Updating psp via usb
Having the power supply cut in the middle of a regular Sony authorized firmware upgrade could very quickly turn your 0 PSP into a 0 doorstop.Such an error in a normal firmware upgrade, though, would be covered under Sony’s warranty.It notes that your preferences are fragged and that you need only hit the O button to restore some default-ish settings. Some hackers have claimed that unplugging the AC adapter and pulling the battery when this warning appeared resulted in them having a PSP running 1.5 firmware capable of running homebrew, but retaining the 2.0 browser.However, you should never leave the PSP plugged in when you remove the battery (I fried one PSP this way), and a few people have reported that following those directions turned their PSPs swiftly into nonfunctional bricks.
Finally, the pieces fell in place when someone thought to overwrite the PSP’s System Information during this error, so that a PSP running Version 2.0 of the firmware would be fooled into thinking that it was running Version 1.0.
A simple substitution of a 1 for a 2, and suddenly you are able to run the 1.5 Software Update to replace the Version 2.0 firmware, effectively downgrading your system to a more hacker- and homebrew-friendly version of the firmware.
Keep in mind that working with firmware is always risky.
Run homebrew at will If you really love your PSP’s browser and don’t really want to give it up, don’t worry.
Simply back up all the browser-related files from your Memory Stick before downgrading.