sir, what do you mean by parameter automation? how will the yamaha P-80 help me in recording besides having to use it to record MIDI tracks?
Let's look at what your P80 can do in terms of midi.
First of all, it's an 88-key note-entry device. You can have up to 2 tracks with it's built-in sequencer, each track can have it's own midi channel and patch (voice) assignment. Unfortunately, it lacks some essentials to make it a good controller like pitch and modulation wheels, aftertouch, and a data slider - it's these additional controls that open up midi to additional control. That's why synthesizers often have these controls; a few even have knobs and sliders to control additional parameters.
Midi isn't just notes. It's also bending notes with the pitch wheel, adding some vibrato with the mod wheel - use can even use the mod wheel to control other parameters besides vibrato. Dig in with enough pressure on the key bed to activate aftertouch (if your keyboard supports it) for opening up a filter, or whatever aftertouch is assigned to. If you have a controller keyboard with knobs, you can sweep a filter with resonance for those trance sweeps, or you can use those same knobs to control reverb amount and reverb time, how much chorus is added during a solo... whatever parameter is open to you.
If you have Sonar (or Cubase; Logic Pro Audio/Digital Performer if you're on a Mac), load a softsynth like TTS-1. Use the P80 for note entry, or draw in notes with a mouse. Next, try to draw in automation; in Sonar, open up the piano roll view (PRV) for the midi tracks you recorded and in the velocity window below, draw a line thru the velocities shown. You can now alter velocities of each individual note, aside from that, you can alter the length of the note. Now, change the velocity view into something like reverb (CC#91), and draw a line in the velocity/controller window. Now playback the track. You should hear velocities and reverb changing as the track is played. Intriguing, isn't it? Now imagine tweaking every single parameter open to you; the possibilities then become endless.
Let's face it, though. Without additional controls at your disposal, the P80 only becomes a note entry device. You will need a different controller or keyboard that allows you to control these parameters in realtime. Most keyboard midi controllers now come with these additional knobs. sliders and wheels. If you don't need a keyboard, you can always get an alternative controller such as the Behringer BCR-2000 which contains 32 rotary encoders! Pair this wih a DAW like Sonar, Cubase or Nuendo, and open up a whole new world of midi.