Chronoswitch

Chronoswitch is the evolution of a 6.31/6.35 downgrader created by Davee. It's original goal was to downgrade a PSP to 6.20 by using a kernel exploit to run a special PRX that spoofs index.dat and decrypts the official 6.20 update before launching it.

Compatibility

The current version of Chronoswitch (v7.2 as of this writing) does more than downgrade 6.35 to 6.20, it can be launched from and downgrade to many versions. Below is a list of compatible firmwares it can be run on and a list of firmware versions it can downgrade to.

Chronoswitch Can Be Started On:

6.61, 6.60, 6.39¹, 6.38, 6.35¹, and 6.31¹

¹: Support for these firmwares is broken in newest versions. If you need to downgrade from one of these, either upgrade to 6.61 first or use an older version of Chronoswitch

Chronoswitch Can Downgrade To:

Any 5.xx or 6.xx firmware that comes in EBOOT.PBP format