Squashed B200 FPGA Source. Code from Josh Blum, Ian Buckley, and Matt Ettus.

1 files changed, 38 insertions, 0 deletions

diff --git a/fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v b/fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v
new file mode 100644
index 000000000..1df69d449
--- /dev/null
+++ b/fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v
@@ -0,0 +1,38 @@
+
+module axi_fifo32_to_fifo64
+  (input clk, input reset, input clear,
+   input [31:0] i_tdata, input [1:0] i_tuser, input i_tlast, input i_tvalid, output i_tready,
+   output [63:0] o_tdata, output [2:0] o_tuser, output o_tlast, output o_tvalid, input o_tready
+   );
+
+   reg [31:0] 	 holding;
+
+   reg 		 state;
+
+   always @(posedge clk)
+     if(reset | clear)
+       state <= 0;
+     else
+       if(i_tvalid & i_tready)
+       case(state)
+	 0 : if(~i_tlast) state <= 1'b1;
+    	 1 : state <= 1'b0;
+	 default : state <= 1'b0;
+       endcase // case (state)
+
+   always @(posedge clk)
+     if(i_tvalid & i_tready)
+       holding <= i_tdata;
+   
+   assign i_tready = (state == 0 && !i_tlast)? 1'b1 : o_tready;
+   assign o_tvalid = (state == 0 && !i_tlast)? 1'b0 : i_tvalid;
+   
+   assign o_tdata = (state == 0) ? {i_tdata, 32'h0} : { holding, i_tdata };
+   assign o_tlast = i_tlast;
+
+   wire [2:0] 	 occ_in = (i_tuser == 0) ? 3'd4 : {1'b0, i_tuser};
+   wire [2:0] 	 occ_out = (state == 0) ? occ_in : (occ_in + 3'd4);
+   
+   assign o_tuser = ~o_tlast ? 3'd0 : occ_out;
+   	 
+endmodule // axi_fifo32_to_fifo64