Add button dejitter

Jamesits · Jamesits · commit e04518b83298 · 2017-12-30T15:32:34.000+08:00
diff --git a/Dejitter/ButtonDejitter.v b/Dejitter/ButtonDejitter.v
@@ -0,0 +1,86 @@
+`timescale 1ns / 1ps
+//////////////////////////////////////////////////////////////////////////////////
+// Company: 
+// Engineer:       James Swineson
+// 
+// Create Date:    14:47:27 12/30/2017 
+// Design Name:    ButtonDejitter
+// Module Name:    ButtonDejitter.v
+// Project Name:   ButtonDejitter
+// Target Devices: XC6LX16
+// Tool versions: 
+// Description: 
+//
+// Dependencies: 
+//
+// Revision: 
+// Revision 0.01 - File Created
+// Additional Comments: 
+//
+//////////////////////////////////////////////////////////////////////////////////
+
+// Generated by the following python code:
+//   for i in range(1, 32): print("(x <= {})?{}:\\".format(2**i, i))
+// we end at 4294967295 since default int is 32 bit.
+// use WIDTH'dxxxx if larger int is needed.
+// the last -1 is used to indicater no LUT value error.
+`define CLOG2(x) \
+(x <= 2)?1:\
+(x <= 4)?2:\
+(x <= 8)?3:\
+(x <= 16)?4:\
+(x <= 32)?5:\
+(x <= 64)?6:\
+(x <= 128)?7:\
+(x <= 256)?8:\
+(x <= 512)?9:\
+(x <= 1024)?10:\
+(x <= 2048)?11:\
+(x <= 4096)?12:\
+(x <= 8192)?13:\
+(x <= 16384)?14:\
+(x <= 32768)?15:\
+(x <= 65536)?16:\
+(x <= 131072)?17:\
+(x <= 262144)?18:\
+(x <= 524288)?19:\
+(x <= 1048576)?20:\
+(x <= 2097152)?21:\
+(x <= 4194304)?22:\
+(x <= 8388608)?23:\
+(x <= 16777216)?24:\
+(x <= 33554432)?25:\
+(x <= 67108864)?26:\
+(x <= 134217728)?27:\
+(x <= 268435456)?28:\
+(x <= 536870912)?29:\
+(x <= 1073741824)?30:\
+(x <= 2147483648)?31:\
+(x <= 4294967295)?32:\
+	-1
+
+module ButtonDejitter #(
+		parameter COUNT_TO = 5000000,
+		parameter DATA_WIDTH = `CLOG2(COUNT_TO) + 1
+	)(
+    input BTN_IN,
+    input CLK,
+    output BTN_OUT
+    );
+
+reg DEJITTERED = 0;
+reg [DATA_WIDTH:0] count = 0;
+
+assign BTN_OUT = DEJITTERED;
+
+always @(posedge CLK) begin
+	if (BTN_IN != DEJITTERED) count = count + 1;
+	else count = 0;
+	
+	if (count == COUNT_TO) begin
+		DEJITTERED = BTN_IN;
+		count = 0;
+	end
+end
+
+endmodule
diff --git a/Dejitter/ButtonDejitterTest.v b/Dejitter/ButtonDejitterTest.v
@@ -0,0 +1,90 @@
+`timescale 1ns / 1ns
+
+////////////////////////////////////////////////////////////////////////////////
+// Company: 
+// Engineer:      James Swineson
+//
+// Create Date:   14:57:18 12/30/2017
+// Design Name:   ButtonDejitter
+// Module Name:   ButtonDejitterTest.v
+// Project Name:  ButtonDejitter
+// Target Device: XC6LX16
+// Tool versions:  
+// Description: 
+//
+// Verilog Test Fixture created by ISE for module: ButtonDejitter
+//
+// Dependencies:  ButtonDejitter.v
+// 
+// Revision:
+// Revision 0.01 - File Created
+// Additional Comments:
+//
+// The following test runs for ~0.04s.
+// 
+////////////////////////////////////////////////////////////////////////////////
+
+module ButtonDejitterTest;
+
+	// Inputs
+	reg BTN_IN = 0;
+	reg CLK = 0;
+
+	// Outputs
+	wire BTN_OUT;
+
+	// Instantiate the Unit Under Test (UUT)
+	ButtonDejitter #(
+		.COUNT_TO(250000)
+	)uut (
+		.BTN_IN(BTN_IN), 
+		.CLK(CLK), 
+		.BTN_OUT(BTN_OUT)
+	);
+	
+	// 100 MHz Clock
+	always @* CLK <= #10 ~CLK;
+
+	initial begin
+		// Initialize Inputs
+		BTN_IN = 0;
+
+		// Wait 100 ns for global reset to finish
+		#100;
+        
+		// Add stimulus here
+		
+		// Note: delay = cycles * time per cycle (#10)
+		
+		// should trigger
+		BTN_IN = 1;
+		#6000000;
+		
+		BTN_IN = 0;
+		#6000000;
+		
+		// should not trigger
+		BTN_IN = 1;
+		#4000000;
+		BTN_IN = 0;
+		#1000000;
+		BTN_IN = 1;
+		#3000000;
+		BTN_IN = 0;
+		
+		// should trigger
+		BTN_IN = 1;
+		#6000000;
+		
+		// should not trigger
+		BTN_IN = 0;
+		#4000000;
+		BTN_IN = 1;
+		#1000000;
+		BTN_IN = 0;
+		#3000000;
+		BTN_IN = 1;
+	end
+      
+endmodule
+
diff --git a/Dejitter/RTL.png b/Dejitter/RTL.png
diff --git a/README.md b/README.md
@@ -28,6 +28,7 @@
 * 寄存器
 
   * 移位寄存器
+* 按键消抖
 
 ## 版权
 
