From StrategyWiki, the free strategy guide and walkthrough wiki

• / : Move/Turn the character; scroll through menu choices
• and : Rotate through weapons
• : Directional lock (character faces the same way when you move)
• : Movement lock (character stays in the same spot but can turn)
• : Dims/Undims HUD
• : Pauses/Unpauses; select options; skips cut-scenes
• : Activates lock-on weapon
• : Cancel
• : Fire active weapon (non-lock-on)
• : Spin-dodge; roll-dodge; confirm