This is confirmed working, I just downgraded my ta-082 2.71 to 1.50 !!
Here is my guide step by step how you safelly downgrade.
Get this 3 files :
*
http://www.psp-hacks.com/file/982 (ta-082 downgrader)
*http://www.psp-hacks.com/file/4 (1.50 EBOOT)
*http://www.psp-hacks.com/file/922 (HEN-D)
Instructions: step1:charge your psp battery ,to be sure to 100%
step2:formatt your memory card,(i recommend to backup the folder SAVEDATA in psp folder so that you can play your games were you stopped) after that do a hard reset if you don`t know how just remove the battery and put it back!
step3: Copy the UPDATE and idstoragechange folders into /PSP/GAME/
step4: rename the the official sony 1.50 eboot to UPDATE.PBP and put it in the /PSP/GAME/UPDATE
step5:HEN-D= Copy the
dh folder(it is inside devhook folder!) to the root of your memstick.
Copy
pspbtknf_game, pspbtknf_updater, pspbtknf, patch(bin), h(bin) and systemctrl.prx file(this files are inside ms_root folder!)to the root of your memstick.
Copy the
HEND folder(it is inside psp folder!) into PHOTO folder.
Run HEN-D if you are not already running it by going to the photo menu and then entering the HEN-D.
one of three colors should come out:
A Blue Screen then a Green Screen! If it comes up with Red Screen that means it was not sucessfull installed. shut your PSP off(reset) and try again. IF it turns Blue Then Green, it was sucessful! It should restart your PSP.
if it freezes. don't worry. just turn it off and try again.
To check if you are already running HEN-D, go to system information in the system settings menu. It should say 2.71 HEN-D.
Hard reset = hold the PSP power switch up for about 15 seconds.
step6:go to game/memory stick and Execute the TA-082 idstorage change. It will change some keys of your idstorage needed to downgrade the ta-082. and agree by pressing x
step7:The program will exit to the XMB. Now again go to game/memorystick and execute the generic downgrade, which will show in the xmb
as "psp Update version X.YZ"
step8: The generic downgrader will downgrade your psp to 1.50. you will see the progress don`t touch anything!! till it finished!!
- At the end, it will ask you to press X to restart the psp. you'll receive a blue screen telling you to press O. Do it, and change your settings.
ps: Don't forget to put the folder SAVEDATA back so that you can load your game data