PSP v1.0 users can now back up their own firmware and then upgrade to v1.50 and then restore their v1.00 firmware with this new release from 0okm
Heres the info from the site
Restore Your FW1.00 to "Default Setting"
Use FW1.00B(FW1.00 Backup Tools) to Backup Your FW1.00
Update Your PSP to FW1.50
Use FW1.00R(FW1.00 Restore Tools) to Restore Your PSP to FW1.00
Q : Why the Tools say "Fatal error: Power NOT Online or Battery NOT Exist or BatteryLife < 50%" ?
A : When you Restore Your PSP FW, you need to Connect the AC adaptor & with BatteryLife > 50%,
Otherwise the Tools will Terminate.
Q : Why the Tools say "Fatal error: BadBlock find, Terminate" ?
A : Because this Tools NOW not support NAND Flash had BadBlock, so the Tools will Terminate.
Q : Why the Tools say "Fatal error: FW Data NOT Matched" ?
A : Because this Tools just for Backup & Restore your own PSP with FW1.00,
so you can't use other PSP's DATA.
Q : why won't it allow _anyone_ with a 1.50 to downgrade ?
A : Because Make a Downgrader with Unofficial NAND Flash Write is Very Very Dangerous !!
Q : why in Backup file have most "can't read Page from sceNand" ?
A : Because if the Nand Page has not used, it will "can't read Page from sceNand"
Extract Password is : I agree use this program at My own RISK!
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