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

Original-commit: 0df4b801a34697f2058b4a7b95e08d2a0576c9db

lib/control/gpio_atr.v

@@ -0,0 +1,64 @@
+
+//
+// Copyright 2011 Ettus Research LLC
+//
+
+
+
+module gpio_atr
+  #(parameter BASE = 0,
+    parameter WIDTH = 32)
+   (input clk, input reset,
+    input set_stb, input [7:0] set_addr, input [31:0] set_data,
+    input rx, input tx,
+    inout [WIDTH-1:0] gpio,
+    output reg [31:0] gpio_readback
+    );
+   
+   wire [WIDTH-1:0]   ddr, in_idle, in_tx, in_rx, in_fdx;
+   reg [WIDTH-1:0]    rgpio, igpio;
+   reg [WIDTH-1:0]    gpio_pipe;
+   
+   
+   setting_reg #(.my_addr(BASE+0), .width(WIDTH)) reg_idle
+     (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr), .in(set_data),
+      .out(in_idle),.changed());
+
+   setting_reg #(.my_addr(BASE+1), .width(WIDTH)) reg_rx
+     (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr), .in(set_data),
+      .out(in_rx),.changed());
+
+   setting_reg #(.my_addr(BASE+2), .width(WIDTH)) reg_tx
+     (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr), .in(set_data),
+      .out(in_tx),.changed());
+
+   setting_reg #(.my_addr(BASE+3), .width(WIDTH)) reg_fdx
+     (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr), .in(set_data),
+      .out(in_fdx),.changed());
+
+   setting_reg #(.my_addr(BASE+4), .width(WIDTH)) reg_ddr
+     (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr), .in(set_data),
+      .out(ddr),.changed());
+
+   always @(posedge clk)
+     case({tx,rx})
+       2'b00: rgpio <= in_idle;
+       2'b01: rgpio <= in_rx;
+       2'b10: rgpio <= in_tx;
+       2'b11: rgpio <= in_fdx;
+     endcase // case ({tx,rx})
+   
+   integer 	      n;
+   always @*
+     for(n=0;n<WIDTH;n=n+1)
+       igpio[n] <= ddr[n] ? rgpio[n] : 1'bz;
+
+   assign     gpio = igpio;
+
+   // Double pipeline stage for timing, first flop is in IOB, second in core logic.
+   always @(posedge clk) begin
+      gpio_pipe <= gpio;
+      gpio_readback <= gpio_pipe;
+   end
+   
+endmodule // gpio_atr