// Decimal to Thermometer decoder
// Implements two options: 
// Start_Bit = 0: Decimal 0 equals thermometer 0
// Start_Bit = 1: Decimal 0 equals thermometer 1
// Change therm_bits variable for your needs!
// Author: A. Sidun
// Source: AnalogHub.ie

`include "constants.vams"
`include "disciplines.vams"
`define therm_bits 10						// define number of output bits here

module dec2therm(out);

output [`therm_bits-1:0] out;
voltage [`therm_bits-1:0] out;

parameter real vdd = 5;					// voltage level of logic 1 (V)
parameter real vss = 0;					// voltage level of logic 0 (V)
parameter integer Decimal_Code = 5; 	// input decimal code
parameter integer Start_Bit = 0;    	// defines if thermometer starts from 0 or 1

real dout[`therm_bits-1:0];					// internal result variable
genvar i;

analog begin

case (Start_Bit)
    0: begin	// Decimal 0 equals thermometer 0
		for(i=1;i<`therm_bits+1;i=i+1) begin
          		if(Decimal_Code!=i) begin
              		dout[i-1]=vss;
          		end
      		else begin
          		dout[i-1]=vdd;
      		end
		end
	end 

    1: begin	// Decimal 0 equals thermometer 1
		for(i=0;i<`therm_bits;i=i+1) begin
          		if(Decimal_Code!=i) begin
              		dout[i]=vss;
          		end
      		else begin
          		dout[i]=vdd;
      		end
		end
	end
endcase

// Plotting outputs
for (i=0; i<`therm_bits; i=i+1)
	    V(out[i]) <+ transition(dout[i],0,0);
end

endmodule