PSP 1.5
There are several examples in which people have downgraded from psp 2.0 to psp 1.5. The reason of this alteration is that it could become possible to play pirated psp games as well as install Sega Genesis and Super Nintendo emulators. Also, the downgrade to psp 1.5 is done as it is possible to upgrade the psp 1.5 to any version. If the upgrade is done to psp 3.51, it is possible to download games and run the applications.
It must be remembered that the Psp system can be downgraded to psp 1.5, by converting the Psp battery to a pandora’s battery. The items required are an original Psp battery that has more than 50 percent charge and a memory stick pro duo with minimum 1 GB memory.
Procedure for download
The procedure is as follows – the Home button on the left bottom of the Psp has to be pressed. The arrow keys have to be used to move to the Settings area. The up and down keys have to be used to go to System Settings. The X button must be pushed and the option ‘Format memory stick’ must be found out. For this option, the X button must be again pushed. The Psp will ensure that the memory stick is to be reformatted. If Yes is selected, the Psp will be physically formatted in some seconds.
Hacking
In the year 2005, the psp 1.5 was hacked. From that time, it became possible for the psp 1.5 users to run homebrew psp software. This was discovered by the guys at psp-dev. This is a very simple concept. It is very surprising that this concept is actually workable and nobody found it earlier. This requires two memory sticks. The hacked eboot is put on one memory stick. The actual ELF executable is put on the second memory stick with the same name. When the hacked eboot is launched, it is required to swap the memory stick for another one and run the eunencrypted file. Due to some reason, the header is not rechecked and the executable is run from address 0.