(*) mindev  : take closest input value .
if | out_im - in1_im | < |out_im - in2_im|
out_im = in1_im;  else   out_im = in2_im;
command : mindev in1_im , in2_im , out_im 
default : mindev    A   ,    B   ,    C
range   :         <A-D> ,  <A-D> ,  <A-D>  
