Xenium/OpenXenium Xblast for 128MB RAM Upgrade

[mjkthirdeye]

Inspired by a suggestion from Jade on the Xbox-Scene discord regarding a way to make Xenium modchips compatible for use with XblastOS for the purpose of testing RAM during 128MB upgrade installs, I've arrived at what I consider to be the easiest methods to do so.

This guide assumes that the user has a basic working knowledge of the Xenium modchip and its functions as well as access to tools that exist to maintain them, such as Xenium-Tools by Ryzee119, as well as accessing and copying files to the Xbox HDD.
 
The user will also possibly need a secondary way to access the contents of the xbox HDD. This can be done by connecting the drive to a computer and mounting it with Eaton's FatXplorer or by installing the drive into another working hardmodded Xbox.

Unfortunately we cannot use PrometheOS for this process as it depends on the recovery bank being intact, which is not the case with PrometheOS, as that space in the flashrom is used as extra headroom for the OS application itself.

So with that in mind, we'll be using Xenium OS 2.3.1

The way it works is that we need to replace the existing XeniumOS bootloader with XblastOS itself so that the system can boot properly with more/less than 64Mb/128Mb of RAM.

There are a couple ways to go about doing this:
The quickest and most straight forward way to do this is to write the included modified 2MB dump of Xenium OS 2.3.1 to the chip with Ryzee119's Xenium-Tools. After it's done, power off the system, then power on again.

The alternative method is to use a modified recovery.bin to overwrite the Xenium OS bootloader via Recovery mode.
This method requires you to have XeniumOS already installed on the chip.  A copy is included in the download incase you'd prefer to use this method, and aren't currently using XeniumOS, and can be installed with Xenium-Tools.
Simply place the included modified recovery.bin in the root of your Xbox's E:\ partition and either boot the system and select the Recovery option from the XeniumOS menu or physically switch the chip to recovery and then boot the system.

If you aren't familiar with Xenium recovery process, when booted in this mode and a recovery.bin file is found, the front panel LED will flash orange a few times before flashing a sequence that appears to be a FRAG (Flashing Red and Green) while it's writing the recovery data to the flashrom. Note that this is not an actual FRAG and is completely normal. Just wait patiently until the system shuts down on its own. Once it does, the recovery process should be completed.

If you switched the recovery switch on the Xenium chip or bridged the recovery pads on an OpenXenium, be sure to switch back or remove the jumper to return to normal operation before booting up again.

In either case once you have installed the modified image, boot your system and instead of XeniumOS it should now boot to XblastOS!

From this point you can now use XblastOS to test your RAM chips as you install them. You can also perform any of the other useful tests and functions available within Xblast. You cannot, however, use Xblast to flash your chip back to a normal functioning state. Xblast just isn't written with the functionality to do this for these chips. In fact it won't let you flash the chip at all, and this is actually a great thing in my opinion. It eliminates the possibility of accidentally bricking the chip.

So now you've got your RAM installed and you're ready to return your Xenium to its normal functioning state. Now what? Simple! We just use the recovery mode along with the original non-modified recovery.bin to restore XeniumOS to the chip. From there you can use it as normal to flash a BIOS, and resume normal use. You can then use Xenium-Tools to upgrade or return to PrometheOS.

 

Of course, these methods are just two of the more "basic" ways to accomplish this without the need for external or alternative means to program your modchip.
You could also just use an external programmer to write the modified dump to the chip and then subsequently write whatever desired dump to the chip afterwards, or even use an extra modchip to boot the system to then hotswap and write a new dump to the Xenium with Xenium-Tools.

So now that we know how it works and how to do it, allow me condense it down into a few bullet points and notes for an experienced user's tl;dr:

Files included:
XeniumOS-2.3.1.bin - Original non-modified copy of 2MB XeniumOS 2.3.1 flash dump
recovery-2.3.1.bin - Original non-modified copy of XeniumOS 2.3.1 recovery.bin
Xenium-XblastOS.bin - Modified XeniumOS 2.3.1 2MB flash dump -- Replaces XeniumOS bootloader with XblastOS
recovery-xblast.bin - Modified XeniumOS 2.3.1 recovery.bin -- Installs XblastOS over XeniumOS bootloader. Used the same way as original recovery.bin

Main method - Modified Xenium 2.3.1 2MB dump
- Boot the system
- Rename "recovery-2.3.1.bin" to "recovery.bin" and copy it to the root of Xbox E:\ partition
- Copy "Xenium-XblastOS.bin" to your Xenium-Tools folder 
- Use Xenium-Tools to write the modified dump to the chip
- Xblast is now installed!
- Use XblastOS to test RAM installation
- To return to normal operation: Use Xenium recovery mode process to restore XeniumOS and normal functionality

Alternative method - Modified recovery.bin - MUST HAVE XeniumOS INSTALLED ON CHIP TO USE THIS METHOD
- Boot the system
- Rename "recovery-xblast.bin" to "recovery.bin" and copy it to the root of Xbox E:\ partition
- Reboot system and select Recovery at XeniumOS menu.
- Wait for system to shut itself down
- Xblast is now installed!
- Use XblastOS to test RAM installation
--- To return to normal operation:
- Remove HDD and connect it to PC or another modified Xbox to access files
- Remove or rename file E:\recovery.bin. Name it something else, such as "recovery-xblast.bin"
- Rename "recovery-2.3.1.bin" to "recovery.bin" and copy it to the root of Xbox E:\ partition
- Reinstall HDD to Xbox
- Use Xenium recovery mode process to restore XeniumOS and normal functionality

 

Hopefully some of you may find this useful for your future RAM upgrades endeavors!

Cheers!

 

Xenium-Xblast-Install.zip

Edited October 14 by mjkthirdeye
Fixed formatting and added some extra info.

[Spirit of Death]

Why so complicated and with the chance of bricking the modchip? 

1. Copy XBlast.bin and Cerbios.bin (Or any other bios you like to have back on your TSOP) to C:\bios\....
2. Flash XBlast.bin to the TSOP.
3. Do your Ram upgrade. 
4. Flash back the TSOP with Cerbios.bin (Or any other bios you like to have back on your TSOP) using the Update XblastOS option. *

* Alternative use FTP flash.

That way you didn't end up with a may bricked console and chip if something goes wrong.

[mjkthirdeye]

I agree that this is far from the most efficient way to do this.
Still, people have asked for the ability to use a Xenium to test RAM during the upgrade for a long time and the answer has always been along the lines of it's not possible, when really it is - albeit with a bit of a workaround.

So I just decided to make it a viable option for those who wish to.  Besides, the chances of bricking your chip this way are actually pretty slim. No more so than flashing PrometheOS, and not much more than bricking your TSOP with a corrupted flash. Also in comparison to recovering from a bad TSOP flash, fixing a corrupted Xenium is somewhat less of a chore.