PlayStation Portable system software
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The PlayStation Portable system software is the official firmware for the PlayStation Portable. It uses the XrossMediaBar as its user interface, similar to the PlayStation 3 console. Wikipedia
Default user interface: XrossMediaBar
Initial release: December 12, 2004; 19 years ago (as 1.00)
OS family: Proprietary
Source model: Closed source
Update method: Direct Download; Download via PS3; Download via PC; Universal Media Disc
Working state: Discontinued