Use the Keyboard preference tool to configure the keyboard to simulate a mouse. To open the Keyboard preference tool, choose System ▸ Preferences ▸ Keyboard. The Mouse Keys options can be enabled by selecting the Mouse Keys tab.
"Allow to control the pointer using the keyboard" (Alt-A) - this determines if the keyboard can be used to control the mouse pointer.
Acceleration (Alt-C) - determines how quickly mouse motion will accelerate when keyboard directional keys are pressed.
Speed (Alt-S) - determines how quickly the mouse pointer will move when keyboard directional keys are pressed.
Delay (Alt-D) - determines how much (or if) keypresses may be dampened or ignored when keyboard directional keys are pressed.