fixed_to_float.v

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module fixed_to_float (
	fixed_sign,
	fixed_mag,
	float_out
);

parameter FIXED_WIDTH = 8; // must not be > 32
parameter FIXED_FRACTIONAL = 4;

input fixed_sign;
input [FIXED_WIDTH-1:0] fixed_mag;
output [31:0] float_out;

	wire [7:0] exponent;
	wire [31:0] unscaled_mantissa = fixed_mag << (32-FIXED_WIDTH);
	wire [31:0] scaled_mantissa;
	wire [4:0] scale_distance;

	scale_up sc (.in(unscaled_mantissa),
				.out(scaled_mantissa),
				.distance(scale_distance));
		defparam sc .WIDTH = 32;
		defparam sc .WIDTH_DIST = 5;

	assign exponent = 8'd127 + (FIXED_WIDTH-FIXED_FRACTIONAL) - 1
						- scale_distance;

	// Zero is special and gets an exponent of 0, not "something very small"
	assign float_out = &scale_distance ? {fixed_sign,31'h0} :
					{fixed_sign, exponent, scaled_mantissa[30:8]};
	
endmodule