1 files changed, 151 insertions, 0 deletions
diff --git a/fpga/usrp2/control_lib/fifo_tb.v b/fpga/usrp2/control_lib/fifo_tb.v
new file mode 100644
index 000000000..616fe4ee7
--- /dev/null
+++ b/fpga/usrp2/control_lib/fifo_tb.v
@@ -0,0 +1,151 @@
+module fifo_tb();
+   
+   reg clk, rst;
+   wire short_full, short_empty, long_full, long_empty;
+   wire casc2_full, casc2_empty;
+   reg 	read, write;
+   
+   wire [7:0] short_do, long_do;
+   wire [7:0] casc2_do;
+   reg [7:0]  di;
+
+   reg 	      clear = 0;
+   
+   shortfifo #(.WIDTH(8)) shortfifo
+     (.clk(clk),.rst(rst),.datain(di),.dataout(short_do),.clear(clear),
+      .read(read),.write(write),.full(short_full),.empty(short_empty));
+   
+   longfifo #(.WIDTH(8), .SIZE(4)) longfifo
+     (.clk(clk),.rst(rst),.datain(di),.dataout(long_do),.clear(clear),
+      .read(read),.write(write),.full(long_full),.empty(long_empty));
+   
+   cascadefifo2 #(.WIDTH(8), .SIZE(4)) cascadefifo2
+     (.clk(clk),.rst(rst),.datain(di),.dataout(casc2_do),.clear(clear),
+      .read(read),.write(write),.full(casc2_full),.empty(casc2_empty));
+   
+   initial rst = 1;
+   initial #1000 rst = 0;
+   initial clk = 0;
+   always #50 clk = ~clk;
+   
+   initial di = 8'hAE;
+   initial read = 0;
+   initial write = 0;
+
+   always @(posedge clk)
+     if(write)
+       di <= di + 1;
+   
+   always @(posedge clk)
+     begin
+	if(short_full != long_full)
+	  $display("Error: FULL mismatch");
+	if(short_empty != long_empty)
+	  $display("Note: EMPTY mismatch, usually not a problem (longfifo has 2 cycle latency)");
+	if(read & (short_do != long_do))
+	  $display("Error: DATA mismatch");
+     end
+   
+   initial $dumpfile("fifo_tb.vcd");
+   initial $dumpvars(0,fifo_tb);
+
+   initial
+     begin
+	@(negedge rst);
+	@(posedge clk);
+	repeat (10)
+	  @(posedge clk);
+	write <= 1;
+	@(posedge clk);
+	write <= 0;
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	read <= 1;
+	@(posedge clk);
+	read <= 0;
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+
+	repeat(10)
+	  begin
+	     write <= 1;
+	     @(posedge clk);
+	     write <= 0;
+	     @(posedge clk);
+	     @(posedge clk);
+	     @(posedge clk);
+	     read <= 1;
+	     @(posedge clk);
+	     read <= 0;
+	     @(posedge clk);
+	     @(posedge clk);
+	     @(posedge clk);
+	     @(posedge clk);
+	     @(posedge clk);
+	  end // repeat (10)
+	
+	write <= 1;
+	repeat (4)
+	  @(posedge clk);
+	write <= 0;
+	@(posedge clk);
+	read <= 1;
+	repeat (4)
+	  @(posedge clk);
+	read <= 0;
+	@(posedge clk);
+
+
+	write <= 1;
+	repeat (4)
+	  @(posedge clk);
+	write <= 0;
+	@(posedge clk);
+	repeat (4)
+	  begin
+	     read <= 1;
+	     @(posedge clk);
+	     read <= 0;
+	     @(posedge clk);
+	  end
+
+	write <= 1;
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	@(posedge clk);
+	read <= 1;
+	repeat (5)
+	  @(posedge clk);
+	write <= 0;
+	  @(posedge clk);
+	  @(posedge clk);
+	read <= 0;
+	@(posedge clk);
+
+	write <= 1;
+	repeat (16)
+	  @(posedge clk);
+	write <= 0;
+	@(posedge clk);
+	
+	read <= 1;
+	repeat (16)
+	  @(posedge clk);
+	read <= 0;
+	@(posedge clk);
+		 
+	repeat (10)
+	  @(posedge clk);
+	$finish;
+     end
+endmodule // longfifo_tb