I'm trying to hack my psp 1000 that has 6.37 firmware and I would like to know how would I use a half-byte loader and how to place in my psp.
This provides you with the download link. Click the link that says HBL rev 113 (recommended link), and start the download. Once it has finished, copy this folder to your PSP. No specific directories therein, just to the place where you would START putting things on.
