A firmware file that is used by many MP3 and MP4 players that run the PortalPlayer chipset. These firmware files update or change the low-lying software of the player and changes the way that the OS handles the calls to the chip. Because of that, it is important to use the correct firmware for your player and to use an official firmware rather than a third-party one which could damage your player irreparably.

These firmware files may further contain the themes, images, and styles that the players it updates use.