X-Git-Url: http://git.joshuawise.com/mandelfpga.git/blobdiff_plain/e03ccef9a0b8b9f76b0211b5b5063f49ed9df23e..cf311cdb0b57f208823dc48a589a084a29f0f568:/Main.v

diff --git a/Main.v b/Main.v
index 6762c0f..3e1e333 100644
--- a/Main.v
+++ b/Main.v
@@ -5,6 +5,8 @@
  * An implementation of a pipelined algorithm to calculate the Mandelbrot set
  * in real time on an FPGA.
  */
+ 
+/* verilator lint_off WIDTH */
 
 `define XRES 640
 `define YRES 480
@@ -69,20 +71,19 @@ module NaiveMultiplier(
 	always @(posedge clk)
 	begin
 		{ovf,out} <=
-			(((y[12] ? (x     ) : 0)  +
-			  (y[11] ? (x >> 1) : 0)  +
-			  (y[10] ? (x >> 2) : 0)) +
-			(((y[9]  ? (x >> 3) : 0)  +
-			  (y[8]  ? (x >> 4) : 0))+
-		    ((y[7]  ? (x >> 5) : 0)  +
-			  (y[6]  ? (x >> 6) : 0))))+
-			  
-			(((y[5]  ? (x >> 7) : 0)  +
-			  (y[4]  ? (x >> 8) : 0)+
-			  (y[3]  ? (x >> 9) : 0)) +
-			 ((y[2]  ? (x >> 10): 0) +
-			  (y[1]  ? (x >> 11): 0)  +
-			  (y[0]  ? (x >> 12): 0)));
+			(((y[12] ? (x       ) : 0)   +
+			  (y[11] ? (x[12:1]) : 0)   +
+			  (y[10] ? (x[12:2]) : 0))  +
+			(((y[9]  ? (x[12:3]) : 0)   +
+			  (y[8]  ? (x[12:4]) : 0))  +
+			 ((y[7]  ? (x[12:5]) : 0)   +
+			  (y[6]  ? (x[12:6]) : 0))))+
+			(((y[5]  ? (x[12:7]) : 0)   +
+			  (y[4]  ? (x[12:8]) : 0)   +
+			  (y[3]  ? (x[12:9]) : 0))  +
+			 ((y[2]  ? (x[12:10]): 0)   +
+			  (y[1]  ? (x[12:11]): 0)   +
+			  (y[0]  ? (x[12]): 0)));
 		sign <= xsign ^ ysign;
 	end
 
@@ -118,7 +119,7 @@ module MandelUnit(
 	wire [14:0] ri, diff;
 	wire [15:0] twocdiff;
 	wire r2sign, i2sign, risign, dsign;
-	wire [13:0] bigsum;
+	wire [14:0] bigsum;
 	wire bigsum_ovf;
 
 	reg [12:0] xd, yd;
@@ -132,8 +133,8 @@ module MandelUnit(
 	Multiplier i2m(clk, i[12:0], i[12:0], isign, isign, i2[12:0], i2sign, i2[13]);
 	Multiplier rim(clk, r[12:0], i[12:0], rsign, isign, ri[13:1], risign, ri[14]);
 
-	assign bigsum = r2[12:0] + i2[12:0];
-	assign bigsum_ovf = bigsum[13] | r2[13] | i2[13];
+	assign bigsum = r2[13:0] + i2[13:0];
+	assign bigsum_ovf = bigsum[14];
 	
 	assign twocdiff = r2 - i2;
 	assign diff = twocdiff[15] ? -twocdiff : twocdiff;
@@ -210,8 +211,8 @@ module Mandelbrot(
 	wire [13:0] nx, ny;
 	wire rxsign, rysign;
 	
-	assign nx = x + xofs;
-	assign ny = y + yofs;
+	assign nx = {2'b0,x} + {2'b0,xofs};
+	assign ny = {2'b0,y} + {2'b0,yofs};
 	assign rx = (nx[13] ? -nx[12:0] : nx[12:0]) << scale;
 	assign rxsign = nx[13];
 	assign ry = (ny[13] ? -ny[12:0] : ny[12:0]) << scale;
@@ -224,12 +225,14 @@ module Mandelbrot(
 	wire xsprop[`MAXOUTN:0], ysprop[`MAXOUTN:0];
 	wire [7:0] curiter[`MAXOUTN:0];
 	
-	reg [14:0] initx, inity, initr, initi;
+	reg [12:0] initx, inity;
+	reg [14:0] initr, initi;
 	reg [7:0] initci, initb;
 	reg initxs, initys, initrs, initis;
 	
 	// Values after the number of iterations denoted by the subscript.
-	reg [14:0] stagex [2:1], stagey [2:1], stager [2:1], stagei [2:1];
+	reg [12:0] stagex [2:1], stagey [2:1];
+	reg [14:0] stager [2:1], stagei [2:1];
 	reg [7:0] stageci [2:1], stageb [2:1];
 	reg stagexs [2:1], stageys [2:1], stagers [2:1], stageis [2:1];
 	
@@ -245,10 +248,10 @@ module Mandelbrot(
 		inity <= (state[2]) ? ry :
 	               (state[0]) ? stagey[1] :
 	               (state[1]) ? stagey[2] : 0;
-		initr <= (state[2]) ? rx :
+		initr <= (state[2]) ? {2'b0,rx} :
 	               (state[0]) ? stager[1] :
 	               (state[1]) ? stager[2] : 0;
-		initi <= (state[2]) ? ry :
+		initi <= (state[2]) ? {2'b0,ry} :
 	               (state[0]) ? stagei[1] :
 	               (state[1]) ? stagei[2] : 0;
 		initxs <= (state[2]) ? rxsign :
@@ -289,6 +292,9 @@ module Mandelbrot(
 			3'b001: state <= 3'b010;
 			3'b010: state <= 3'b100;
 			3'b100: state <= 3'b001;
+		`ifdef isim
+			default: begin $display("invalid state"); $finish; end
+		`endif
 			endcase
 	
 		// Data output handling
@@ -373,13 +379,19 @@ module Logo(
 endmodule
 
 module MandelTop(
+`ifdef verilator
+	input pixclk, mclk,
+`else
 	input gclk, output wire dcmok,
+`endif
 	output wire vs, hs,
 	output wire [2:0] red, green, output [1:0] blue,
 	input left, right, up, down, rst, cycle, logooff,
 	input [2:0] scale);
-
-	wire pixclk, mclk, gclk2, clk;
+	
+`ifdef verilator
+`else
+	wire pixclk, mclk, clk;
 	wire dcm1ok, dcm2ok;
 	assign dcmok = dcm1ok && dcm2ok;
 	
@@ -396,7 +408,8 @@ module MandelTop(
 		.CLKFX_OUT(mclk),
 		.LOCKED_OUT(dcm2ok)
 		);
-	
+`endif
+
 	wire border;
 	wire [11:0] x, y;
 	reg [13:0] xofs = -`XRES/2, yofs = -`YRES/2;
@@ -409,7 +422,7 @@ module MandelTop(
 	wire [1:0] mandelb, logob;
 	
 	SyncGen sync(pixclk, vs, hs, x, y, realx, realy, border);
-	Mandelbrot mandel(mclk, pixclk, x, y, xofs, yofs, cycle ? colorcycle : 0, scale, mandelr, mandelg, mandelb);
+	Mandelbrot mandel(mclk, pixclk, x, y, xofs, yofs, cycle ? colorcycle : 8'b0, scale, mandelr, mandelg, mandelb);
 	Logo logo(pixclk, realx, realy, logoenb, logor, logog, logob);
 	
 	assign {red,green,blue} =