1 files changed, 37 insertions, 0 deletions
diff --git a/fpga/usrp3/lib/rfnoc/counter.v b/fpga/usrp3/lib/rfnoc/counter.v
new file mode 100644
index 000000000..f3480aaf6
--- /dev/null
+++ b/fpga/usrp3/lib/rfnoc/counter.v
@@ -0,0 +1,37 @@
+//
+// Copyright 2014 Ettus Research LLC
+// Copyright 2018 Ettus Research, a National Instruments Company
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+//
+// Simple counter, reset by i_tlast on input side.  i_tdata not connected
+//  Most useful for indexing a RAM, creating a ramp, etc.
+
+module counter
+  #(parameter WIDTH=16)
+   (input clk, input reset, input clear,
+    input [WIDTH:0] max,
+    input i_tlast, input i_tvalid, output i_tready,
+    output [WIDTH-1:0] o_tdata, output o_tlast, output o_tvalid, input o_tready);
+
+   reg [WIDTH-1:0]     count;
+   
+   wire 	       do_it = o_tready & i_tvalid;
+   wire 	       done = (count >= (max-1));
+   
+   always @(posedge clk)
+     if(reset | clear)
+       count <= 0;
+     else
+       if(do_it)
+	 if( done | i_tlast )
+	   count <= 0;
+   	 else
+	   count <= count + 1;
+   
+   assign o_tdata = count;
+   assign o_tlast = done | i_tlast;
+   assign o_tvalid = i_tvalid;
+   assign i_tready = do_it;
+   
+endmodule // counter