NOTE: You must have the Epsilon bootloader installed in order to use this update!
* Fixed a bug which made it impossible to remove game saves from XMB
* Compatibility fixes relating to UMD emulation resulting in several previously incompatible games now working, including:
- Blade Dancer: Lineage of Light
- Harry Potter And The Goblet Of Fire
- Sims 2
- Spongebob Squarepants: The Yellow Avenger
- Super Monkeyball Adventure
1) Copy EBUPDATE.BIN to the root directory of your memory stick
2) Enter the Epsilon recovery menu by holding SELECT+START as the PSP is booting
3) Select "Update Epsilon BIOS", then hit X to confirm
We have seen several complaints regarding the UMD emulationcompatibility with Epsilon BIOS. Please keep in mind that Epsilon BIOSis a very new application and as such there may be bugs which need tobe worked out. We aim to improve compatibility and features with everyrelease so please bare with us. We would like to thank whackawookie andother members of MaxConsole forums for compiling the compatibility listand submitting bug reports.This has been very valuable to us - please continue to update the listso we know which games need to be fixed! At the time of writing, gameswhich we are still investigating fixes for include:
- Burnout Legends
- Capcom Classics Collection Remixed
- Ghost in The Shell: Stand Alone Complex
- Splinter Cell: Essentials
- Smackdown VS RAW: 2006
We have also seen some complaints that the EZIP format doesnot achieve as good a compression ratio as other compressed ISOformats. This is due to the compression algorithm used by EZIP, whichdiffers from what is used in the other formats. The algorithm we useachieves *slightly* lower compression ratios but offers VERY fastde-compression on the PSP. Since it takes less time for the PSP todecompress each block of data the games run far more smoothly!
Epsilon BIOS is a custom flash "replacement" for the Sony PSPwhich unleashes the full potential of your handheld, allowing you toboth use homebrew softwareand run UMD ISO games from your Memory Stick on the latest firmwarereleases while also enjoying the impressive features built into the operating system such as RSS feeds, WMA support etc. Currently the 2.71 firmware release is supported.
It is important to note that Epsilon BIOS is not standalonefirmware replacement but more like a bootloader. It works using thedual-firmware system provided by the Undiluted Platinum hardwaremodification by loading when the PSP is initially powered on, then oncerunning executes and "piggybacks" the real firmware stored in your PSP flash memory. Due to the way this works it is NOT possible to use Epsilon BIOS unless your PSP has an U.P. hardware modification installed.
- Runs alongside 2.71 firmware, so you get all the features of 2.71such as RSS feeds, web browser etc combined with the advantages ofhomebrew software and ISO loading.
- Allows execution of homebrew software in kernel mode, removingall limits previously in place while running homebrew on firmwareversions above 1.50.
- Ultra reliable, near transparent UMD emulation allowing users torun their games from a Memory Stick with ease, including games whichrequire 2.0+ firmware without rebuilding the ISO or relying on nastyhacks.
- Support for compressed ISO files for UMD emulation, allowing you to fit more games onto your Memory stick at one time.
- Built-in recovery menu which can be used to to update yourEpsilon BIOS installation or restore your PSP flash contents if itbecomes "bricked".
As described above, Epsilon BIOS can be compared to a "bootloader".It is stored on the U.P. flash memory and executed when your PSP ispowered on. Once Epsilon BIOS is running it loads and "piggybacks" thereal firmware from the PSP flash. Currently only 2.71 firmware issupported, you must
upgrade your PSP onboard firmware to 2.71 in order to use EpsilonBIOS. If you attempt to boot Epsilon BIOS with an unsupported firmwareversion you will be taken to the recovery menu where you can upgradethe PSP firmware. The great thing about Epsilon BIOS is that since the"bootloader" always runs before the real firmware we can apply whateverpatches are necessary to disable -
whatever protection Sony tries to add in the future, making a U.P. modified PSP using Epsilon BIOS very future proof.
With Epsilon BIOS you can run homebrew software (EBOOT files)directly from the OS main screen. Kernel mode applications are alsosupported meaning there are no limits when it comes to homebrewsoftware. Both 1.00 and 1.50 style EBOOT's are supported.
UMD emulation is handled almost transparently. You do not need tolaunch a separate application in order to load your UMD games from thememory stick, all the ISO's you have stored on your Memory stick arelisted alongside your homebrew applications in the "Game->MemoryStick" screen and executed from there. Copying new games to your Memorystick is easy, simply enable the USB connection and copy ISO's to the"ISOS" directory in the root of your memory stick. Please note thateach time you change the contents of the ISOS directory a cache filecontaining the icons etc for each game must be updated, and this willcause a slight delay while viewing the "Game->Memory Stick"
Compressed ISO's are supported for UMD emulation using our owncustom format, "Epsilon ZIP". Using the "Epsilon ZIP Tool" included inthe archive you can convert UMD ISO files into EZIP files and viceversa. Simply copy the EZIP files into the same location as normal ISOfiles in order to play them.
Epsilon BIOS includes a recovery mode which can be used to updatethe PSP onboard firmware, restore a bricked PSP or upgrade your EpsilonBIOS installation. If there are any problems while booting then youwill be presented with the recovery menu. To forcefully enter therecovery menu, hold SELECT+START when you power on the PSP.
Epsilon BIOS is broken into two distinct parts: the bootloader andthe core. The bootloader is programmed to U.P. flash from the PC and iswhat actually takes control of the system when you first power on yourPSP. The bootloader attempts to load the core installed in U.P. flash;if the core has not yet been installed or there is another problem youwill be taken to the recovery menu. When you first program the Epsilonbootloader onto your U.P. you will need to install the core separately
since it is not bundled inside the bootloader flash image.However, whenever an Epsilon BIOS core update is released you simplycopy the update file onto your Memory Stick then use the recovery menuto update the core. This system is much safer and more user friendlythan having to reprogram the U.P. flash from the PC each time youupdate which would be required if the bootloader and core wereintegrated.
Installing the Bootloader
1. Turn on the PSP while holding LEFT to enable U.P. programming mode
2. AFTER the PSP has turned on, connect the USB cable to the U.P.
3. Program the bootloader flash image (epsilonBootloader*.flash) to U.P using the flashing tool
4. Cold restart the PSP by cycling power
Installing/Updating the Epsilon BIOS Core
Updates and the initial installation of the Epsilon BIOS core arehandled through the Epsilon recovery menu. To enter the recovery menuhold SELECT+START while you power on the PSP. The procedure toinstall/upgrade the BIOS is as follows:
1. Copy EBUPDATE.BIN to the root directory of your memory stick. This can be done via the
recovery menu by selecting "Memory Stick USB" or with a card reader, PSP XMB etc
2. Select "Update Epsilon BIOS", then hit X to confirm
3. Once the installation/update is complete the PSP will power off.
Notes Regarding Homebrew
As the majority of homebrew software currently available isdesigned to run on the 1.50 kernel we decided that for compatibilityreasons it would be best to have Epsilon BIOS load the 1.50 kernelinstead of 2.x when running homebrew software. This is possible sincethe Epsilon BIOS bootloader is actually based on the 1.50 firmware sowhen running homebrew software the kernel is loaded from U.P. flashrather than PSP onboard flash. The only known issue with this methodrelates to wireless network configuration - since the 1.50 kernel doesnot support WPA encryption you will need to configure your PSP to useWEP if you wish to use WIFI enabled homebrew software.
To forcefully enter the recovery menu hold SELECT+START while youpower on the PSP. The Epsilon BIOS recovery menu from the 1.0bootloader has the following menu selections:
1. Memory Stick USB – Enables the USB connection between the PSPand PC for transferring files. This is the same as the USB connectionin the PSP XMB.
2. Update Epsilon BIOS – Installs an Epsilon BIOS core update fromthe memory stick. The update file must be named EBUPDATE.BIN and placedin the root directory of the memory stick.
3. Launch Firmware Updater – Launches an official Sony firmwareupdater EBOOT stored on the memory stick at /PSP/GAME/UPDATE/EBOOT.BIN.You may use this feature to both upgrade and downgrade your PSP onboardfirmware version. Please take note first of the following importantfacts:
a. Epsilon BIOS releases are only compatible with certain firmwareversions. If you flash your PSP to an unsupported version you will betaken to the recovery menu by the bootloader until such time as asupported firmware version is installed.
b. In order to downgrade your firmware certain files must bemodified in your PSP onboard firmware so the official Sony updater*thinks* you have a very early firmware version installed. There arealways risks involved with modifying your onboard firmware and such anaction can be potentially hazardous to your data. Please note that whenupgrading the firmware version no files need to be edited so thiswarning does not apply.
4. Restore onboard NAND – Used to “un-brick” a PSP by programming aknown good flash dump (such as a dump of 1.0 or 1.50 firmware) to yourPSP onboard NAND flash. The flash image must be a file called“nandImage.flash” in the root of the memory stick, in the same formatused by the UP flasher tool (512bytes user + 16bytes extra for eachpage, interleaved).
5. Shutdown PSP – self-explanatory :)
Q: Why do I get a 0x86660000 error when I try to launch a Sony firmware upgrade?
A: Epsilon BIOS blocks you from trying to install firmware versionsthat are not supported by the installed core. If you wish to upgrade toa new firmware, you might first need to upgrade Epsilon BIOS to aversion which supports said firmware.
Q: From firmware 2.6 and up, PRX files are protected with a newencryption method. How did you figure out how to decrypt these files?
A: As most people will now be aware, the discovery of the 2.6 kmodeexploit lead to decryption of modules using the new encryption method.However when we started working on this the kernel mode exploit wasunknown so we took a different approach to reach our goal, one thatdoesn’t rely on exploits so should allow us to easily hack new firmwarereleases in the future once Sony changes the encryption method again.Here’s how we did it - warning: this is a bit technical, whichunfortunately is required to give a proper answer. Since we couldn'tget a dump of kernel memory from a PSP running the 2.6 firmware, theonly way to figure out how to decrypt the 2.6 PRX files was todisassemble the IPL and see how this decrypted the files while the PSPis booting.
Unfortunately, Sony used a clever trick in the 2.6 IPL to preventhackers disassembling it. They read out some data from the reset vectorand use it to decrypt the main portion of the IPL code. The problemhere is that by the time we can run code on the PSP, any attempt toread out this data will be in vain as it gets scrambled inside the IPL.However, through some hardcore trickery we found a way to dump the dataat the reset vector which enabled us to decrypt the main portion of theIPL code and then use this to figure out how the 2.6 PRX files wereencrypted. The same encryption method and keys are used in 2.7 and2.71, so when 2.7 came out we had this dumped and decrypted veryquickly. There is nothing left now they can use to hide the IPL so whenthe 3.0 firmware eventually comes out its highly likely the encryptionwill have changed again but it
shouldn’t take too long to figure it out. Sorry to give you thebad news Sony.. the hackers win another round, you cannot hide yourfirmware from our eyes anymore