Xbox 360:RGH/EXT CLK

EXT_CLK is a modern RGH method by Octal450 that uses the EXT_CLK_EN point instead of CPU_PLL_BYPASS to allow reliable glitching of Xenon and Zephyr Xbox 360 consoles.

Equipment Needed

 * A glitch chip:
 * It is highly recommended to use STBY_CLK instead of a built in oscillator with EXT_CLK, but if you wish to install a crystal on a glitch chip it's best to use a 48 MHz one.
 * Coolrunner Rev A/B/C/D
 * Matrix Glitcher
 * X360ACE V1/V2/V3
 * A PC running Windows Vista or later
 * A soldering iron, solder, and flux (MG 835 recommended)
 * Isopropyl alcohol (91% or higher recommended) and cotton swabs
 * A NAND & Glitch Chip Programmer:
 * xFlasher 360
 * NAND-X
 * JR-Programmer
 * Matrix Flasher
 * J-Runner with Extras (Includes EXT_CLK Matrix/Coolrunner Timings)
 * EXT_CLK Timing Files (X360ACE chips only)

Motherboard Points
The points you need to solder to are similar to RGH 1.2, aside from using EXT_CLK instead of PLL.
 * 3.3v
 * 1.8V (Only if using an X360ACE)
 * Xenon
 * Non-Xenon
 * EXT_CLK
 * STBY_CLK
 * Top (Xenon)
 * Top (Non-Xenon, either boxed point works)
 * Bottom (Non-Xenon)
 * POST
 * Bottom
 * Top (requires scraping)
 * CPU_RST
 * C7R112
 * On Xenon, these pads have a capacitor installed. The capacitor will need to be removed.
 * R8C2
 * GND
 * Near 3.3v (clean installation)
 * AV Port (A bit easier to solder)

Matrix

 * A - RST
 * B - POST
 * C - STBY_CLK (remove oscillator if equipped)
 * F - EXT_CLK
 * If you have a Matrix that comes with an oscillator, it can be easily disabled if this resistor is removed instead of removing the entire oscillator.

Coolrunner

 * A - EXT_CLK
 * B - STBY_CLK (remove oscillator if equipped)
 * C - POST
 * D - RST

X360ACE (V1/V2/V3), DGX

 * C - POST
 * D - RST
 * F - EXT_CLK (22K ohm resistor required)
 * Remember to remove the diode and connect 1.8V

Programming the Glitch Chip

 * 1) Plug the cable from your programmer into the chip programmer.
 * 2) * If you are using an xFlasher, ensure the switch is set to.
 * 3) * CoolRunner: Slide switch to "PRG".
 * 4) Open J-Runner with Extras. Click "Program Timing File" in the upper left and select your console’s tab and the relevant radio button for EXT_CLK.
 * 5) * You can use the timing assistant in the bottom left to auto select a safe timing for your motherboard revision.
 * 6) Click "Program". When complete, unplug the cable from the glitch chip.
 * 7) * Coolrunner: Set the switch back to "NOR".

Decrypting the NAND

 * 1) Connect Ethernet and power on the console. The Coolrunner should blink once or more times, and then the console should start into XeLL RELOADED.
 * 2) Once XeLL finishes, it will display your CPU key and some other info. There is also an IP address.
 * 3) Enter the IP address into the box on the lower right of J-Runner and click "Get CPU Key". J-Runner will pull the info from the box, and decrypt the NANDs automatically.

Writing New NAND Image

 * 1) Power down the console, and connect your programmer to the motherboard.
 * 2) * If you are using an xFlasher, ensure the switch is set to.
 * 3) In the upper right of J-Runner, ensure the   radio button is selected.
 * 4) * For Non-Xenon boards, select SMC+
 * 5) Click "Create XeBuild Image". This will take a few moments.
 * 6) Click "Write NAND".
 * 7) Disconnect your programmer when the process completes.
 * 8) Boot the console several times and ensure it boots consistently. If not, make sure your wiring is clean and neat and avoids noisy area. Run the wires near the X-Clamps for best results.
 * 9) Tune glitch chip timings if necessary.
 * 10) Return to the RGH main page and continue in the Cleaning Up section.

Tuning Boot Times
If the light stays on at the end of a cycle: - This means that the checks were passed, but the console failed to start - Probably the timing is too low, or the pulse length is too large

If the light goes off at the end of a cycle but doesn't boot: - This means that the checks failed - Probably the timing is too high, or the pulse length is too small

Note that the debug light behavior may be slightly misleading due to using POST_OUT bit 0.