[GUIDE] 2.80 to 1.50 Downgrade - Tested Twice!!!!!
Okay, I just downgraded my 3.02 OE-A to 1.50, updated to 2.80, downgraded to 1.50, went back up to 2.80, and downgraded again!!! Here's the ultimate guide on how to NOT brick your PSP with 0okm's luverly downdater.
1. Verify that your PSP is NOT a TA-082. To check, eject the UMD tray, and pull out andy disc inside. Then turn your PSP upside down and peer inside. If you see the characters "IC1003" written on the green mobo, you have a TA-082, and should not attempt this, or you'll get a 100% bricked PSP. If you see ANYTHING else, especially what I have, "IC6001", then you're good to go.If you don't see anything, I think you're good, but check harder to make sure anyways. It's pretty far back there.
Several pics to help ID your PSP:
2. Obtain a friend with a 1.50, 2.71 SE, or 3.02 OE. If they have 1.50, have them update and then downgrade (go to 2.71 and use the generic downgrader) or just downgrade to 1.50. This is to ensure they have a CLEAN firmware, no Custom Firmware, gameboots, etc.
3. Have your new friend back up all his/her files on their memstick, then go to Settings > System Settings > Format Memory Stick. Also have them Go to Settings > System Settings > Restore Default Settings.
4. Have them extract these folders into ms0:\PSP\ (ms0 is your PSP's memstick drive letter).
4.5. Also extract the downhelper and downhelper% folders into ms0:\PSP\GAME. Get them here.
5. Have them REBOOT their PSP.
6. Have them run the DownHelper program.
7. Have them REBOOT their PSP.
8. Have them run the IPL Dumper program.
9. Go to USB and copy the DOWNDATER folder from their memstick to a PC.
10. Enter the folder, go to the PRX folder, and ensure that there is a FW150_ipl.bin file, around 220KB. If not, re-run the IPL Dumper.
11. Format YOUR memory stick.
12. Unpack these files into ms0:\PSP\ (ms0 is the drive letter of your PSP).
13. Copy the DOWNDATER folder into ms0:\ (The root of your memstick. NOT MS_ROOT, the MAIN "folder", so you're not in any fodler, if that makes sense.).
14. Restore YOUR default settings.
15. Reboot YOUR PSP.
16. Go to The Photo section, wait till you see the icons, and enter the xLoader folder. THIS IS VERY IMPORTANT. DO NOT USE THE ELOADER.
17. Once you see a corrupted data icon, it is safe to exit. If your PSP crashes, retry.
18. Go to the Game section, and Memory Stick. Choose the only icon that should be there.
19. Press O to flash the 1.50 dump. ONLY DO THIS WHEN YOU HAVE THE POWER CABLE PLUGGED IN AND YOUR BATTERY IS AT LEAST TWO BARS.
X. Enjoy your 1.50 firmware!!!!!
Note that this guide is somewhat paranoid. But, it is almost guaranteed to work.
I decided to use the manual downdater instead of the "easy" one because with the manual, you use a dump YOU KNOW is good. Maybe the one included in the "easy" downdater isn't clean!? Itprobably is, but this method I KNOW to work,so I reccommend it. Plus, it's k00ler ^_^.
Tell me what you think, please!
UPDATE: I obtained another friends 1.50 dump, and by looking at which files have the same md5 between us, I found that the IPL of the files in the PRX folder should always have the same checksum. Go to http://www.flashplayerpro.com/MD5Che...D5Checksum.htm to check your files and see if they should work. If you know that your dump was obtained using this proccess to the letter, though, and the md5s are still off, feel free to downdate anyways.
UPDATE: If you get a message saying "NOT TA-079~081", then you most likely have a TA-082. If you are POSITIVE you don't (Refer to step #1), then reformat the mestick and restore default settings, and try again. It should eventually go.