Vita Half-Byte Loader is a project to port the PSP homebrew loader HBL to the Playstation Vita,
through the PSP emulator on the Playstation Vita.

Half-Byte Loader (HBL) is an open source Homebrew Loader for the Sony PSP and the PS Vita. It allows to play fan-made
games on any PSP up to firmware 6.60, and on the Vita up to firmware 1.61. HBL allows to run emulators for the
Game Boy, Nintendo 64, Sega Megadrive, NES, Super NES… and many other applications.


How to Install and Run VHBL

•     It is *strongly* recommended that you turn of all wireless connections on your PS Vita, and that you use OpenCMA
  on your PC instead of the regular CMA. This is recommended because otherwise your console has a way to force
  you to upgrade the firmware even before you get a chance to use the exploit.

  

• Extract this HBL archive in your CMA PSP Savedata folder. It is a folder on your PC named
  PSSAVEDATA/[lots of random characters here]. If you don’t know where it is, check your settings in CMA

  

• Connect your PS Vita to the PC through the CMA, it should give you the possibility to copy the
  savedata from your PC to the Vita. If not, you probably extracted it in the wrong folder.

  

• To run HBL, start the Motorstorm game, select “Load” in the savegame menu, open the HBL
  savegame, then go to “Wreckreation > Time Attack” and select “No”. At this point, HBL should start.

VHBL is now available for download, for the people who are lucky to own an unpatched version of Motorstorm
Arctic Edge on their vita. Download the version that matches your version of the game:

Downloads:
EU Version
JP Version
KR Version (Seen at least on the HK store)
US Version (not very useful since wee're not able to dl the game on to our Vitas)

Source