ring oscillator (ring.des) example

unit ring (in wire INP := '0; out wire ROUT;)

wire (2,2) I1 ; /* wire (rise_delay,fall_delay) name */
wire (1,1) I2 ;
wire (2,2) I3 ;
wire I4 ;

body

inv : A5 (I4;INP); /* gate_type:gate_name(input_name;output_name) */
nor : A1 (I2;I1,I4);
inv : A2 (I3;I2), A3 (I1;I3);
inv : A4 (ROUT;I3);
endunit