[PD] beginners Fiddle~ questions

[Conor]

Hi folks,

very new to this PD malarky... so please be a little patient.
I have ruditmentary question on the output of the fiddle~ object. I 
simply do not know on what type the pitch (left most output) is ? Is it 
in terms of MIDI(0-127), some arbitrary scale?
Seems to be mapping 1 per semitone. The fiddle~ in my patch has npoints 
arguments =  2048 ( i noticed that any size smaller produces a very 
erratic response), 1  for the number of pitches to output and the last 
two arguments empty. I was using a guitar(semi-acoustic) as input.
totally rookie question but has me stumped.

Conor