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

13 files changed, 2394 insertions, 0 deletions

diff --git a/fpga/usrp3/lib/wishbone/Makefile.srcs b/fpga/usrp3/lib/wishbone/Makefile.srcs
new file mode 100644
index 000000000..6459de834
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/Makefile.srcs
@@ -0,0 +1,19 @@
+#
+# Copyright 2010-2012 Ettus Research LLC
+#
+
+##################################################
+# Wishbone Perifs
+##################################################
+WISHBONE_SRCS = $(abspath $(addprefix $(BASE_DIR)/../lib/wishbone/, \
+simple_uart_rx.v \
+simple_uart_tx.v \
+simple_uart.v \
+wb_1master.v \
+settings_bus.v \
+settings_readback.v \
+i2c_master_top.v \
+i2c_master_bit_ctrl.v \
+i2c_master_byte_ctrl.v \
+axi_stream_to_wb.v \
+))
diff --git a/fpga/usrp3/lib/wishbone/axi_stream_to_wb.v b/fpga/usrp3/lib/wishbone/axi_stream_to_wb.v
new file mode 100644
index 000000000..a71daf063
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/axi_stream_to_wb.v
@@ -0,0 +1,246 @@
+//
+// Copyright 2012 Ettus Research LLC
+//
+
+
+// AXI stream to/from wishbone
+// Input is an axi stream which wites into a BRAM.
+// Output is an axi stream which reads from a BRAM.
+// This RAM can also be accessed from a wishbone interface.
+
+// From the wishbone interface we need to be able to:
+
+// Ask the module if a completed packet is available.
+// Read number of bytes/lines in the BRAM.
+// Release the completed packet.
+
+// Ask the module if an outgoing slot is available.
+// Write number of bytes/lines in the BRAM.
+// Release the completed packet.
+
+module axi_stream_to_wb
+#(
+    parameter AWIDTH = 13, //WB addr width and buffering size in bytes
+    parameter UWIDTH = 4, //stream user width
+    parameter CTRL_ADDR = 0 //ctrl/status register
+)
+(
+    //-- the wishbone interface
+    input clk_i, input rst_i,
+    input we_i, input stb_i, input cyc_i, output reg ack_o,
+    input [AWIDTH-1:0] adr_i, input [31:0] dat_i, output [31:0] dat_o,
+
+    //-- the axi stream interface input
+    input [63:0] rx_tdata,
+    input [3:0] rx_tuser,
+    input rx_tlast,
+    input rx_tvalid,
+    output rx_tready,
+
+    //-- the axi stream interface output
+    output [63:0] tx_tdata,
+    output [3:0] tx_tuser,
+    output tx_tlast,
+    output tx_tvalid,
+    input tx_tready,
+
+    output [31:0] debug_rx,
+    output [31:0] debug_tx
+);
+
+    //drive the ack signal
+    always @(posedge clk_i) begin
+        if (rst_i) ack_o <= 0;
+        else ack_o <= stb_i & ~ack_o;
+    end
+
+    //control registers, status
+    reg [AWIDTH-1:0] tx_bytes, rx_bytes;
+    reg tx_error, rx_error;
+    wire rx_state_flag, tx_state_flag;
+    reg rx_proc_flag, tx_proc_flag;
+
+    //assign status
+    wire [31:0] status;
+    assign status[31] = rx_state_flag;
+    assign status[30] = tx_state_flag;
+    assign status[29] = rx_error;
+    assign status[AWIDTH-1:0] = rx_bytes;
+
+   // Create some piplining to break timing paths.
+   reg 		ctrl_addressed;
+   always @(posedge clk_i)
+     if (rst_i)
+       ctrl_addressed <= 1'b0;
+     else if(adr_i == CTRL_ADDR)
+       ctrl_addressed <= 1'b1;
+     else
+       ctrl_addressed <= 1'b0;
+       
+    //assign control
+    always @(posedge clk_i) begin
+        if (rst_i) begin
+            rx_proc_flag <= 0;
+            tx_proc_flag <= 0;
+            tx_error <= 0;
+            tx_bytes <= 0;
+        end
+        else if (we_i && ack_o && ctrl_addressed) begin
+            rx_proc_flag <= dat_i[31];
+            tx_proc_flag <= dat_i[30];
+            tx_error <= dat_i[29];
+            tx_bytes <= dat_i[AWIDTH-1:0];
+        end
+    end
+
+    //------------------------------------------------------------------
+    //-- block ram interface between wb and input stream
+    //------------------------------------------------------------------
+    reg [AWIDTH-4:0] rx_counter;
+    wire [63:0] rx_bram_data64;
+    ram_2port #(.DWIDTH(64), .AWIDTH(AWIDTH-3)) input_stream_bram
+    (
+        .clka(clk_i), .ena(rx_tready), .wea(rx_tvalid),
+        .addra(rx_counter), .dia(rx_tdata), .doa(),
+        .clkb(clk_i), .enb(stb_i), .web(1'b0),
+        .addrb(adr_i[AWIDTH-1:3]), .dib({64{1'b1}}), .dob(rx_bram_data64)
+    );
+
+    //select the data source, status, or upper/lower 32 from bram
+    assign dat_o = ctrl_addressed ? status : ((!adr_i[2])? rx_bram_data64[63:32]: rx_bram_data64[31:0]);
+
+    //------------------------------------------------------------------
+    //-- block ram interface between wb and output stream
+    //------------------------------------------------------------------
+    reg [AWIDTH-4:0] tx_counter;
+    wire enb_out;
+    wire [63:0] tx_bram_data64;
+    ram_2port #(.DWIDTH(64), .AWIDTH(AWIDTH-3)) output_stream_bram
+    (
+        .clka(clk_i), .ena(enb_out), .wea(1'b0),
+        .addra(tx_counter), .dia({64{1'b1}}), .doa(tx_tdata),
+        .clkb(clk_i), .enb(stb_i), .web(we_i && adr_i[2]),
+        .addrb(adr_i[AWIDTH-1:3]), .dib(tx_bram_data64), .dob()
+    );
+
+    //write 64 bit chunks, so register the lower write
+    reg [31:0] dat_i_reg;
+    always @(posedge clk_i) begin
+        if (we_i && stb_i && !adr_i[2]) dat_i_reg <= dat_i;
+    end
+    assign tx_bram_data64 = {dat_i_reg, dat_i};
+
+    //------------------------------------------------------------------
+    //-- state machine to drive input stream
+    //------------------------------------------------------------------
+    localparam RX_STATE_READY = 0; //waits for proc flag 0
+    localparam RX_STATE_WRITE = 1; //writes stream to bram
+    localparam RX_STATE_RELEASE = 2; //waits for proc to flag 1
+    reg [1:0] rx_state;
+
+    always @(posedge clk_i) begin
+        if (rst_i) begin
+            rx_state <= RX_STATE_READY;
+            rx_counter <= 0;
+            rx_error <= 0;
+            rx_bytes <= 0;
+        end
+        else case (rx_state)
+
+        RX_STATE_READY: begin
+            if (!rx_proc_flag) rx_state <= RX_STATE_WRITE;
+            rx_counter <= 0;
+        end
+
+        RX_STATE_WRITE: begin
+            if (rx_tready && rx_tvalid) begin
+                rx_counter <= rx_counter + 1'b1;
+                if (rx_tlast) begin
+                    rx_state <= RX_STATE_RELEASE;
+                    rx_bytes <= {rx_counter + 1'b1, rx_tuser[2:0]};
+                    rx_error <= rx_tuser[3];
+                end
+            end
+        end
+
+        RX_STATE_RELEASE: begin
+            if (rx_proc_flag) rx_state <= RX_STATE_READY;
+            rx_counter <= 0;
+        end
+
+        default: rx_state <= RX_STATE_READY;
+        endcase //rx_state
+    end
+
+    //flag tells the processor when it can grab some input buffer
+    assign rx_state_flag = (rx_state == RX_STATE_RELEASE);
+
+    //always ready to accept input data in the write state
+    assign rx_tready = (rx_state == RX_STATE_WRITE);
+
+    //------------------------------------------------------------------
+    //-- state machine to drive output stream
+    //------------------------------------------------------------------
+    localparam TX_STATE_READY = 0;  //waits for proc flag 0
+    localparam TX_STATE_WRITE = 1; //writes bram to stream
+    localparam TX_STATE_RELEASE = 2; //waits for proc to flag 1
+    reg [1:0] tx_state;
+
+    always @(posedge clk_i) begin
+        if (rst_i) begin
+            tx_state <= TX_STATE_READY;
+            tx_counter <= 0;
+        end
+        else case (tx_state)
+
+        TX_STATE_READY: begin
+            if (tx_proc_flag) begin
+                tx_state <= TX_STATE_WRITE;
+                tx_counter <= 1;
+            end
+            else tx_counter <= 0;
+        end
+
+        TX_STATE_WRITE: begin
+            if (tx_tready && tx_tvalid) begin
+                tx_counter <= tx_counter + 1'b1;
+                if (tx_tlast) begin
+                    tx_state <= TX_STATE_RELEASE;
+                end
+            end
+        end
+
+        TX_STATE_RELEASE: begin
+            if (!tx_proc_flag) tx_state <= TX_STATE_READY;
+            tx_counter <= 0;
+        end
+
+        default: tx_state <= TX_STATE_READY;
+        endcase //tx_state
+    end
+
+    //flag tells the processor when it can grab available out buffer
+    assign tx_state_flag = (tx_state == TX_STATE_READY);
+
+    //the output user bus assignment (non-zero only at end)
+    assign tx_tuser = (tx_tlast)? {tx_error, tx_bytes[2:0]} : 4'b0;
+
+    //end of frame signal
+    assign tx_tlast = (tx_counter == tx_bytes[AWIDTH-1:3]);
+
+    //output is always valid in state write
+    assign tx_tvalid = (tx_state == TX_STATE_WRITE);
+
+    //enable the read so we can pre-read due to read 1 cycle delay
+    assign enb_out = (tx_state == TX_STATE_WRITE)? (tx_tvalid && tx_tready) : 1'b1;
+
+    assign debug_rx = {
+        rx_state, rx_tlast, rx_tvalid, rx_tready, rx_tuser[2:0], //8
+        rx_proc_flag, rx_state_flag, rx_tdata[21:0] //24
+    };
+    assign debug_tx = {
+        tx_state, tx_tlast, tx_tvalid, tx_tready, tx_tuser[2:0], //8
+        tx_proc_flag, tx_state_flag, tx_tdata[21:0] //24
+    };
+
+endmodule //axi_stream_to_wb
diff --git a/fpga/usrp3/lib/wishbone/i2c_master_bit_ctrl.v b/fpga/usrp3/lib/wishbone/i2c_master_bit_ctrl.v
new file mode 100644
index 000000000..68ec27004
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/i2c_master_bit_ctrl.v
@@ -0,0 +1,538 @@
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+////  WISHBONE rev.B2 compliant I2C Master bit-controller        ////
+////                                                             ////
+////                                                             ////
+////  Author: Richard Herveille                                  ////
+////          richard@asics.ws                                   ////
+////          www.asics.ws                                       ////
+////                                                             ////
+////  Downloaded from: http://www.opencores.org/projects/i2c/    ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+//// Copyright (C) 2001 Richard Herveille                        ////
+////                    richard@asics.ws                         ////
+////                                                             ////
+//// This source file may be used and distributed without        ////
+//// restriction provided that this copyright statement is not   ////
+//// removed from the file and that any derivative work contains ////
+//// the original copyright notice and the associated disclaimer.////
+////                                                             ////
+////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////
+//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////
+//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////
+//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////
+//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////
+//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////
+//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////
+//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////
+//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////
+//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////
+//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////
+//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////
+//// POSSIBILITY OF SUCH DAMAGE.                                 ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+
+//  CVS Log
+//
+//  $Id: i2c_master_bit_ctrl.v,v 1.12 2006/09/04 09:08:13 rherveille Exp $
+//
+//  $Date: 2006/09/04 09:08:13 $
+//  $Revision: 1.12 $
+//  $Author: rherveille $
+//  $Locker:  $
+//  $State: Exp $
+//
+// Change History:
+//               $Log: i2c_master_bit_ctrl.v,v $
+//               Revision 1.12  2006/09/04 09:08:13  rherveille
+//               fixed short scl high pulse after clock stretch
+//               fixed slave model not returning correct '(n)ack' signal
+//
+//               Revision 1.11  2004/05/07 11:02:26  rherveille
+//               Fixed a bug where the core would signal an arbitration lost (AL bit set), when another master controls the bus and the other master generates a STOP bit.
+//
+//               Revision 1.10  2003/08/09 07:01:33  rherveille
+//               Fixed a bug in the Arbitration Lost generation caused by delay on the (external) sda line.
+//               Fixed a potential bug in the byte controller's host-acknowledge generation.
+//
+//               Revision 1.9  2003/03/10 14:26:37  rherveille
+//               Fixed cmd_ack generation item (no bug).
+//
+//               Revision 1.8  2003/02/05 00:06:10  rherveille
+//               Fixed a bug where the core would trigger an erroneous 'arbitration lost' interrupt after being reset, when the reset pulse width < 3 clk cycles.
+//
+//               Revision 1.7  2002/12/26 16:05:12  rherveille
+//               Small code simplifications
+//
+//               Revision 1.6  2002/12/26 15:02:32  rherveille
+//               Core is now a Multimaster I2C controller
+//
+//               Revision 1.5  2002/11/30 22:24:40  rherveille
+//               Cleaned up code
+//
+//               Revision 1.4  2002/10/30 18:10:07  rherveille
+//               Fixed some reported minor start/stop generation timing issuess.
+//
+//               Revision 1.3  2002/06/15 07:37:03  rherveille
+//               Fixed a small timing bug in the bit controller.\nAdded verilog simulation environment.
+//
+//               Revision 1.2  2001/11/05 11:59:25  rherveille
+//               Fixed wb_ack_o generation bug.
+//               Fixed bug in the byte_controller statemachine.
+//               Added headers.
+//
+
+//
+/////////////////////////////////////
+// Bit controller section
+/////////////////////////////////////
+//
+// Translate simple commands into SCL/SDA transitions
+// Each command has 5 states, A/B/C/D/idle
+//
+// start:	SCL	~~~~~~~~~~\____
+//	SDA	~~~~~~~~\______
+//		 x | A | B | C | D | i
+//
+// repstart	SCL	____/~~~~\___
+//	SDA	__/~~~\______
+//		 x | A | B | C | D | i
+//
+// stop	SCL	____/~~~~~~~~
+//	SDA	==\____/~~~~~
+//		 x | A | B | C | D | i
+//
+//- write	SCL	____/~~~~\____
+//	SDA	==X=========X=
+//		 x | A | B | C | D | i
+//
+//- read	SCL	____/~~~~\____
+//	SDA	XXXX=====XXXX
+//		 x | A | B | C | D | i
+//
+
+// Timing:     Normal mode      Fast mode
+///////////////////////////////////////////////////////////////////////
+// Fscl        100KHz           400KHz
+// Th_scl      4.0us            0.6us   High period of SCL
+// Tl_scl      4.7us            1.3us   Low period of SCL
+// Tsu:sta     4.7us            0.6us   setup time for a repeated start condition
+// Tsu:sto     4.0us            0.6us   setup time for a stop conditon
+// Tbuf        4.7us            1.3us   Bus free time between a stop and start condition
+//
+
+// synopsys translate_off
+//`include "timescale.v"
+// synopsys translate_on
+
+`include "i2c_master_defines.v"
+
+module i2c_master_bit_ctrl(
+	clk, rst, nReset, 
+	clk_cnt, ena, cmd, cmd_ack, busy, al, din, dout,
+	scl_i, scl_o, scl_oen, sda_i, sda_o, sda_oen
+	);
+
+	//
+	// inputs & outputs
+	//
+	input clk;
+	input rst;
+	input nReset;
+	input ena;            // core enable signal
+
+	input [15:0] clk_cnt; // clock prescale value
+
+	input  [3:0] cmd;
+	output       cmd_ack; // command complete acknowledge
+	reg cmd_ack;
+	output       busy;    // i2c bus busy
+	reg busy;
+	output       al;      // i2c bus arbitration lost
+	reg al;
+
+	input  din;
+	output dout;
+	reg dout;
+
+	// I2C lines
+	input  scl_i;         // i2c clock line input
+	output scl_o;         // i2c clock line output
+	output scl_oen;       // i2c clock line output enable (active low)
+	reg scl_oen;
+	input  sda_i;         // i2c data line input
+	output sda_o;         // i2c data line output
+	output sda_oen;       // i2c data line output enable (active low)
+	reg sda_oen;
+
+
+	//
+	// variable declarations
+	//
+
+	reg sSCL, sSDA;             // synchronized SCL and SDA inputs
+	reg dscl_oen;               // delayed scl_oen
+	reg sda_chk;                // check SDA output (Multi-master arbitration)
+	reg clk_en;                 // clock generation signals
+	wire slave_wait;
+//	reg [15:0] cnt = clk_cnt;   // clock divider counter (simulation)
+	reg [15:0] cnt;             // clock divider counter (synthesis)
+
+	// state machine variable
+	reg [16:0] c_state; // synopsys enum_state
+
+	//
+	// module body
+	//
+
+	// whenever the slave is not ready it can delay the cycle by pulling SCL low
+	// delay scl_oen
+	always @(posedge clk)
+	  dscl_oen <= #1 scl_oen;
+
+	assign slave_wait = dscl_oen && !sSCL;
+
+
+	// generate clk enable signal
+	always @(posedge clk or negedge nReset)
+	  if(~nReset)
+	    begin
+	        cnt    <= #1 16'h0;
+	        clk_en <= #1 1'b1;
+	    end
+	  else if (rst)
+	    begin
+	        cnt    <= #1 16'h0;
+	        clk_en <= #1 1'b1;
+	    end
+	  else if ( ~|cnt || !ena)
+	    begin
+	        cnt    <= #1 clk_cnt;
+	        clk_en <= #1 1'b1;
+	    end
+	  else if (slave_wait)
+	    begin
+	        cnt    <= #1 cnt;
+	        clk_en <= #1 1'b0;    
+	    end
+	  else
+	    begin
+	        cnt    <= #1 cnt - 16'h1;
+	        clk_en <= #1 1'b0;
+	    end
+
+
+	// generate bus status controller
+	reg dSCL, dSDA;
+	reg sta_condition;
+	reg sto_condition;
+
+	// synchronize SCL and SDA inputs
+	// reduce metastability risc
+	always @(posedge clk or negedge nReset)
+	  if (~nReset)
+	    begin
+	        sSCL <= #1 1'b1;
+	        sSDA <= #1 1'b1;
+
+	        dSCL <= #1 1'b1;
+	        dSDA <= #1 1'b1;
+	    end
+	  else if (rst)
+	    begin
+	        sSCL <= #1 1'b1;
+	        sSDA <= #1 1'b1;
+
+	        dSCL <= #1 1'b1;
+	        dSDA <= #1 1'b1;
+	    end
+	  else
+	    begin
+	        sSCL <= #1 scl_i;
+	        sSDA <= #1 sda_i;
+
+	        dSCL <= #1 sSCL;
+	        dSDA <= #1 sSDA;
+	    end
+
+	// detect start condition => detect falling edge on SDA while SCL is high
+	// detect stop condition => detect rising edge on SDA while SCL is high
+	always @(posedge clk or negedge nReset)
+	  if (~nReset)
+	    begin
+	        sta_condition <= #1 1'b0;
+	        sto_condition <= #1 1'b0;
+	    end
+	  else if (rst)
+	    begin
+	        sta_condition <= #1 1'b0;
+	        sto_condition <= #1 1'b0;
+	    end
+	  else
+	    begin
+	        sta_condition <= #1 ~sSDA &  dSDA & sSCL;
+	        sto_condition <= #1  sSDA & ~dSDA & sSCL;
+	    end
+
+	// generate i2c bus busy signal
+	always @(posedge clk or negedge nReset)
+	  if(!nReset)
+	    busy <= #1 1'b0;
+	  else if (rst)
+	    busy <= #1 1'b0;
+	  else
+	    busy <= #1 (sta_condition | busy) & ~sto_condition;
+
+	// generate arbitration lost signal
+	// aribitration lost when:
+	// 1) master drives SDA high, but the i2c bus is low
+	// 2) stop detected while not requested
+	reg cmd_stop;
+	always @(posedge clk or negedge nReset)
+	  if (~nReset)
+	    cmd_stop <= #1 1'b0;
+	  else if (rst)
+	    cmd_stop <= #1 1'b0;
+	  else if (clk_en)
+	    cmd_stop <= #1 cmd == `I2C_CMD_STOP;
+
+	always @(posedge clk or negedge nReset)
+	  if (~nReset)
+	    al <= #1 1'b0;
+	  else if (rst)
+	    al <= #1 1'b0;
+	  else
+	    al <= #1 (sda_chk & ~sSDA & sda_oen) | (|c_state & sto_condition & ~cmd_stop);
+
+
+	// generate dout signal (store SDA on rising edge of SCL)
+	always @(posedge clk)
+	  if(sSCL & ~dSCL)
+	    dout <= #1 sSDA;
+
+	// generate statemachine
+
+	// nxt_state decoder
+	parameter [16:0] idle    = 17'b0_0000_0000_0000_0000;
+	parameter [16:0] start_a = 17'b0_0000_0000_0000_0001;
+	parameter [16:0] start_b = 17'b0_0000_0000_0000_0010;
+	parameter [16:0] start_c = 17'b0_0000_0000_0000_0100;
+	parameter [16:0] start_d = 17'b0_0000_0000_0000_1000;
+	parameter [16:0] start_e = 17'b0_0000_0000_0001_0000;
+	parameter [16:0] stop_a  = 17'b0_0000_0000_0010_0000;
+	parameter [16:0] stop_b  = 17'b0_0000_0000_0100_0000;
+	parameter [16:0] stop_c  = 17'b0_0000_0000_1000_0000;
+	parameter [16:0] stop_d  = 17'b0_0000_0001_0000_0000;
+	parameter [16:0] rd_a    = 17'b0_0000_0010_0000_0000;
+	parameter [16:0] rd_b    = 17'b0_0000_0100_0000_0000;
+	parameter [16:0] rd_c    = 17'b0_0000_1000_0000_0000;
+	parameter [16:0] rd_d    = 17'b0_0001_0000_0000_0000;
+	parameter [16:0] wr_a    = 17'b0_0010_0000_0000_0000;
+	parameter [16:0] wr_b    = 17'b0_0100_0000_0000_0000;
+	parameter [16:0] wr_c    = 17'b0_1000_0000_0000_0000;
+	parameter [16:0] wr_d    = 17'b1_0000_0000_0000_0000;
+
+	always @(posedge clk or negedge nReset)
+	  if (!nReset)
+	    begin
+	        c_state <= #1 idle;
+	        cmd_ack <= #1 1'b0;
+	        scl_oen <= #1 1'b1;
+	        sda_oen <= #1 1'b1;
+	        sda_chk <= #1 1'b0;
+	    end
+	  else if (rst | al)
+	    begin
+	        c_state <= #1 idle;
+	        cmd_ack <= #1 1'b0;
+	        scl_oen <= #1 1'b1;
+	        sda_oen <= #1 1'b1;
+	        sda_chk <= #1 1'b0;
+	    end
+	  else
+	    begin
+	        cmd_ack   <= #1 1'b0; // default no command acknowledge + assert cmd_ack only 1clk cycle
+
+	        if (clk_en)
+	          case (c_state) // synopsys full_case parallel_case
+	            // idle state
+	            idle:
+	            begin
+	                case (cmd) // synopsys full_case parallel_case
+	                  `I2C_CMD_START:
+	                     c_state <= #1 start_a;
+
+	                  `I2C_CMD_STOP:
+	                     c_state <= #1 stop_a;
+
+	                  `I2C_CMD_WRITE:
+	                     c_state <= #1 wr_a;
+
+	                  `I2C_CMD_READ:
+	                     c_state <= #1 rd_a;
+
+	                  default:
+	                    c_state <= #1 idle;
+	                endcase
+
+	                scl_oen <= #1 scl_oen; // keep SCL in same state
+	                sda_oen <= #1 sda_oen; // keep SDA in same state
+	                sda_chk <= #1 1'b0;    // don't check SDA output
+	            end
+
+	            // start
+	            start_a:
+	            begin
+	                c_state <= #1 start_b;
+	                scl_oen <= #1 scl_oen; // keep SCL in same state
+	                sda_oen <= #1 1'b1;    // set SDA high
+	                sda_chk <= #1 1'b0;    // don't check SDA output
+	            end
+
+	            start_b:
+	            begin
+	                c_state <= #1 start_c;
+	                scl_oen <= #1 1'b1; // set SCL high
+	                sda_oen <= #1 1'b1; // keep SDA high
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            start_c:
+	            begin
+	                c_state <= #1 start_d;
+	                scl_oen <= #1 1'b1; // keep SCL high
+	                sda_oen <= #1 1'b0; // set SDA low
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            start_d:
+	            begin
+	                c_state <= #1 start_e;
+	                scl_oen <= #1 1'b1; // keep SCL high
+	                sda_oen <= #1 1'b0; // keep SDA low
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            start_e:
+	            begin
+	                c_state <= #1 idle;
+	                cmd_ack <= #1 1'b1;
+	                scl_oen <= #1 1'b0; // set SCL low
+	                sda_oen <= #1 1'b0; // keep SDA low
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            // stop
+	            stop_a:
+	            begin
+	                c_state <= #1 stop_b;
+	                scl_oen <= #1 1'b0; // keep SCL low
+	                sda_oen <= #1 1'b0; // set SDA low
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            stop_b:
+	            begin
+	                c_state <= #1 stop_c;
+	                scl_oen <= #1 1'b1; // set SCL high
+	                sda_oen <= #1 1'b0; // keep SDA low
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            stop_c:
+	            begin
+	                c_state <= #1 stop_d;
+	                scl_oen <= #1 1'b1; // keep SCL high
+	                sda_oen <= #1 1'b0; // keep SDA low
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            stop_d:
+	            begin
+	                c_state <= #1 idle;
+	                cmd_ack <= #1 1'b1;
+	                scl_oen <= #1 1'b1; // keep SCL high
+	                sda_oen <= #1 1'b1; // set SDA high
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            // read
+	            rd_a:
+	            begin
+	                c_state <= #1 rd_b;
+	                scl_oen <= #1 1'b0; // keep SCL low
+	                sda_oen <= #1 1'b1; // tri-state SDA
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            rd_b:
+	            begin
+	                c_state <= #1 rd_c;
+	                scl_oen <= #1 1'b1; // set SCL high
+	                sda_oen <= #1 1'b1; // keep SDA tri-stated
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            rd_c:
+	            begin
+	                c_state <= #1 rd_d;
+	                scl_oen <= #1 1'b1; // keep SCL high
+	                sda_oen <= #1 1'b1; // keep SDA tri-stated
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            rd_d:
+	            begin
+	                c_state <= #1 idle;
+	                cmd_ack <= #1 1'b1;
+	                scl_oen <= #1 1'b0; // set SCL low
+	                sda_oen <= #1 1'b1; // keep SDA tri-stated
+	                sda_chk <= #1 1'b0; // don't check SDA output
+	            end
+
+	            // write
+	            wr_a:
+	            begin
+	                c_state <= #1 wr_b;
+	                scl_oen <= #1 1'b0; // keep SCL low
+	                sda_oen <= #1 din;  // set SDA
+	                sda_chk <= #1 1'b0; // don't check SDA output (SCL low)
+	            end
+
+	            wr_b:
+	            begin
+	                c_state <= #1 wr_c;
+	                scl_oen <= #1 1'b1; // set SCL high
+	                sda_oen <= #1 din;  // keep SDA
+	                sda_chk <= #1 1'b1; // check SDA output
+	            end
+
+	            wr_c:
+	            begin
+	                c_state <= #1 wr_d;
+	                scl_oen <= #1 1'b1; // keep SCL high
+	                sda_oen <= #1 din;
+	                sda_chk <= #1 1'b1; // check SDA output
+	            end
+
+	            wr_d:
+	            begin
+	                c_state <= #1 idle;
+	                cmd_ack <= #1 1'b1;
+	                scl_oen <= #1 1'b0; // set SCL low
+	                sda_oen <= #1 din;
+	                sda_chk <= #1 1'b0; // don't check SDA output (SCL low)
+	            end
+
+	          endcase
+	    end
+
+
+	// assign scl and sda output (always gnd)
+	assign scl_o = 1'b0;
+	assign sda_o = 1'b0;
+
+endmodule
diff --git a/fpga/usrp3/lib/wishbone/i2c_master_byte_ctrl.v b/fpga/usrp3/lib/wishbone/i2c_master_byte_ctrl.v
new file mode 100644
index 000000000..784b58188
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/i2c_master_byte_ctrl.v
@@ -0,0 +1,344 @@
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+////  WISHBONE rev.B2 compliant I2C Master byte-controller       ////
+////                                                             ////
+////                                                             ////
+////  Author: Richard Herveille                                  ////
+////          richard@asics.ws                                   ////
+////          www.asics.ws                                       ////
+////                                                             ////
+////  Downloaded from: http://www.opencores.org/projects/i2c/    ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+//// Copyright (C) 2001 Richard Herveille                        ////
+////                    richard@asics.ws                         ////
+////                                                             ////
+//// This source file may be used and distributed without        ////
+//// restriction provided that this copyright statement is not   ////
+//// removed from the file and that any derivative work contains ////
+//// the original copyright notice and the associated disclaimer.////
+////                                                             ////
+////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////
+//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////
+//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////
+//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////
+//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////
+//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////
+//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////
+//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////
+//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////
+//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////
+//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////
+//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////
+//// POSSIBILITY OF SUCH DAMAGE.                                 ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+
+//  CVS Log
+//
+//  $Id: i2c_master_byte_ctrl.v,v 1.7 2004/02/18 11:40:46 rherveille Exp $
+//
+//  $Date: 2004/02/18 11:40:46 $
+//  $Revision: 1.7 $
+//  $Author: rherveille $
+//  $Locker:  $
+//  $State: Exp $
+//
+// Change History:
+//               $Log: i2c_master_byte_ctrl.v,v $
+//               Revision 1.7  2004/02/18 11:40:46  rherveille
+//               Fixed a potential bug in the statemachine. During a 'stop' 2 cmd_ack signals were generated. Possibly canceling a new start command.
+//
+//               Revision 1.6  2003/08/09 07:01:33  rherveille
+//               Fixed a bug in the Arbitration Lost generation caused by delay on the (external) sda line.
+//               Fixed a potential bug in the byte controller's host-acknowledge generation.
+//
+//               Revision 1.5  2002/12/26 15:02:32  rherveille
+//               Core is now a Multimaster I2C controller
+//
+//               Revision 1.4  2002/11/30 22:24:40  rherveille
+//               Cleaned up code
+//
+//               Revision 1.3  2001/11/05 11:59:25  rherveille
+//               Fixed wb_ack_o generation bug.
+//               Fixed bug in the byte_controller statemachine.
+//               Added headers.
+//
+
+// synopsys translate_off
+//`include "timescale.v"
+// synopsys translate_on
+
+`include "i2c_master_defines.v"
+
+module i2c_master_byte_ctrl (
+	clk, rst, nReset, ena, clk_cnt, start, stop, read, write, ack_in, din,
+	cmd_ack, ack_out, dout, i2c_busy, i2c_al, scl_i, scl_o, scl_oen, sda_i, sda_o, sda_oen );
+
+	//
+	// inputs & outputs
+	//
+	input clk;     // master clock
+	input rst;     // synchronous active high reset
+	input nReset;  // asynchronous active low reset
+	input ena;     // core enable signal
+
+	input [15:0] clk_cnt; // 4x SCL
+
+	// control inputs
+	input       start;
+	input       stop;
+	input       read;
+	input       write;
+	input       ack_in;
+	input [7:0] din;
+
+	// status outputs
+	output       cmd_ack;
+	reg cmd_ack;
+	output       ack_out;
+	reg ack_out;
+	output       i2c_busy;
+	output       i2c_al;
+	output [7:0] dout;
+
+	// I2C signals
+	input  scl_i;
+	output scl_o;
+	output scl_oen;
+	input  sda_i;
+	output sda_o;
+	output sda_oen;
+
+
+	//
+	// Variable declarations
+	//
+
+	// statemachine
+	parameter [4:0] ST_IDLE  = 5'b0_0000;
+	parameter [4:0] ST_START = 5'b0_0001;
+	parameter [4:0] ST_READ  = 5'b0_0010;
+	parameter [4:0] ST_WRITE = 5'b0_0100;
+	parameter [4:0] ST_ACK   = 5'b0_1000;
+	parameter [4:0] ST_STOP  = 5'b1_0000;
+
+	// signals for bit_controller
+	reg  [3:0] core_cmd;
+	reg        core_txd;
+	wire       core_ack, core_rxd;
+
+	// signals for shift register
+	reg [7:0] sr; //8bit shift register
+	reg       shift, ld;
+
+	// signals for state machine
+	wire       go;
+	reg  [2:0] dcnt;
+	wire       cnt_done;
+
+	//
+	// Module body
+	//
+
+	// hookup bit_controller
+	i2c_master_bit_ctrl bit_controller (
+		.clk     ( clk      ),
+		.rst     ( rst      ),
+		.nReset  ( nReset   ),
+		.ena     ( ena      ),
+		.clk_cnt ( clk_cnt  ),
+		.cmd     ( core_cmd ),
+		.cmd_ack ( core_ack ),
+		.busy    ( i2c_busy ),
+		.al      ( i2c_al   ),
+		.din     ( core_txd ),
+		.dout    ( core_rxd ),
+		.scl_i   ( scl_i    ),
+		.scl_o   ( scl_o    ),
+		.scl_oen ( scl_oen  ),
+		.sda_i   ( sda_i    ),
+		.sda_o   ( sda_o    ),
+		.sda_oen ( sda_oen  )
+	);
+
+	// generate go-signal
+	assign go = (read | write | stop) & ~cmd_ack;
+
+	// assign dout output to shift-register
+	assign dout = sr;
+
+	// generate shift register
+	always @(posedge clk or negedge nReset)
+	  if (!nReset)
+	    sr <= #1 8'h0;
+	  else if (rst)
+	    sr <= #1 8'h0;
+	  else if (ld)
+	    sr <= #1 din;
+	  else if (shift)
+	    sr <= #1 {sr[6:0], core_rxd};
+
+	// generate counter
+	always @(posedge clk or negedge nReset)
+	  if (!nReset)
+	    dcnt <= #1 3'h0;
+	  else if (rst)
+	    dcnt <= #1 3'h0;
+	  else if (ld)
+	    dcnt <= #1 3'h7;
+	  else if (shift)
+	    dcnt <= #1 dcnt - 3'h1;
+
+	assign cnt_done = ~(|dcnt);
+
+	//
+	// state machine
+	//
+	reg [4:0] c_state; // synopsis enum_state
+
+	always @(posedge clk or negedge nReset)
+	  if (!nReset)
+	    begin
+	        core_cmd <= #1 `I2C_CMD_NOP;
+	        core_txd <= #1 1'b0;
+	        shift    <= #1 1'b0;
+	        ld       <= #1 1'b0;
+	        cmd_ack  <= #1 1'b0;
+	        c_state  <= #1 ST_IDLE;
+	        ack_out  <= #1 1'b0;
+	    end
+	  else if (rst | i2c_al)
+	   begin
+	       core_cmd <= #1 `I2C_CMD_NOP;
+	       core_txd <= #1 1'b0;
+	       shift    <= #1 1'b0;
+	       ld       <= #1 1'b0;
+	       cmd_ack  <= #1 1'b0;
+	       c_state  <= #1 ST_IDLE;
+	       ack_out  <= #1 1'b0;
+	   end
+	else
+	  begin
+	      // initially reset all signals
+	      core_txd <= #1 sr[7];
+	      shift    <= #1 1'b0;
+	      ld       <= #1 1'b0;
+	      cmd_ack  <= #1 1'b0;
+
+	      case (c_state) // synopsys full_case parallel_case
+	        ST_IDLE:
+	          if (go)
+	            begin
+	                if (start)
+	                  begin
+	                      c_state  <= #1 ST_START;
+	                      core_cmd <= #1 `I2C_CMD_START;
+	                  end
+	                else if (read)
+	                  begin
+	                      c_state  <= #1 ST_READ;
+	                      core_cmd <= #1 `I2C_CMD_READ;
+	                  end
+	                else if (write)
+	                  begin
+	                      c_state  <= #1 ST_WRITE;
+	                      core_cmd <= #1 `I2C_CMD_WRITE;
+	                  end
+	                else // stop
+	                  begin
+	                      c_state  <= #1 ST_STOP;
+	                      core_cmd <= #1 `I2C_CMD_STOP;
+	                  end
+
+	                ld <= #1 1'b1;
+	            end
+
+	        ST_START:
+	          if (core_ack)
+	            begin
+	                if (read)
+	                  begin
+	                      c_state  <= #1 ST_READ;
+	                      core_cmd <= #1 `I2C_CMD_READ;
+	                  end
+	                else
+	                  begin
+	                      c_state  <= #1 ST_WRITE;
+	                      core_cmd <= #1 `I2C_CMD_WRITE;
+	                  end
+
+	                ld <= #1 1'b1;
+	            end
+
+	        ST_WRITE:
+	          if (core_ack)
+	            if (cnt_done)
+	              begin
+	                  c_state  <= #1 ST_ACK;
+	                  core_cmd <= #1 `I2C_CMD_READ;
+	              end
+	            else
+	              begin
+	                  c_state  <= #1 ST_WRITE;       // stay in same state
+	                  core_cmd <= #1 `I2C_CMD_WRITE; // write next bit
+	                  shift    <= #1 1'b1;
+	              end
+
+	        ST_READ:
+	          if (core_ack)
+	            begin
+	                if (cnt_done)
+	                  begin
+	                      c_state  <= #1 ST_ACK;
+	                      core_cmd <= #1 `I2C_CMD_WRITE;
+	                  end
+	                else
+	                  begin
+	                      c_state  <= #1 ST_READ;       // stay in same state
+	                      core_cmd <= #1 `I2C_CMD_READ; // read next bit
+	                  end
+
+	                shift    <= #1 1'b1;
+	                core_txd <= #1 ack_in;
+	            end
+
+	        ST_ACK:
+	          if (core_ack)
+	            begin
+	               if (stop)
+	                 begin
+	                     c_state  <= #1 ST_STOP;
+	                     core_cmd <= #1 `I2C_CMD_STOP;
+	                 end
+	               else
+	                 begin
+	                     c_state  <= #1 ST_IDLE;
+	                     core_cmd <= #1 `I2C_CMD_NOP;
+
+	                     // generate command acknowledge signal
+	                     cmd_ack  <= #1 1'b1;
+	                 end
+
+	                 // assign ack_out output to bit_controller_rxd (contains last received bit)
+	                 ack_out <= #1 core_rxd;
+
+	                 core_txd <= #1 1'b1;
+	             end
+	           else
+	             core_txd <= #1 ack_in;
+
+	        ST_STOP:
+	          if (core_ack)
+	            begin
+	                c_state  <= #1 ST_IDLE;
+	                core_cmd <= #1 `I2C_CMD_NOP;
+
+	                // generate command acknowledge signal
+	                cmd_ack  <= #1 1'b1;
+	            end
+
+	      endcase
+	  end
+endmodule
diff --git a/fpga/usrp3/lib/wishbone/i2c_master_defines.v b/fpga/usrp3/lib/wishbone/i2c_master_defines.v
new file mode 100644
index 000000000..ee3b694fa
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/i2c_master_defines.v
@@ -0,0 +1,64 @@
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+////  WISHBONE rev.B2 compliant I2C Master controller defines    ////
+////                                                             ////
+////                                                             ////
+////  Author: Richard Herveille                                  ////
+////          richard@asics.ws                                   ////
+////          www.asics.ws                                       ////
+////                                                             ////
+////  Downloaded from: http://www.opencores.org/projects/i2c/    ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+//// Copyright (C) 2001 Richard Herveille                        ////
+////                    richard@asics.ws                         ////
+////                                                             ////
+//// This source file may be used and distributed without        ////
+//// restriction provided that this copyright statement is not   ////
+//// removed from the file and that any derivative work contains ////
+//// the original copyright notice and the associated disclaimer.////
+////                                                             ////
+////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////
+//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////
+//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////
+//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////
+//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////
+//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////
+//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////
+//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////
+//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////
+//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////
+//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////
+//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////
+//// POSSIBILITY OF SUCH DAMAGE.                                 ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+
+//  CVS Log
+//
+//  $Id: i2c_master_defines.v,v 1.3 2001/11/05 11:59:25 rherveille Exp $
+//
+//  $Date: 2001/11/05 11:59:25 $
+//  $Revision: 1.3 $
+//  $Author: rherveille $
+//  $Locker:  $
+//  $State: Exp $
+//
+// Change History:
+//               $Log: i2c_master_defines.v,v $
+//               Revision 1.3  2001/11/05 11:59:25  rherveille
+//               Fixed wb_ack_o generation bug.
+//               Fixed bug in the byte_controller statemachine.
+//               Added headers.
+//
+
+
+// I2C registers wishbone addresses
+
+// bitcontroller states
+`define I2C_CMD_NOP   4'b0000
+`define I2C_CMD_START 4'b0001
+`define I2C_CMD_STOP  4'b0010
+`define I2C_CMD_WRITE 4'b0100
+`define I2C_CMD_READ  4'b1000
diff --git a/fpga/usrp3/lib/wishbone/i2c_master_top.v b/fpga/usrp3/lib/wishbone/i2c_master_top.v
new file mode 100644
index 000000000..be1fcfe55
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/i2c_master_top.v
@@ -0,0 +1,301 @@
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+////  WISHBONE revB.2 compliant I2C Master controller Top-level  ////
+////                                                             ////
+////                                                             ////
+////  Author: Richard Herveille                                  ////
+////          richard@asics.ws                                   ////
+////          www.asics.ws                                       ////
+////                                                             ////
+////  Downloaded from: http://www.opencores.org/projects/i2c/    ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+//// Copyright (C) 2001 Richard Herveille                        ////
+////                    richard@asics.ws                         ////
+////                                                             ////
+//// This source file may be used and distributed without        ////
+//// restriction provided that this copyright statement is not   ////
+//// removed from the file and that any derivative work contains ////
+//// the original copyright notice and the associated disclaimer.////
+////                                                             ////
+////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////
+//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////
+//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////
+//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////
+//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////
+//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////
+//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////
+//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////
+//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////
+//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////
+//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////
+//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////
+//// POSSIBILITY OF SUCH DAMAGE.                                 ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+
+//  CVS Log
+//
+//  $Id: i2c_master_top.v,v 1.11 2005/02/27 09:26:24 rherveille Exp $
+//
+//  $Date: 2005/02/27 09:26:24 $
+//  $Revision: 1.11 $
+//  $Author: rherveille $
+//  $Locker:  $
+//  $State: Exp $
+//
+// Change History:
+//               $Log: i2c_master_top.v,v $
+//               Revision 1.11  2005/02/27 09:26:24  rherveille
+//               Fixed register overwrite issue.
+//               Removed full_case pragma, replaced it by a default statement.
+//
+//               Revision 1.10  2003/09/01 10:34:38  rherveille
+//               Fix a blocking vs. non-blocking error in the wb_dat output mux.
+//
+//               Revision 1.9  2003/01/09 16:44:45  rherveille
+//               Fixed a bug in the Command Register declaration.
+//
+//               Revision 1.8  2002/12/26 16:05:12  rherveille
+//               Small code simplifications
+//
+//               Revision 1.7  2002/12/26 15:02:32  rherveille
+//               Core is now a Multimaster I2C controller
+//
+//               Revision 1.6  2002/11/30 22:24:40  rherveille
+//               Cleaned up code
+//
+//               Revision 1.5  2001/11/10 10:52:55  rherveille
+//               Changed PRER reset value from 0x0000 to 0xffff, conform specs.
+//
+
+// synopsys translate_off
+//`include "timescale.v"
+// synopsys translate_on
+
+`include "i2c_master_defines.v"
+
+module i2c_master_top(
+	wb_clk_i, wb_rst_i, arst_i, wb_adr_i, wb_dat_i, wb_dat_o,
+	wb_we_i, wb_stb_i, wb_cyc_i, wb_ack_o, wb_inta_o,
+	scl_pad_i, scl_pad_o, scl_padoen_o, sda_pad_i, sda_pad_o, sda_padoen_o );
+
+	// parameters
+	parameter ARST_LVL = 1'b0; // asynchronous reset level
+
+	//
+	// inputs & outputs
+	//
+
+	// wishbone signals
+	input        wb_clk_i;     // master clock input
+	input        wb_rst_i;     // synchronous active high reset
+	input        arst_i;       // asynchronous reset
+	input  [2:0] wb_adr_i;     // lower address bits
+	input  [7:0] wb_dat_i;     // databus input
+	output [7:0] wb_dat_o;     // databus output
+	input        wb_we_i;      // write enable input
+	input        wb_stb_i;     // stobe/core select signal
+	input        wb_cyc_i;     // valid bus cycle input
+	output       wb_ack_o;     // bus cycle acknowledge output
+	output       wb_inta_o;    // interrupt request signal output
+
+	reg [7:0] wb_dat_o;
+	reg wb_ack_o;
+	reg wb_inta_o;
+
+	// I2C signals
+	// i2c clock line
+	input  scl_pad_i;       // SCL-line input
+	output scl_pad_o;       // SCL-line output (always 1'b0)
+	output scl_padoen_o;    // SCL-line output enable (active low)
+
+	// i2c data line
+	input  sda_pad_i;       // SDA-line input
+	output sda_pad_o;       // SDA-line output (always 1'b0)
+	output sda_padoen_o;    // SDA-line output enable (active low)
+
+
+	//
+	// variable declarations
+	//
+
+	// registers
+	reg  [15:0] prer; // clock prescale register
+	reg  [ 7:0] ctr;  // control register
+	reg  [ 7:0] txr;  // transmit register
+	wire [ 7:0] rxr;  // receive register
+	reg  [ 7:0] cr;   // command register
+	wire [ 7:0] sr;   // status register
+
+	// done signal: command completed, clear command register
+	wire done;
+
+	// core enable signal
+	wire core_en;
+	wire ien;
+
+	// status register signals
+	wire irxack;
+	reg  rxack;       // received aknowledge from slave
+	reg  tip;         // transfer in progress
+	reg  irq_flag;    // interrupt pending flag
+	wire i2c_busy;    // bus busy (start signal detected)
+	wire i2c_al;      // i2c bus arbitration lost
+	reg  al;          // status register arbitration lost bit
+
+	//
+	// module body
+	//
+
+	// generate internal reset
+	wire rst_i = arst_i ^ ARST_LVL;
+
+	// generate wishbone signals
+	wire wb_wacc = wb_cyc_i & wb_stb_i & wb_we_i;
+
+	// generate acknowledge output signal
+	always @(posedge wb_clk_i)
+	  wb_ack_o <= #1 wb_cyc_i & wb_stb_i & ~wb_ack_o; // because timing is always honored
+
+	// assign DAT_O
+	always @(posedge wb_clk_i)
+	begin
+	  case (wb_adr_i) // synopsis parallel_case
+	    3'b000: wb_dat_o <= #1 prer[ 7:0];
+	    3'b001: wb_dat_o <= #1 prer[15:8];
+	    3'b010: wb_dat_o <= #1 ctr;
+	    3'b011: wb_dat_o <= #1 rxr; // write is transmit register (txr)
+	    3'b100: wb_dat_o <= #1 sr;  // write is command register (cr)
+	    3'b101: wb_dat_o <= #1 txr;
+	    3'b110: wb_dat_o <= #1 cr;
+	    3'b111: wb_dat_o <= #1 0;   // reserved
+	  endcase
+	end
+
+	// generate registers
+	always @(posedge wb_clk_i or negedge rst_i)
+	  if (!rst_i)
+	    begin
+	        prer <= #1 16'hffff;
+	        ctr  <= #1  8'h0;
+	        txr  <= #1  8'h0;
+	    end
+	  else if (wb_rst_i)
+	    begin
+	        prer <= #1 16'hffff;
+	        ctr  <= #1  8'h0;
+	        txr  <= #1  8'h0;
+	    end
+	  else
+	    if (wb_wacc)
+	      case (wb_adr_i) // synopsis parallel_case
+	         3'b000 : prer [ 7:0] <= #1 wb_dat_i;
+	         3'b001 : prer [15:8] <= #1 wb_dat_i;
+	         3'b010 : ctr         <= #1 wb_dat_i;
+	         3'b011 : txr         <= #1 wb_dat_i;
+	         default: ;
+	      endcase
+
+	// generate command register (special case)
+	always @(posedge wb_clk_i or negedge rst_i)
+	  if (~rst_i)
+	    cr <= #1 8'h0;
+	  else if (wb_rst_i)
+	    cr <= #1 8'h0;
+	  else if (wb_wacc)
+	    begin
+	        if (core_en & (wb_adr_i == 3'b100) )
+	          cr <= #1 wb_dat_i;
+	    end
+	  else
+	    begin
+	        if (done | i2c_al)
+	          cr[7:4] <= #1 4'h0;           // clear command bits when done
+	                                        // or when aribitration lost
+	        cr[2:1] <= #1 2'b0;             // reserved bits
+	        cr[0]   <= #1 2'b0;             // clear IRQ_ACK bit
+	    end
+
+
+	// decode command register
+	wire sta  = cr[7];
+	wire sto  = cr[6];
+	wire rd   = cr[5];
+	wire wr   = cr[4];
+	wire ack  = cr[3];
+	wire iack = cr[0];
+
+	// decode control register
+	assign core_en = ctr[7];
+	assign ien = ctr[6];
+
+	// hookup byte controller block
+	i2c_master_byte_ctrl byte_controller (
+		.clk      ( wb_clk_i     ),
+		.rst      ( wb_rst_i     ),
+		.nReset   ( rst_i        ),
+		.ena      ( core_en      ),
+		.clk_cnt  ( prer         ),
+		.start    ( sta          ),
+		.stop     ( sto          ),
+		.read     ( rd           ),
+		.write    ( wr           ),
+		.ack_in   ( ack          ),
+		.din      ( txr          ),
+		.cmd_ack  ( done         ),
+		.ack_out  ( irxack       ),
+		.dout     ( rxr          ),
+		.i2c_busy ( i2c_busy     ),
+		.i2c_al   ( i2c_al       ),
+		.scl_i    ( scl_pad_i    ),
+		.scl_o    ( scl_pad_o    ),
+		.scl_oen  ( scl_padoen_o ),
+		.sda_i    ( sda_pad_i    ),
+		.sda_o    ( sda_pad_o    ),
+		.sda_oen  ( sda_padoen_o )
+	);
+
+	// status register block + interrupt request signal
+	always @(posedge wb_clk_i or negedge rst_i)
+	  if (!rst_i)
+	    begin
+	        al       <= #1 1'b0;
+	        rxack    <= #1 1'b0;
+	        tip      <= #1 1'b0;
+	        irq_flag <= #1 1'b0;
+	    end
+	  else if (wb_rst_i)
+	    begin
+	        al       <= #1 1'b0;
+	        rxack    <= #1 1'b0;
+	        tip      <= #1 1'b0;
+	        irq_flag <= #1 1'b0;
+	    end
+	  else
+	    begin
+	        al       <= #1 i2c_al | (al & ~sta);
+	        rxack    <= #1 irxack;
+	        tip      <= #1 (rd | wr);
+	        irq_flag <= #1 (done | i2c_al | irq_flag) & ~iack; // interrupt request flag is always generated
+	    end
+
+	// generate interrupt request signals
+	always @(posedge wb_clk_i or negedge rst_i)
+	  if (!rst_i)
+	    wb_inta_o <= #1 1'b0;
+	  else if (wb_rst_i)
+	    wb_inta_o <= #1 1'b0;
+	  else
+	    wb_inta_o <= #1 irq_flag && ien; // interrupt signal is only generated when IEN (interrupt enable bit is set)
+
+	// assign status register bits
+	assign sr[7]   = rxack;
+	assign sr[6]   = i2c_busy;
+	assign sr[5]   = al;
+	assign sr[4:2] = 3'h0; // reserved
+	assign sr[1]   = tip;
+	assign sr[0]   = irq_flag;
+
+endmodule
diff --git a/fpga/usrp3/lib/wishbone/settings_bus.v b/fpga/usrp3/lib/wishbone/settings_bus.v
new file mode 100644
index 000000000..39f148916
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/settings_bus.v
@@ -0,0 +1,46 @@
+//
+// Copyright 2011-2012 Ettus Research LLC
+//
+
+
+
+// Grab settings off the wishbone bus, send them out to our simpler bus on the fast clock
+
+module settings_bus
+  #(parameter AWIDTH=16, parameter DWIDTH=32, parameter SWIDTH=8)
+    (input wb_clk, 
+     input wb_rst, 
+     input [AWIDTH-1:0] wb_adr_i,
+     input [DWIDTH-1:0] wb_dat_i,
+     input wb_stb_i,
+     input wb_we_i,
+     output reg wb_ack_o,
+     output reg strobe,
+     output reg [SWIDTH-1:0] addr,
+     output reg [31:0] data);
+
+   reg 	    stb_int, stb_int_d1;
+   
+   always @(posedge wb_clk)
+     if(wb_rst)
+       begin
+	  strobe <= 1'b0;
+	  addr <= {SWIDTH{1'b0}};
+	  data <= 32'd0;
+       end
+     else if(wb_we_i & wb_stb_i & ~wb_ack_o)
+       begin
+	  strobe <= 1'b1;
+	  addr <= wb_adr_i[SWIDTH+1:2];
+	  data <= wb_dat_i;
+       end
+     else
+       strobe <= 1'b0;
+
+   always @(posedge wb_clk)
+     if(wb_rst)
+       wb_ack_o <= 0;
+     else
+       wb_ack_o <= wb_stb_i & ~wb_ack_o;
+
+endmodule // settings_bus
diff --git a/fpga/usrp3/lib/wishbone/settings_readback.v b/fpga/usrp3/lib/wishbone/settings_readback.v
new file mode 100644
index 000000000..745571717
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/settings_readback.v
@@ -0,0 +1,40 @@
+//
+// Copyright 2011-2012 Ettus Research LLC
+//
+
+
+//
+// Use this module in conjunction with settings_bus.v to add stateful reads
+// to the settings bis. This enables you to do things like have registers reset atomicly
+// as they are read. It also pipelines the address path to ease timing.
+//
+
+module settings_readback
+  #(parameter AWIDTH=16, parameter DWIDTH=32, parameter RB_ADDRW=2)
+   (
+    input wb_clk, 
+    input wb_rst, 
+    input [AWIDTH-1:0] wb_adr_i,
+    input wb_stb_i,
+    input wb_we_i,
+    input [DWIDTH-1:0] rb_data,
+    output reg [RB_ADDRW-1:0] rb_addr,
+    output [DWIDTH-1:0] wb_dat_o,
+    output reg rb_rd_stb
+    );
+
+   always @(posedge wb_clk)
+     if (wb_stb_i && ~wb_we_i) begin
+	rb_addr <= wb_adr_i[RB_ADDRW+1:2];
+	rb_rd_stb <= 1'b1;	
+     end else begin
+	rb_rd_stb <= 1'b0;	
+     end
+   
+   assign wb_dat_o = rb_data;
+
+   
+
+endmodule // settings_readback
+
+  
\ No newline at end of file
diff --git a/fpga/usrp3/lib/wishbone/simple_uart.v b/fpga/usrp3/lib/wishbone/simple_uart.v
new file mode 100644
index 000000000..51dc23f16
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/simple_uart.v
@@ -0,0 +1,65 @@
+//
+// Copyright 2011 Ettus Research LLC
+//
+
+
+
+module simple_uart
+  #(parameter CLKDIV_DEFAULT = 16'd0)
+   (input clk_i, input rst_i,
+    input we_i, input stb_i, input cyc_i, output reg ack_o,
+    input [2:0] adr_i, input [31:0] dat_i, output reg [31:0] dat_o,
+    output rx_int_o, output tx_int_o, output tx_o, input rx_i, output baud_o);
+   
+   // Register Map
+   localparam SUART_CLKDIV = 0;
+   localparam SUART_TXLEVEL = 1;
+   localparam SUART_RXLEVEL = 2;
+   localparam SUART_TXCHAR = 3;
+   localparam SUART_RXCHAR = 4;
+   
+   wire       wb_acc = cyc_i & stb_i;            // WISHBONE access
+   wire       wb_wr  = wb_acc & we_i;            // WISHBONE write access
+   
+   reg [15:0] clkdiv;
+   wire [7:0] rx_char;
+   wire       tx_fifo_full, rx_fifo_empty;
+   wire [5:0] tx_fifo_level, rx_fifo_level;
+   
+   always @(posedge clk_i)
+     if (rst_i)
+       ack_o <= 1'b0;
+     else
+       ack_o <= wb_acc & ~ack_o;
+   
+   always @(posedge clk_i)
+     if (rst_i)
+       clkdiv <= CLKDIV_DEFAULT;
+     else if (wb_wr)
+       case(adr_i)
+	 SUART_CLKDIV : clkdiv <= dat_i[15:0];
+       endcase // case(adr_i)
+   
+   always @(posedge clk_i)
+     case (adr_i)
+       SUART_TXLEVEL : dat_o <= tx_fifo_level;
+       SUART_RXLEVEL : dat_o <= rx_fifo_level;
+       SUART_RXCHAR : dat_o <= rx_char;
+     endcase // case(adr_i)
+   
+   simple_uart_tx simple_uart_tx
+     (.clk(clk_i),.rst(rst_i),
+      .fifo_in(dat_i[7:0]),.fifo_write(ack_o && wb_wr && (adr_i == SUART_TXCHAR)),
+      .fifo_level(tx_fifo_level),.fifo_full(tx_fifo_full),
+      .clkdiv(clkdiv),.baudclk(baud_o),.tx(tx_o));
+   
+   simple_uart_rx simple_uart_rx
+     (.clk(clk_i),.rst(rst_i),
+      .fifo_out(rx_char),.fifo_read(ack_o && ~wb_wr && (adr_i == SUART_RXCHAR)),
+      .fifo_level(rx_fifo_level),.fifo_empty(rx_fifo_empty),
+      .clkdiv(clkdiv),.rx(rx_i));
+   
+   assign     tx_int_o = ~tx_fifo_full;
+   assign     rx_int_o = ~rx_fifo_empty;
+   
+endmodule // simple_uart
diff --git a/fpga/usrp3/lib/wishbone/simple_uart_rx.v b/fpga/usrp3/lib/wishbone/simple_uart_rx.v
new file mode 100644
index 000000000..7790a0a87
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/simple_uart_rx.v
@@ -0,0 +1,71 @@
+//
+// Copyright 2011-2013 Ettus Research LLC
+//
+
+
+
+
+module simple_uart_rx
+    #(parameter SIZE=0)
+    (input clk, input rst, 
+     output [7:0] fifo_out, input fifo_read, output [5:0] fifo_level, output fifo_empty, 
+     input [15:0] clkdiv, input rx);
+
+   reg 		  rx_d1, rx_d2;
+   always @(posedge clk)
+     if(rst)
+       {rx_d2,rx_d1} <= 0;
+     else
+       {rx_d2,rx_d1} <= {rx_d1,rx};
+   
+   reg [15:0] 	  baud_ctr;
+   reg [3:0] 	  bit_ctr;
+   reg [7:0] 	  sr;
+
+   wire 	  neg_trans = rx_d2 & ~rx_d1;
+   wire 	  shift_now = baud_ctr == (clkdiv>>1);
+   wire 	  stop_now = (bit_ctr == 10) && shift_now;
+   wire 	  go_now = (bit_ctr == 0) && neg_trans;
+   
+   always @(posedge clk)
+     if(rst)
+       sr <= 0;
+     else if(shift_now)
+       sr <= {rx_d2,sr[7:1]};
+   
+   always @(posedge clk)
+     if(rst)
+       baud_ctr <= 0;
+     else
+       if(go_now)
+	 baud_ctr <= 1;
+       else if(stop_now)
+	 baud_ctr <= 0;
+       else if(baud_ctr >= clkdiv)
+	 baud_ctr <= 1;
+       else if(baud_ctr != 0)
+	 baud_ctr <= baud_ctr + 1;
+
+   always @(posedge clk)
+     if(rst)
+       bit_ctr <= 0;
+     else 
+       if(go_now)
+	 bit_ctr <= 1;
+       else if(stop_now)
+	 bit_ctr <= 0;
+       else if(baud_ctr == clkdiv)
+	 bit_ctr <= bit_ctr + 1;
+
+   wire 	  i_tready, o_tvalid;
+   wire 	  full = ~i_tready;
+   wire 	  write = ~full & rx_d2 & stop_now;
+   assign fifo_empty = ~o_tvalid;
+   
+   axi_fifo #(.WIDTH(8), .SIZE(SIZE)) fifo
+     (.clk(clk),.reset(rst), .clear(1'b0),
+      .i_tdata(sr),.i_tvalid(write),.i_tready(i_tready),
+      .o_tdata(fifo_out),.o_tvalid(o_tvalid),.o_tready(fifo_read),
+      .space(),.occupied(fifo_level) );
+   
+endmodule // simple_uart_rx
diff --git a/fpga/usrp3/lib/wishbone/simple_uart_tb.v b/fpga/usrp3/lib/wishbone/simple_uart_tb.v
new file mode 100644
index 000000000..8b1427f99
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/simple_uart_tb.v
@@ -0,0 +1,127 @@
+module simple_uart_tb();
+   
+   localparam SUART_CLKDIV = 0;
+   localparam SUART_TXLEVEL = 1;
+   localparam SUART_RXLEVEL = 2;
+   localparam SUART_TXCHAR = 3;
+   localparam SUART_RXCHAR = 4;
+   
+   reg           clk;
+   reg 		 rst;
+
+   reg 		 we_i;
+   reg 		 stb_i;
+   reg 		 cyc_i;
+   wire 	 ack_o;
+   reg [2:0] 	 adr_i;
+   reg [31:0] 	 dat_i;
+   wire [31:0] 	 dat_o;
+   wire 	 rx_int_o;
+   wire 	 tx_int_o;
+   wire 	 tx_o;
+   reg 		 rx_i;
+   wire 	 baud_o;
+
+   reg [31:0] 	 read_data;
+   
+
+   initial 
+     clk = 0;
+
+   // 200MHz clock
+   always
+     #2.5 clk = ~clk;
+
+   initial begin
+      rst <= 0;
+      we_i <= 0;
+      stb_i <= 0;
+      cyc_i <= 0;
+      adr_i <= 0;
+      dat_i <= 0;
+      rx_i <= 0;
+   end
+   
+   
+   task write_wb;
+      input [31:0] data_in;
+      input [2:0]  addr_in;
+
+      begin
+	 @(negedge clk);	 
+	 dat_i <= data_in;
+	 adr_i <= addr_in;
+	 we_i <= 1;
+	 stb_i <= 1;
+	 cyc_i <= 1;
+	 @(negedge clk);
+	 while (ack_o == 0) begin
+	    @(negedge clk);
+	 end
+	 dat_i <= 0;
+	 adr_i <= 0;
+	 we_i <= 0;
+	 stb_i <= 0;
+	 cyc_i <= 0;
+      end
+   endtask // write_wb
+
+   
+   task read_wb;
+      output [31:0] data_out;
+      input [2:0]  addr_in;
+
+      begin
+	 @(negedge clk);	 
+	 adr_i <= addr_in;
+	 we_i <= 0;
+	 stb_i <= 1;
+	 cyc_i <= 1;
+	 @(negedge clk);
+	 while (ack_o == 0) begin
+	    @(negedge clk);
+	 end
+	 data_out <= dat_o;
+	 adr_i <= 0;
+	 stb_i <= 0;
+	 cyc_i <= 0;
+      end
+   endtask // write_wb
+
+   initial begin
+      @(negedge clk);    
+      rst <= 1;
+      repeat(10) @(negedge clk);
+      rst <= 0;
+      repeat(10) @(negedge clk);
+      write_wb(4'h0620,SUART_CLKDIV);
+      repeat(10) @(negedge clk);
+      read_wb(read_data,SUART_TXLEVEL);
+      repeat(10) @(negedge clk);
+   end // initial begin
+   
+   
+   
+   simple_uart
+     #(.CLKDIV_DEFAULT(16'd0))
+   simple_uart_i
+     (
+      .clk_i(clk),
+      .rst_i(rst),
+      .we_i(we_i),
+      .stb_i(stb_i),
+      .cyc_i(cyc_i),
+      .ack_o(ack_o),
+      .adr_i(adr_i),
+      .dat_i(dat_i),
+      .dat_o(dat_o),
+      .rx_int_o(rx_int_o),
+      .tx_int_o(tx_int_o), 
+      .tx_o(tx_o), 
+      .rx_i(rx_i),
+      .baud_o(baud_o)
+      );
+
+   
+
+endmodule // simple_uart_tb
diff --git a/fpga/usrp3/lib/wishbone/simple_uart_tx.v b/fpga/usrp3/lib/wishbone/simple_uart_tx.v
new file mode 100644
index 000000000..3eb1a1ecd
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/simple_uart_tx.v
@@ -0,0 +1,69 @@
+//
+// Copyright 2011-2013 Ettus Research LLC
+//
+
+
+
+module simple_uart_tx
+    #(parameter SIZE=0)
+    (input clk, input rst, 
+     input [7:0] fifo_in, input fifo_write, output [5:0] fifo_level, output fifo_full, 
+     input [15:0] clkdiv, output baudclk, output reg tx);
+   
+   reg [15:0] 	  baud_ctr;
+   reg [3:0] 	  bit_ctr;
+   
+   wire 	  read, empty;
+   wire [7:0] 	  char_to_send;
+   wire 	  i_tready, o_tvalid;
+   
+   assign fifo_full = ~i_tready;
+   assign empty = ~o_tvalid;
+   
+   axi_fifo #(.WIDTH(8), .SIZE(SIZE)) fifo
+     (.clk(clk),.reset(rst), .clear(1'b0),
+      .i_tdata(fifo_in), .i_tvalid(fifo_write), .i_tready(i_tready),
+      .o_tdata(char_to_send),.o_tvalid(o_tvalid),.o_tready(read),
+      .space(fifo_level),.occupied() );
+   
+   always @(posedge clk)
+     if(rst)
+       baud_ctr <= 0;
+     else if (baud_ctr >= clkdiv)
+       baud_ctr <= 0;
+     else
+       baud_ctr <= baud_ctr + 1;
+
+   always @(posedge clk)
+     if(rst)
+       bit_ctr <= 0;
+     else if(baud_ctr == clkdiv)
+       if(bit_ctr == 10)
+	 bit_ctr <= 0;
+       else if(bit_ctr != 0)
+	 bit_ctr <= bit_ctr + 1;
+       else if(~empty)
+	 bit_ctr <= 1;
+   
+   always @(posedge clk)
+     if(rst)
+       tx <= 1;
+     else
+       case(bit_ctr)
+	 0 : tx <= 1;
+	 1 : tx <= 0;
+	 2 : tx <= char_to_send[0];
+	 3 : tx <= char_to_send[1];
+	 4 : tx <= char_to_send[2];
+	 5 : tx <= char_to_send[3];
+	 6 : tx <= char_to_send[4];
+	 7 : tx <= char_to_send[5];
+	 8 : tx <= char_to_send[6];
+	 9 : tx <= char_to_send[7];
+	 default : tx <= 1;
+       endcase // case(bit_ctr)
+
+   assign 	  read = (bit_ctr == 9) && (baud_ctr == clkdiv);
+   assign 	  baudclk = (baud_ctr == 1);  // Only for debug purposes
+   
+endmodule // simple_uart_tx
diff --git a/fpga/usrp3/lib/wishbone/wb_1master.v b/fpga/usrp3/lib/wishbone/wb_1master.v
new file mode 100644
index 000000000..fb313efae
--- /dev/null
+++ b/fpga/usrp3/lib/wishbone/wb_1master.v
@@ -0,0 +1,464 @@
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+////  WISHBONE Connection Bus Top Level		                 ////
+////                                                             ////
+////                                                             ////
+////  Original Author: Johny Chi		                 ////
+////                   chisuhua@yahoo.com.cn                     ////
+////  Modified By Matt Ettus, matt@ettus.com                     ////
+////                                                             ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+////                                                              ////
+//// Copyright (C) 2000, 2007 Authors and OPENCORES.ORG           ////
+////                                                              ////
+//// This source file may be used and distributed without         ////
+//// restriction provided that this copyright statement is not    ////
+//// removed from the file and that any derivative work contains  ////
+//// the original copyright notice and the associated disclaimer. ////
+////                                                              ////
+//// This source file is free software; you can redistribute it   ////
+//// and/or modify it under the terms of the GNU Lesser General   ////
+//// Public License as published by the Free Software Foundation; ////
+//// either version 2.1 of the License, or (at your option) any   ////
+//// later version.                                               ////
+////                                                              ////
+//// This source is distributed in the hope that it will be       ////
+//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
+//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
+//// PURPOSE.  See the GNU Lesser General Public License for more ////
+//// details.                                                     ////
+////                                                              ////
+//// You should have received a copy of the GNU Lesser General    ////
+//// Public License along with this source; if not, download it   ////
+//// from http://www.opencores.org/lgpl.shtml                     ////
+////                                                              ////
+//////////////////////////////////////////////////////////////////////
+//
+//   Up to 8 slaves share a Wishbone Bus connection to 1 master
+
+  module wb_1master
+    #(parameter	decode_w = 8,			// address decode width
+      parameter	s0_addr = 8'h0,			// slave 0 address
+      parameter	s0_mask = 8'h0,			// slave 0 don't cares
+      parameter	s1_addr = 8'h0,			// slave 1 address
+      parameter	s1_mask = 8'h0,			// slave 1 don't cares
+      parameter	s2_addr = 8'h0,			// slave 2 address
+      parameter	s2_mask = 8'h0,			// slave 2 don't cares
+      parameter	s3_addr = 8'h0,			// slave 3 address
+      parameter	s3_mask = 8'h0,			// slave 3 don't cares
+      parameter	s4_addr = 8'h0,			// slave 4 address
+      parameter	s4_mask = 8'h0,			// slave 4 don't cares
+      parameter	s5_addr = 8'h0,			// slave 5 address
+      parameter	s5_mask = 8'h0,			// slave 5 don't cares
+      parameter	s6_addr = 8'h0,			// slave 6 address
+      parameter	s6_mask = 8'h0,			// slave 6 don't cares
+      parameter	s7_addr = 8'h0,			// slave 7 address
+      parameter	s7_mask = 8'h0,			// slave 7 don't cares
+      parameter	s8_addr = 8'h0,			// slave 8 address
+      parameter	s8_mask = 8'h0,			// slave 8 don't cares
+      parameter	s9_addr = 8'h0,			// slave 9 address
+      parameter	s9_mask = 8'h0,			// slave 9 don't cares
+      parameter	sa_addr = 8'h0,			// slave a address
+      parameter	sa_mask = 8'h0,			// slave a don't cares
+      parameter	sb_addr = 8'h0,			// slave b address
+      parameter	sb_mask = 8'h0,			// slave b don't cares
+      parameter	sc_addr = 8'h0,			// slave c address
+      parameter	sc_mask = 8'h0,			// slave c don't cares
+      parameter	sd_addr = 8'h0,			// slave d address
+      parameter	sd_mask = 8'h0,			// slave d don't cares
+      parameter	se_addr = 8'h0,			// slave e address
+      parameter	se_mask = 8'h0,			// slave e don't cares
+      parameter	sf_addr = 8'h0,			// slave f address
+      parameter	sf_mask = 8'h0,			// slave f don't cares
+            
+      parameter	dw = 32,		// Data bus Width
+      parameter	aw = 32,		// Address bus Width
+      parameter	sw = 4)                 // Number of Select Lines
+      
+      (input clk_i, 
+       input rst_i,
+       
+       // Master  Interface
+       input [dw-1:0]   m0_dat_i,
+       output [dw-1:0] 	m0_dat_o,
+       input [aw-1:0] 	m0_adr_i,
+       input [sw-1:0] 	m0_sel_i,
+       input 		m0_we_i,
+       input 		m0_cyc_i,
+       input 		m0_stb_i,
+       output 		m0_ack_o,
+       output 		m0_err_o,
+       output 		m0_rty_o,
+       
+       // Slave Interfaces
+       input [dw-1:0] 	s0_dat_i,
+       output [dw-1:0] 	s0_dat_o,
+       output [aw-1:0] 	s0_adr_o,
+       output [sw-1:0] 	s0_sel_o,
+       output 		s0_we_o,
+       output 		s0_cyc_o,
+       output 		s0_stb_o,
+       input 		s0_ack_i,
+       input 		s0_err_i,
+       input 		s0_rty_i,
+       
+       input [dw-1:0] 	s1_dat_i,
+       output [dw-1:0] 	s1_dat_o,
+       output [aw-1:0] 	s1_adr_o,
+       output [sw-1:0] 	s1_sel_o,
+       output 		s1_we_o,
+       output 		s1_cyc_o,
+       output 		s1_stb_o,
+       input 		s1_ack_i,
+       input 		s1_err_i,
+       input 		s1_rty_i,
+       
+       input [dw-1:0] 	s2_dat_i,
+       output [dw-1:0] 	s2_dat_o,
+       output [aw-1:0] 	s2_adr_o,
+       output [sw-1:0] 	s2_sel_o,
+       output 		s2_we_o,
+       output 		s2_cyc_o,
+       output 		s2_stb_o,
+       input 		s2_ack_i,
+       input 		s2_err_i,
+       input 		s2_rty_i,
+       
+       input [dw-1:0] 	s3_dat_i,
+       output [dw-1:0] 	s3_dat_o,
+       output [aw-1:0] 	s3_adr_o,
+       output [sw-1:0] 	s3_sel_o,
+       output 		s3_we_o,
+       output 		s3_cyc_o,
+       output 		s3_stb_o,
+       input 		s3_ack_i,
+       input 		s3_err_i,
+       input 		s3_rty_i,
+       
+       input [dw-1:0] 	s4_dat_i,
+       output [dw-1:0] 	s4_dat_o,
+       output [aw-1:0] 	s4_adr_o,
+       output [sw-1:0] 	s4_sel_o,
+       output 		s4_we_o,
+       output 		s4_cyc_o,
+       output 		s4_stb_o,
+       input 		s4_ack_i,
+       input 		s4_err_i,
+       input 		s4_rty_i,
+       
+       input [dw-1:0] 	s5_dat_i,
+       output [dw-1:0] 	s5_dat_o,
+       output [aw-1:0] 	s5_adr_o,
+       output [sw-1:0] 	s5_sel_o,
+       output 		s5_we_o,
+       output 		s5_cyc_o,
+       output 		s5_stb_o,
+       input 		s5_ack_i,
+       input 		s5_err_i,
+       input 		s5_rty_i,
+       
+       input [dw-1:0] 	s6_dat_i,
+       output [dw-1:0] 	s6_dat_o,
+       output [aw-1:0] 	s6_adr_o,
+       output [sw-1:0] 	s6_sel_o,
+       output 		s6_we_o,
+       output 		s6_cyc_o,
+       output 		s6_stb_o,
+       input 		s6_ack_i,
+       input 		s6_err_i,
+       input 		s6_rty_i,
+       
+       input [dw-1:0] 	s7_dat_i,
+       output [dw-1:0] 	s7_dat_o,
+       output [aw-1:0] 	s7_adr_o,
+       output [sw-1:0] 	s7_sel_o,
+       output 		s7_we_o,
+       output 		s7_cyc_o,
+       output 		s7_stb_o,
+       input 		s7_ack_i,
+       input 		s7_err_i,
+       input 		s7_rty_i,
+
+       input [dw-1:0] 	s8_dat_i,
+       output [dw-1:0] 	s8_dat_o,
+       output [aw-1:0] 	s8_adr_o,
+       output [sw-1:0] 	s8_sel_o,
+       output 		s8_we_o,
+       output 		s8_cyc_o,
+       output 		s8_stb_o,
+       input 		s8_ack_i,
+       input 		s8_err_i,
+       input 		s8_rty_i,
+       
+       input [dw-1:0] 	s9_dat_i,
+       output [dw-1:0] 	s9_dat_o,
+       output [aw-1:0] 	s9_adr_o,
+       output [sw-1:0] 	s9_sel_o,
+       output 		s9_we_o,
+       output 		s9_cyc_o,
+       output 		s9_stb_o,
+       input 		s9_ack_i,
+       input 		s9_err_i,
+       input 		s9_rty_i,
+       
+       input [dw-1:0] 	sa_dat_i,
+       output [dw-1:0] 	sa_dat_o,
+       output [aw-1:0] 	sa_adr_o,
+       output [sw-1:0] 	sa_sel_o,
+       output 		sa_we_o,
+       output 		sa_cyc_o,
+       output 		sa_stb_o,
+       input 		sa_ack_i,
+       input 		sa_err_i,
+       input 		sa_rty_i,
+       
+       input [dw-1:0] 	sb_dat_i,
+       output [dw-1:0] 	sb_dat_o,
+       output [aw-1:0] 	sb_adr_o,
+       output [sw-1:0] 	sb_sel_o,
+       output 		sb_we_o,
+       output 		sb_cyc_o,
+       output 		sb_stb_o,
+       input 		sb_ack_i,
+       input 		sb_err_i,
+       input 		sb_rty_i,
+       
+       input [dw-1:0] 	sc_dat_i,
+       output [dw-1:0] 	sc_dat_o,
+       output [aw-1:0] 	sc_adr_o,
+       output [sw-1:0] 	sc_sel_o,
+       output 		sc_we_o,
+       output 		sc_cyc_o,
+       output 		sc_stb_o,
+       input 		sc_ack_i,
+       input 		sc_err_i,
+       input 		sc_rty_i,
+       
+       input [dw-1:0] 	sd_dat_i,
+       output [dw-1:0] 	sd_dat_o,
+       output [aw-1:0] 	sd_adr_o,
+       output [sw-1:0] 	sd_sel_o,
+       output 		sd_we_o,
+       output 		sd_cyc_o,
+       output 		sd_stb_o,
+       input 		sd_ack_i,
+       input 		sd_err_i,
+       input 		sd_rty_i,
+       
+       input [dw-1:0] 	se_dat_i,
+       output [dw-1:0] 	se_dat_o,
+       output [aw-1:0] 	se_adr_o,
+       output [sw-1:0] 	se_sel_o,
+       output 		se_we_o,
+       output 		se_cyc_o,
+       output 		se_stb_o,
+       input 		se_ack_i,
+       input 		se_err_i,
+       input 		se_rty_i,
+       
+       input [dw-1:0] 	sf_dat_i,
+       output [dw-1:0] 	sf_dat_o,
+       output [aw-1:0] 	sf_adr_o,
+       output [sw-1:0] 	sf_sel_o,
+       output 		sf_we_o,
+       output 		sf_cyc_o,
+       output 		sf_stb_o,
+       input 		sf_ack_i,
+       input 		sf_err_i,
+       input 		sf_rty_i
+       );
+   
+   // ////////////////////////////////////////////////////////////////
+   //
+   // Local wires
+   //
+   
+   wire [15:0] 		ssel_dec;
+   reg [dw-1:0] 	i_dat_s;	// internal share bus , slave data to master
+   
+   // Master output Interface
+   assign 		m0_dat_o = i_dat_s;
+   
+   always @*
+     case(ssel_dec)
+       1   : i_dat_s <= s0_dat_i;
+       2   : i_dat_s <= s1_dat_i;
+       4   : i_dat_s <= s2_dat_i;
+       8   : i_dat_s <= s3_dat_i;
+       16  : i_dat_s <= s4_dat_i;
+       32  : i_dat_s <= s5_dat_i;
+       64  : i_dat_s <= s6_dat_i;
+       128 : i_dat_s <= s7_dat_i;
+       256 : i_dat_s <= s8_dat_i;
+       512 : i_dat_s <= s9_dat_i;
+       1024 : i_dat_s <= sa_dat_i;
+       2048 : i_dat_s <= sb_dat_i;
+       4096 : i_dat_s <= sc_dat_i;
+       8192 : i_dat_s <= sd_dat_i;
+       16384 : i_dat_s <= se_dat_i;
+       32768 : i_dat_s <= sf_dat_i;
+       default : i_dat_s <= s0_dat_i;
+     endcase // case(ssel_dec)
+   
+   assign 		{m0_ack_o, m0_err_o, m0_rty_o} 
+     =  {s0_ack_i | s1_ack_i | s2_ack_i | s3_ack_i | s4_ack_i | s5_ack_i | s6_ack_i | s7_ack_i |
+	 s8_ack_i | s9_ack_i | sa_ack_i | sb_ack_i | sc_ack_i | sd_ack_i | se_ack_i | sf_ack_i ,
+	 s0_err_i | s1_err_i | s2_err_i | s3_err_i | s4_err_i | s5_err_i | s6_err_i | s7_err_i |
+	 s8_err_i | s9_err_i | sa_err_i | sb_err_i | sc_err_i | sd_err_i | se_err_i | sf_err_i ,
+	 s0_rty_i | s1_rty_i | s2_rty_i | s3_rty_i | s4_rty_i | s5_rty_i | s6_rty_i | s7_rty_i |
+	 s8_rty_i | s9_rty_i | sa_rty_i | sb_rty_i | sc_rty_i | sd_rty_i | se_rty_i | sf_rty_i };
+
+   // Slave output interfaces
+   assign 		s0_adr_o = m0_adr_i;
+   assign 		s0_sel_o = m0_sel_i;
+   assign 		s0_dat_o = m0_dat_i;
+   assign 		s0_we_o = m0_we_i;
+   assign 		s0_cyc_o = m0_cyc_i;
+   assign 		s0_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[0];   
+   
+   assign 		s1_adr_o = m0_adr_i;
+   assign 		s1_sel_o = m0_sel_i;
+   assign 		s1_dat_o = m0_dat_i;
+   assign 		s1_we_o = m0_we_i;
+   assign 		s1_cyc_o = m0_cyc_i;
+   assign 		s1_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[1];   
+   
+   assign 		s2_adr_o = m0_adr_i;
+   assign 		s2_sel_o = m0_sel_i;
+   assign 		s2_dat_o = m0_dat_i;
+   assign 		s2_we_o = m0_we_i;
+   assign 		s2_cyc_o = m0_cyc_i;
+   assign 		s2_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[2];   
+   
+   assign 		s3_adr_o = m0_adr_i;
+   assign 		s3_sel_o = m0_sel_i;
+   assign 		s3_dat_o = m0_dat_i;
+   assign 		s3_we_o = m0_we_i;
+   assign 		s3_cyc_o = m0_cyc_i;
+   assign 		s3_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[3];   
+   
+   assign 		s4_adr_o = m0_adr_i;
+   assign 		s4_sel_o = m0_sel_i;
+   assign 		s4_dat_o = m0_dat_i;
+   assign 		s4_we_o = m0_we_i;
+   assign 		s4_cyc_o = m0_cyc_i;
+   assign 		s4_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[4];   
+   
+   assign 		s5_adr_o = m0_adr_i;
+   assign 		s5_sel_o = m0_sel_i;
+   assign 		s5_dat_o = m0_dat_i;
+   assign 		s5_we_o = m0_we_i;
+   assign 		s5_cyc_o = m0_cyc_i;
+   assign 		s5_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[5];   
+   
+   assign 		s6_adr_o = m0_adr_i;
+   assign 		s6_sel_o = m0_sel_i;
+   assign 		s6_dat_o = m0_dat_i;
+   assign 		s6_we_o = m0_we_i;
+   assign 		s6_cyc_o = m0_cyc_i;
+   assign 		s6_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[6];   
+   
+   assign 		s7_adr_o = m0_adr_i;
+   assign 		s7_sel_o = m0_sel_i;
+   assign 		s7_dat_o = m0_dat_i;
+   assign 		s7_we_o = m0_we_i;
+   assign 		s7_cyc_o = m0_cyc_i;
+   assign 		s7_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[7];   
+   
+   assign 		s8_adr_o = m0_adr_i;
+   assign 		s8_sel_o = m0_sel_i;
+   assign 		s8_dat_o = m0_dat_i;
+   assign 		s8_we_o = m0_we_i;
+   assign 		s8_cyc_o = m0_cyc_i;
+   assign 		s8_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[8];   
+   
+   assign 		s9_adr_o = m0_adr_i;
+   assign 		s9_sel_o = m0_sel_i;
+   assign 		s9_dat_o = m0_dat_i;
+   assign 		s9_we_o = m0_we_i;
+   assign 		s9_cyc_o = m0_cyc_i;
+   assign 		s9_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[9];   
+   
+   assign 		sa_adr_o = m0_adr_i;
+   assign 		sa_sel_o = m0_sel_i;
+   assign 		sa_dat_o = m0_dat_i;
+   assign 		sa_we_o = m0_we_i;
+   assign 		sa_cyc_o = m0_cyc_i;
+   assign 		sa_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[10];   
+   
+   assign 		sb_adr_o = m0_adr_i;
+   assign 		sb_sel_o = m0_sel_i;
+   assign 		sb_dat_o = m0_dat_i;
+   assign 		sb_we_o = m0_we_i;
+   assign 		sb_cyc_o = m0_cyc_i;
+   assign 		sb_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[11];   
+   
+   assign 		sc_adr_o = m0_adr_i;
+   assign 		sc_sel_o = m0_sel_i;
+   assign 		sc_dat_o = m0_dat_i;
+   assign 		sc_we_o = m0_we_i;
+   assign 		sc_cyc_o = m0_cyc_i;
+   assign 		sc_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[12];   
+   
+   assign 		sd_adr_o = m0_adr_i;
+   assign 		sd_sel_o = m0_sel_i;
+   assign 		sd_dat_o = m0_dat_i;
+   assign 		sd_we_o = m0_we_i;
+   assign 		sd_cyc_o = m0_cyc_i;
+   assign 		sd_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[13];   
+   
+   assign 		se_adr_o = m0_adr_i;
+   assign 		se_sel_o = m0_sel_i;
+   assign 		se_dat_o = m0_dat_i;
+   assign 		se_we_o = m0_we_i;
+   assign 		se_cyc_o = m0_cyc_i;
+   assign 		se_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[14];   
+   
+   assign 		sf_adr_o = m0_adr_i;
+   assign 		sf_sel_o = m0_sel_i;
+   assign 		sf_dat_o = m0_dat_i;
+   assign 		sf_we_o = m0_we_i;
+   assign 		sf_cyc_o = m0_cyc_i;
+   assign 		sf_stb_o = m0_cyc_i & m0_stb_i & ssel_dec[15];   
+   
+   // Address decode logic
+   // WARNING -- must make sure these are mutually exclusive!
+
+
+   assign 		ssel_dec[0] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s0_addr) & s0_mask);
+   assign 		ssel_dec[1] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s1_addr) & s1_mask);
+   assign 		ssel_dec[2] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s2_addr) & s2_mask);
+   assign 		ssel_dec[3] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s3_addr) & s3_mask);
+   assign 		ssel_dec[4] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s4_addr) & s4_mask);
+   assign 		ssel_dec[5] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s5_addr) & s5_mask);
+   assign 		ssel_dec[6] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s6_addr) & s6_mask);
+   assign 		ssel_dec[7] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s7_addr) & s7_mask);
+   assign 		ssel_dec[8] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s8_addr) & s8_mask);
+   assign 		ssel_dec[9] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ s9_addr) & s9_mask);
+   assign 		ssel_dec[10] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ sa_addr) & sa_mask);
+   assign 		ssel_dec[11] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ sb_addr) & sb_mask);
+   assign 		ssel_dec[12] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ sc_addr) & sc_mask);
+   assign 		ssel_dec[13] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ sd_addr) & sd_mask);
+   assign 		ssel_dec[14] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ se_addr) & se_mask);
+   assign 		ssel_dec[15] = ~|((m0_adr_i[aw-1:aw-decode_w] ^ sf_addr) & sf_mask);
+
+/*
+   assign 		ssel_dec[0] = (m0_adr_i[aw -1 : aw - decode_w ] == s0_addr);
+   assign 		ssel_dec[1] = (m0_adr_i[aw -1 : aw - decode_w ] == s1_addr);
+   assign 		ssel_dec[2] = (m0_adr_i[aw -1 : aw - decode_w ] == s2_addr);
+   assign 		ssel_dec[3] = (m0_adr_i[aw -1 : aw - decode_w ] == s3_addr);
+   assign 		ssel_dec[4] = (m0_adr_i[aw -1 : aw - decode_w ] == s4_addr);
+   assign 		ssel_dec[5] = (m0_adr_i[aw -1 : aw - decode_w ] == s5_addr);
+   assign 		ssel_dec[6] = (m0_adr_i[aw -1 : aw - decode_w ] == s6_addr);
+   assign 		ssel_dec[7] = (m0_adr_i[aw -1 : aw - decode_w ] == s7_addr);
+   assign 		ssel_dec[8] = (m0_adr_i[aw -1 : aw - decode_w ] == s8_addr);
+   assign 		ssel_dec[9] = (m0_adr_i[aw -1 : aw - decode_w ] == s9_addr);
+   assign 		ssel_dec[10] = (m0_adr_i[aw -1 : aw - decode_w ] == sa_addr);
+   assign 		ssel_dec[11] = (m0_adr_i[aw -1 : aw - decode_w ] == sb_addr);
+   assign 		ssel_dec[12] = (m0_adr_i[aw -1 : aw - decode_w ] == sc_addr);
+   assign 		ssel_dec[13] = (m0_adr_i[aw -1 : aw - decode_w ] == sd_addr);
+   assign 		ssel_dec[14] = (m0_adr_i[aw -1 : aw - decode_w ] == se_addr);
+   assign 		ssel_dec[15] = (m0_adr_i[aw -1 : aw - decode_w ] == sf_addr);
+ */ 
+endmodule // wb_1master