal compound glue which will bond and has a really good heat transfer coefficient. I've put a dab on both chip and a strip of hot glue on the side to secure the MS DVD dongle's PCB in place:
    [​IMG]

    I placed the PCB on top of it and as soon as I pressed on it to secure it, the hot glue solidified right away, proving my theory that the heat of the glue was easily transfered to the copper plane of the dongle's PCB, acting as a heatsink. I didn't even scraped the soldermask (green gunk) off the gounding plane.
    [​IMG]

    The PCB was already solidly in place that way but the heat compound glue will help in this matter as to transfert heat as well. I soldered all the wires in place. Capacitors are great place for power and ground solder points and I try to use them when they are near. Just make sure not to leave your soldering iron for too long when soldering on a ceramic capacitor or you could break the ceramic itself, rendering the capacitor useless.
    [​IMG]

    With this done, I left it there for the heat glue to bond and I will continue on with a test to see if the thing boots off IR and receive commands to control XBMC.
     
  9. bennydiamond

    bennydiamond Gutsy Member

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    Here is the video I said I would make about the testing of the XERC 2 and using the it's IR eye for the MS DVD dongle.

    Turns out I made a small error on my XERC 2 PCB design. I inverted the diode's pins. A simple fix: desolder the diode and a 180 degrees rotation and I was good to go.



    Everything works great. I tried using the remote from about 6-7 meters and it gets 100% picked up everytime, even at a wide angle!

    A big thank you to pablot (creator of the XERC) and Sickmods for the source code and diagrams! I could have made my own but this device is really advanced (much more than X3IR if you ask me). You saved me alot of time! If anyone wants one, I urge you to go over www.sickmods.net and maybe email them to ask if they would produce some. If not I could have some to sell, assembled with IR eye or just the PCB.
     
    Last edited by a moderator: May 25, 2015
  10. sonicdude10

    sonicdude10 Insane redneck retro gamer...

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    Nice. Here I was just going to do the simple Xbox DVD remote power switch mod and be done. Now I'm going to have to do something like this...
     
  11. weinerschnitzel

    weinerschnitzel Spirited Member

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    http://forums.xbox-scene.com/index.php?showtopic=741521

    I read this thread awhile back before considering a VGA mod using internal HSYNC and VSYNC. Apparently the voltages for RGB are too low and need to be amplified for a perfect VGA signal. If you come across something like this, I'm all ears.

    Strangely on my xbox, the LM1881 VGA box I made no longer works, and the Toslink connection I installed failed as well. Component still works for me which is strange, so I ordered an official MS HDAV pack to troubleshoot further.
     
  12. bennydiamond

    bennydiamond Gutsy Member

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    I definitely recommend XERC, you can customize which button on the remote triggers a certain action, it has support for SmartXX modchips (they access the onboard OS with a certain sequence of power button press). On top of that, there is a Led fader on the LED ring (breathing effect) when the console is off that you can turn off if you don't want it.

    PM me if you want more info. I can also supply you with the actual mod.
     
  13. bennydiamond

    bennydiamond Gutsy Member

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    I will check out for the RGB line voltage. I'm about to start with this part, probably this weekend since my girlfriend is working.
     
  14. sonicdude10

    sonicdude10 Insane redneck retro gamer...

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    I'll keep it in mind. If so, I'll see if you can get me the XERC plus the supporting mod chip to make my mod easier. I even have an old Panasonic DVD/ VCR combo remote that should be perfect for use with this.
     
  15. bennydiamond

    bennydiamond Gutsy Member

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    XERC works with any Xbox: modchip, softmod or stock. I might have one or 2 modchip laying around. I do know that I have a X-Chip but you might want to get something a little more simple. This one requires you wire an external USB programmer (supplied with) to flash bios images.

    I have an Aladdin XT 4032 but I can't recall if it has the 1.0-1.5 or 1.6 bios on it. That matters because it's a 256kb flash chip so only one bios can fit on it. You can probably find a source that still have some in stock.

    http://www.aliexpress.com/item/free-shipping-Duo-x3-for-x-b-o-x-ic/736161188.html

    http://www.eurasia.nu/shop/product_info.php?products_id=266

    http://www.nh-game.com/category.php?id=63
    I don't know the reputation of the third link but here it is anyway. Others are OK.

    P.S.: You might want to try and flash the TSOP instead of a modchip(if you have an 1.0-1.5 Xbox). You won't get any benefit by having a 256kb modchip
    over a TSOP flash. If you were to screw up your TSOP, then you could go for a modchip to repair it.
     
  16. sonicdude10

    sonicdude10 Insane redneck retro gamer...

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    I was thinking of those chips that have a video out port for using a small composite video LCD for information like HDD space, RAM, temps, ect. I have a cheap Chinese 3.5" LCD I can use for that.
     
  17. bennydiamond

    bennydiamond Gutsy Member

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    Those are hard to find nowadays. most modchips still available in shops are basic mods.
    Here are some chips that support LCD.

    Xecuter 3 (and CE) but as you can read in my top post, it is really hard to solder a LCD that is not an X3LCD(unless you can find the same connector this LCD uses)

    All SmartXX except V1

    Xenium Blue and ICE, I think those only support SPI protocol so you'd need the proper interface chip. I don't know which one but it should fairly easy to get that information. Also maybe other Xenium chips might offer LCD but I don't remember.

    Aladdin XT 4064 some sellers on Alibaba claim they can supply them but in large quantities. Maybe you could contact them for a "sample". Be advised that the 4032 version (most common) doesn't support LCD out.

    LCD-MOD is a device you place between your modchip and your Xbox motherboard with the sole purpose of giving an LCD out port. I don't know if you require a modchip for these or if you can just use this device along with a softmod or a TSOP flash.

    I don't have any spare modchip with LCD out sorry.Good luck finding one.

    EDIT : It looks like my phone's web browser do not play well with the forums... As a result my post looks like p00p... I will fi that when I get home.

    EDIT2: Fixed the text arrangement (or lack of arrangement) due to my old smartphone...
     
    Last edited: Feb 13, 2013
  18. bennydiamond

    bennydiamond Gutsy Member

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    Hello, here's an update on the current situation.

    I've salavged an old USB1.1 HUB to internalize in my Xbox, this is perfect because who needs a USB1.1 HUB nowadays:highly_amused:. So I stripped it of it's plastic casing and desoldered all connectors and USB leads fromt he PCB.

    I then had to solder jumper wires to join the USB connector's sheilding solder points togheter. Poor design from the Chinese manufacturer, the integrity of the ground plane is depending on the sheilding of the USB connectors themselves...

    Anyway, after the jumper wires, I installed right angle pin headers for 3 of the four USB OUT ports for easier interface.
    [​IMG]

    Why is there a USB OUT port that misses a pin header? Because the fourth one will be soldered to the MS DVD Dongle PCB. I mounted the USB HUB PCB on top of the dongle's PCB making sure it wasn't touching anything, not covering any screw holes and that it'll be low profile enough so that the DVD drive plastic tray would still fit in.

    THe way I did it is really simple and ghetto: I proceeded to create 3 hot glue standoffs (the fourth standoff if the crystal on the MS DVD dongle). Easily done, you just put a drop of glue, wait for if to fully cool off, do another one on top of the first and at the third, you place the PCB on them to secure it there. Works like a charm and it makes sure that there is no short possible. It will even keep an airflow for the RAM chips underneath it.
    [​IMG]
    You can see the direct connections from the USB hub to the dongle's USB points, after soldering the power wires. I did a quick test to see if everything was still working.... And it does! Power ON from IR remote and controlling XBMC also works proving that the MS DVD dongle is still getting picked up by the controller port!

    I have to go for now but I will continue with the most important mod of all! I'll leave you a picture below that will probably give you a good idea what it is.
    [​IMG]
    (hint: check the measurements at the bottom)
     
    Last edited: Feb 27, 2013
  19. bennydiamond

    bennydiamond Gutsy Member

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    So VGA out, I hope this will help alot of people to try and make it happen on their own console!

    So following the documentation I linked in first post I proceeded to solder all the wires I would need to get VGA out, Digital and analog audio out. Easily down, just take a multimeter and find points on the top side that are electrically the same from the A/V port(bottom side). The only point I could find a match for topside is digital audio out.

    So here are the R,G and B signals:
    [​IMG]
    Since these are sensible signals I individually twisted a grounded wire to each color wire. Make sure you chose a ground point near the whole video section.


    On the next picture are the 3 wires of the 3 modes selection pins in the A/V connector to select the different video modes:
    [​IMG]
    So the 3 signals are connected to those 3 capacitors on the top side. You can get VGA out with 2 different modes, 1+3 and 2+3. I wired them all three just for compatibility purpose. I bought a small ON-OFF-ON DPDT switch so I could toggle between the 2 VGA modes and none to still be able to use a regular Xbox video cable. The fourth cable coming from the other side of the board is the digital audio signal wire. The bigger red wire is the power (5V) to the Sync signal level-converter PCB (if you use this point make sure you use the same side of the resistor I did. It's a low resistance so you could mess things up if you use the wrong side).

    Here is a good point to tap onto the digital audio signal trace. Unfortunately it is not possible to get the signal from the top board:
    [​IMG]
    See where I passed the wire to get it topside of the motherboard? Perfect place!!

    Now for the internal sync signals. These are going from the GPU to the video encoder. There are screenshot to identify the points elsewhere on the web but they aren't for a 1.2 Xbox for sure!. Here where are mine:
    [​IMG]

    Here's another angle:
    [​IMG]

    Here's the whole thing with the small PCB I made to convert 1.5V signals to standard VGA 5V signals:
    [​IMG]

    This is a really simple circuit:
    [​IMG]
    -The 4 transistors are 2N3904 (could be any small signals NPN like 2N2222)
    -The 6 resistors are 1k ohms (R1 and R4 are the through-hole ones while R2,R3,R5,R6 are 0805 surface mount chip resistors).

    You could use resistors from 1K ohms to 10K ohms, as long as they are all the same value. I wouldn't go under 1K ohm because it'll draw too much current from the Sync signals on the motherboard and I wouldn't go over 10K ohms so the converted sync signals get some milli-Amperes so they won't get cut off by the impedance of the VGA monitor.(is it the proper way to say it???)

    -I used a piece of stripboard that is 4 rows of 8 points.

    Only 3 PCB cuts on the PCB are necessary. This is the most effective design I could come up with that both saved space and retained enough consistency to produce an acceptable result. For this I had to solder all the surface mount resistors on the copper side of the PCB. I don't have an acutal picture of the 4 surface mounts resistors soldered but I have made a graphical representation of the PCB population. Hope this helps:
    [​IMG]


    Just to make sure the theory behind this was solid I quickly reassembled the motherboard and probed the V-sync signals to check if the conversion circuit from 1.5V signals to 5V TTL was working:
    [​IMG]

    It works great! You can notice at the bottom that the measurements indicates a 1.52V peak to peak signal voltage for the input (original Xbox signal), a 5.20V peak to peak signals coming out of the conversion circuit and a frequency of 59,81Hz. This is normal because at those low frequencies, the oscilloscope can have a hard time calculating the frequency so it gives an estimate. Same thing for the voltage level (it's 5,20V and not 5V). This is also due to fact that the signals are floating and not connected to any load. They should go down a little under 5V once connected to a VGA monitor. And if not, it's not big deal, any VGA monitor will tolerate a 0,20V over the specified voltage.

    So now I need to make the holes in the casing to mount the following:
    VGA port
    TOSLINK audio port
    3.5mm audio jack
    DPDT switch (for mode A/V mode selection)

    Then I'll add a few LEDs, change the fan and install a big HDD.
     
  20. l_oliveira

    l_oliveira Officer at Arms

    Joined:
    Nov 24, 2007
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    Great project ! But out of curiosity, what is the point of the relay on the USB ports ?

    You tried to just daisy chain the controllers with the HUB ? There's a HIGH chance it will work just fine without the relay.
     

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