By Popular Demand!
module sqrt (clk,data,start,answer,done);
assign done = ~busy;
endmodule
module sqrt (clk,data,start,answer,done);
input clk,start;
input [7:0] data;
output [3:0] answer;
output done;
input [7:0] data;
output [3:0] answer;
output done;
reg [3:0] answer;
reg busy;
reg [1:0] bit;
wire [3:0] trial;
reg busy;
reg [1:0] bit;
wire [3:0] trial;
assign trial = answer | (1 << bit);
always @ (posedge clk)
begin
if (busy)
begin
if (bit == 0) busy <= 0;
else
bit <= bit - 1;
bit <= bit - 1;
if (trial*trial <= data)
answer <= trial;
answer <= trial;
end
else if (start)
begin
busy <= 1;
answer <= 0;
bit <= 3;
answer <= 0;
bit <= 3;
end
end
assign done = ~busy;