1 files changed, 49 insertions, 0 deletions
diff --git a/fpga/usrp2/control_lib/medfifo.v b/fpga/usrp2/control_lib/medfifo.v
new file mode 100644
index 000000000..5a77e8c16
--- /dev/null
+++ b/fpga/usrp2/control_lib/medfifo.v
@@ -0,0 +1,49 @@
+
+module medfifo
+  #(parameter WIDTH=32,
+    parameter DEPTH=1)
+    (input clk, input rst,
+     input [WIDTH-1:0] datain,
+     output [WIDTH-1:0] dataout,
+     input read,
+     input write,
+     input clear,
+     output full,
+     output empty,
+     output [7:0] space,
+     output [7:0] occupied);
+
+   localparam 		NUM_FIFOS = (1<<DEPTH);
+   
+   wire [WIDTH-1:0] 	dout [0:NUM_FIFOS-1];
+   wire [0:NUM_FIFOS-1] full_x;
+   wire [0:NUM_FIFOS-1] empty_x;
+
+   shortfifo #(.WIDTH(WIDTH))
+     head (.clk(clk),.rst(rst),
+	   .datain(datain),.write(write),.full(full),
+	   .dataout(dout[0]),.read(~empty_x[0] & ~full_x[1]),.empty(empty_x[0]),
+	   .clear(clear),.space(space[4:0]),.occupied() );
+   
+   shortfifo #(.WIDTH(WIDTH))
+     tail (.clk(clk),.rst(rst),
+	   .datain(dout[NUM_FIFOS-2]),.write(~empty_x[NUM_FIFOS-2] & ~full_x[NUM_FIFOS-1]),.full(full_x[NUM_FIFOS-1]),
+	   .dataout(dataout),.read(read),.empty(empty),
+	   .clear(clear),.space(),.occupied(occupied[4:0]) );
+
+   genvar 		i;
+   generate
+      for(i = 1; i < NUM_FIFOS-1 ; i = i + 1)
+	begin : gen_depth
+	   shortfifo #(.WIDTH(WIDTH))
+	     shortfifo (.clk(clk),.rst(rst),
+			.datain(dout[i-1]),.write(~full_x[i] & ~empty_x[i-1]),.full(full_x[i]),
+			.dataout(dout[i]),.read(~full_x[i+1] & ~empty_x[i]),.empty(empty_x[i]),
+			.clear(clear),.space(),.occupied() );
+	end
+   endgenerate
+
+   assign space[7:5] = 0;
+   assign occupied[7:5] = 0;
+   
+endmodule // medfifo