For homebrew enthusiasts with TA-082 or newer motherboards, who have a patched idstorage key and cannot upgrade their 3.11 firmware to 3.50 to use the 3.50 downgrader, and don't have access to Pandora's Battery, team N00bz has a solution for your extremely specific problem.
Their new 3.11 downgrader will let you go down to firmware 1.50, at which point you could then do lots of homebrew goodness. You will need a copy of Lumines to pull off the downgrade. Detailed instructions can be found here. As usual, we must warn you that there is a risk of bricking your PSP, so use at your own risk.
Much to the dismay of Sony, it appears that the homebrew community has finally created a downgrader for firmware 3.50. With almost any copy of Lumines, PSP owners will be able to have their systems revert back to an older firmware. Visit N00bz for the complete directions, but make note of one of the requirements: "Sufficient intelligence and English language skills to be able to carefully and throroughly read the instructions."
Downgrading a system CAN BE RISKY, and MAY CAUSE YOUR SYSTEM TO BE INOPERABLE (or "bricked"). Also, you will be voiding your system's warranty by using this hack. If you're willing to take the plunge, feel free. Once you get to 1.50, we highly recommend that you install one of Dark_Alex's custom firmware packages, to ensure compatibility with current game titles.
You can find more info at Noobz. Remember: you are downgrading at your own risk, and no one can be held responsible if you brick your system. Take precaution. Once you downgrade, you can always upgrade to one of Dark_Alex's custom firmware options.
A public message announcement from the PSP Fanboy team: Stop asking if you can downgrade your system. Currently, downgraders only work for PSPs with firmware 2.80 or below. Constantly leaving comments about downgrading from 3.03 will not get responses.
So, what are you supposed to do then? N00bz, "homebrew without a clue," answers some of your burning questions. They note a few key points: there is a "kernel mode exploit" in all PSPs, up to version 3.03, that seems to be unchanged. Once a "user-mode exploit" can be found, it will be theoretically possible to run homebrew on all PSPs--even downgraders should work.
But when will this happen? Who knows. Certainly, there are hard-working homebrew coders trying to find exploits in all of Sony's latest. However, N00bz recommends that if you're ever serious about switching over to homebrew, you should stop upgrading your PSP altogether. 3.04 or whatever future firmware upgrade Sony releases will most likely address these exploits; and it should be much easier to run exploits on 2.81 versus 3.03. There's no guide as to when the homebrew community will release something, but we advise you: please be patient. Personally, I'll keep upgrading to Sony's official firmware because I actually like playing legal games.
[Update 1: Looks like I offended a few of you with my overly bitter comment. I'd like to apologize to those of you that do actually use your homebrew PSPs in a legit manner. As an acknowledgement of the harsh tone I took, I will not delete the comment. Sorry to those that were offended: you are clearly upstanding in an industry where many people take game developers for granted.]
Some people are wary that the use of downgraders will leave their systems essentially useless, or "bricked" as they say. The process isn't the simplest to follow, and copying over system files is always a dangerous thing. However, the homebrew team at N00bz have created the "safest" downgrader yet. It has built-in security checks, support for TA-082 and TA-086 motherboards, and includes most every file you'll need to revert your 2.80 PSP down to PSP 1.50.
This doesn't mean that it's 100% fool-proof, as the warning attached to the downgrader states. However, there's also a new alternative: by downloading and installing HEN-D to a PSP version 2.80, you'll be able to launch a good deal of homebrew without having to downgrade at all.
Homebrew enthusiasts know that there's a special kind of PSP that can't downgrade... until now. Some PSPs have a TA-082 motherboard which prevents downgrading to a homebrew-capable firmware, but whiz-kid Dark_Alex seems to have worked his programming magic yet again and has created a downgrader for y'all running firmware 2.71. Considering the technical proficiency this guy is capable of, shouldn't he be hired by Sony by now?
There's always someone out there that updated their PSP, only to regret it moments later. Well, for those of you that have been patient enough not to upgrade past 2.80, an "easy" way of downgrading to homebrew-compatible 1.50 has been released. This guide from PSP Vault will help you every step of the way, but they warn:
-If you have a TA-082 motherboard in your PSP, no [sic] not even attempt to downgrade. -If you are clueless and don't feel that you can follow this guide step-by-step, do not attempt to downgrade. -If you have a fear of bricking your PSP and are nervous, I will say this guide has been used several times over, but perhaps you should wait for some sort of "safe downgrader".
If the scary red text doesn't change your mind about downgrading, then you're ready to go! First, you'll have to download eLoader and xLoader, PatchSFO and finally the downgrader program. Make sure you have a USB cable ready to connect your PSP to your PC. You'll run the downgrader, but watch out for the next few steps, indicated in the guide. You don't want to brick your system, do you? With 3.02 firmware emulation entirely possible, it appears that a whole new slew of people can now be introduced to homebrew.
Downgraders are popular in the PSP homebrew scene, as they can revert a PSP to an earlier firmware which can more readily play homebrew applications. However, one type of motherboard prevents such modifications: the TA-082. When someone called dark_thug released a downgrader for TA-082 PSPs, people were skeptical. The community, however, embraced it with open arms.
Until they realized it was a fake. Chaos Zero, who originally released the malfunctioning program to the masses, went on record, publically apologizing for the whole incident. As stated on PSP-HaXors, "It was fake, and we've all seen fakes in the past. And will probably continue to see them. Instead of pointing fingers at the testers, it's better to just move on."
While it doesn't appear any PSP systems were bricked during this incident, it is scary to know that there are malicious people out there trying to create hoax programs that could potentially harm your PSP. While some of the benefits of homebrew may seem appealing, there are certainly a few dangers that come with the territory.
Some modern PSPs are manufactured with hardware that prevented downgrading to older firmware. They can be identified by opening the UMD drive and looking inside: if numbers appear inside (pictured right), then the system was unable to downgrade... that is, until now. Programmer 0okm has developed SoftDown" for TA-082 users, and is willing to work with you one-on-one via e-mail to get your system downgraded. Of course, like he says, you'll have to trust him with your e-mail address, PSP serial number and your firmware data. If you're ready to start taking the first steps towards a very homebrew-friendly system, check out 0okm's website for more info.
A lot of you seem confused about the whole 2.71 downgrading process. Thankfully, Xtrusion has made a super-simple way for the less technically inclined to downgrade their PSPs. Simply visit his website, and get the "Full" installer for 2.71 PSPs. Once again, make sure you don't have a TA-82 PSP or this will not work. Also, remember that there is always the chance of bricking your system, so please USE AT YOUR OWN RISK. REMINDER: If you successfully downgrade your system, you'll have to follow some steps to get homebrew running on your handheld. Truth be told, if this is still too difficult for you to understand, I highly recommend not jumping into homebrew. You can seriously mess up your system if you don't know what you're doing, so please: make sure you're mindful of what you're doing. Bricking a PSP won't be too much fun. If you can stomach these fairly simple instructions, then kudos to you: have fun!
(P.S. Thanks to all the people that have left helpful comments over the past few days! Your help is much appreciated!)
Downgraders allow people who regret having upgraded their PSP firmware to take a step back in time. Previous downgraders only worked up to 2.5 firmware, but today's downgrader will work with PSPs, firmware 2.71. This program takes advantage of the libtiff exploit uncovered a few days ago and is provided by Dark_Alex, with the help of Mathieulh. As long as you follow the directions, your system shouldn't be bricked, but as is the case with any program that alters crucial system software, you should run the program AT YOUR OWN RISK. It's not going to be easy, but if you're determined, this is the key.
See the development website to get the file. Before you begin, make sure you do not have a TA-082 PSP. Check the picture to the right to see how to identify your system. If you see that text in your UMD reader, you're out of luck... for now (the homebrew community is hard at work for you too!).
[Update 1: Links to the original source of the downgrader. You gotta give credit where it's due! Thanks, DCEmu!] [Update 2:QJ reader Mr. Dank has provided a video of the process. Watch after the cut.] [Update 3: Just visit this page to see a really easy way of using this software.]
Homebrew can be a little confusing and intimidating. So, I guess it's a little understandable when tonsofconfusedpeople write comments in the blog, having absolutely no idea what the latest libtiff exploit does. Sure, they could've read the article, or even the helpful comments, but remember: I'm at your service. While I could explain again that the Hello World demo is just a demonstration of the potential of homebrew running on 2.0+ PSPs, I'll let this cosplaying pirate from PSP Hacking 101 explain it all. Arg, everybody likes pirates, matey!
In other news, according to PSP Fanboy reader craig, a downgrader for 2.71 should be coming some time soon today or tomorrow. Check PSP Fanboy regularly to see the latest news!
Chalk the tardiness of reporting this up to the holiday, but the final version of the 2.50/2.60 downgrader has been released to the eager PSP homebrew community, one who's strength already rivals that of your favorite super hero. Of course, it goes without saying that attempting to utilize this program is purely an "attempt at your own risk" endeavor. Also, it should be noted that certain PSPs will not be capable of utilizing this program, so make sure you read the instructions carefully before giving it a go.
For homebrew enthusiasts with TA-082 or newer motherboards, who have a patched idstorage key and cannot upgrade their 3.11 firmware to 3.50 to use the 3.50 downgrader, and don't have access to Pandora's Battery, team N00bz has a solution for your extremely specific problem.
There's always 
