Probably the differences between them will display the codes related to blocking memory stick tech.
6.20 OFW for PSP1000 PSP2000 PSP3000
http://g.ho.st/public/users/~B6862FD182E0C...tml?language=en
6.20 OFW for PSPgo
http://g.ho.st/public/users/~B6862FD182E0C...tml?language=en
6.20 OFW for PSP1000 PSP2000 PSP3000
http://g.ho.st/public/users/~B6862FD182E0C...tml?language=en
6.20 OFW for PSPgo
http://g.ho.st/public/users/~B6862FD182E0C...tml?language=en