Merge branch 'fpga_next' into next

13 files changed, 658 insertions, 610 deletions

diff --git a/fpga/usrp2/sdr_lib/Makefile.srcs b/fpga/usrp2/sdr_lib/Makefile.srcs
index 629b92cc8..e6c4c5343 100644
--- a/fpga/usrp2/sdr_lib/Makefile.srcs
+++ b/fpga/usrp2/sdr_lib/Makefile.srcs
@@ -1,5 +1,5 @@
 #
-# Copyright 2010 Ettus Research LLC
+# Copyright 2010-2012 Ettus Research LLC
 #
 
 ##################################################
@@ -23,9 +23,10 @@ clip_reg.v \
 cordic.v \
 cordic_z24.v \
 cordic_stage.v \
-dsp_core_rx.v \
-dsp_core_tx.v \
+ddc_chain.v \
+duc_chain.v \
 dspengine_16to8.v \
+dspengine_8to16.v \
 hb_dec.v \
 hb_interp.v \
 pipectrl.v \
@@ -39,4 +40,6 @@ sign_extend.v \
 small_hb_dec.v \
 small_hb_int.v \
 tx_frontend.v \
+dsp_tx_glue.v \
+dsp_rx_glue.v \
 ))
diff --git a/fpga/usrp2/sdr_lib/cordic_z24.v b/fpga/usrp2/sdr_lib/cordic_z24.v
index 97b7beaf7..51b074a33 100644
--- a/fpga/usrp2/sdr_lib/cordic_z24.v
+++ b/fpga/usrp2/sdr_lib/cordic_z24.v
@@ -119,8 +119,6 @@ module cordic_z24(clock, reset, enable, xi, yi, zi, xo, yo, zo );
    assign xo = x20[bitwidth:1];  
    assign yo = y20[bitwidth:1];
    assign zo = z20;		  
-   //assign xo = x20[bitwidth+1:2];  // CORDIC gain is ~1.6, plus gain from rotating vectors
-   //assign yo = y20[bitwidth+1:2];
 
 endmodule // cordic
 
diff --git a/fpga/usrp2/sdr_lib/ddc_chain.v b/fpga/usrp2/sdr_lib/ddc_chain.v
new file mode 100644
index 000000000..c32c9f491
--- /dev/null
+++ b/fpga/usrp2/sdr_lib/ddc_chain.v
@@ -0,0 +1,190 @@
+//
+// Copyright 2011-2012 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+//! The USRP digital down-conversion chain
+
+module ddc_chain
+  #(
+    parameter BASE = 0,
+    parameter DSPNO = 0,
+    parameter WIDTH = 24
+  )
+  (input clk, input rst, input clr,
+   input set_stb, input [7:0] set_addr, input [31:0] set_data,
+   input set_stb_user, input [7:0] set_addr_user, input [31:0] set_data_user,
+
+   // From RX frontend
+   input [WIDTH-1:0] rx_fe_i,
+   input [WIDTH-1:0] rx_fe_q,
+
+   // To RX control
+   output [31:0] sample,
+   input run,
+   output strobe,
+   output [31:0] debug
+   );
+
+   localparam  cwidth = 25;
+   localparam  zwidth = 24;
+
+   wire ddc_enb;
+   wire [31:0] phase_inc;
+   reg [31:0]  phase;
+
+   wire [17:0] scale_factor;
+   wire [cwidth-1:0] i_cordic, q_cordic;
+   wire [WIDTH-1:0] i_cordic_clip, q_cordic_clip;
+   wire [WIDTH-1:0] i_cic, q_cic;
+   wire [WIDTH-1:0] i_hb1, q_hb1;
+   wire [WIDTH-1:0] i_hb2, q_hb2;
+   
+   wire        strobe_cic, strobe_hb1, strobe_hb2;
+   wire        enable_hb1, enable_hb2;
+   wire [7:0]  cic_decim_rate;
+
+   reg [WIDTH-1:0]  rx_fe_i_mux, rx_fe_q_mux;
+   wire        realmode;
+   wire        swap_iq;
+   
+   setting_reg #(.my_addr(BASE+0)) sr_0
+     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+      .in(set_data),.out(phase_inc),.changed());
+
+   setting_reg #(.my_addr(BASE+1), .width(18)) sr_1
+     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+      .in(set_data),.out(scale_factor),.changed());
+
+   setting_reg #(.my_addr(BASE+2), .width(10)) sr_2
+     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+      .in(set_data),.out({enable_hb1, enable_hb2, cic_decim_rate}),.changed());
+
+   setting_reg #(.my_addr(BASE+3), .width(2)) sr_3
+     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+      .in(set_data),.out({realmode,swap_iq}),.changed());
+
+   // MUX so we can do realmode signals on either input
+   
+   always @(posedge clk)
+     if(swap_iq)
+       begin
+	  rx_fe_i_mux <= rx_fe_q;
+	  rx_fe_q_mux <= realmode ? 0 : rx_fe_i;
+       end
+     else
+       begin
+	  rx_fe_i_mux <= rx_fe_i;
+	  rx_fe_q_mux <= realmode ? 0 : rx_fe_q;
+       end
+
+   // NCO
+   always @(posedge clk)
+     if(rst)
+       phase <= 0;
+     else if(~ddc_enb)
+       phase <= 0;
+     else
+       phase <= phase + phase_inc;
+
+   //sign extension of cordic input
+   wire [WIDTH-1:0] to_ddc_chain_i, to_ddc_chain_q;
+   wire [cwidth-1:0] to_cordic_i, to_cordic_q;
+   sign_extend #(.bits_in(WIDTH), .bits_out(cwidth)) sign_extend_cordic_i (.in(to_ddc_chain_i), .out(to_cordic_i));
+   sign_extend #(.bits_in(WIDTH), .bits_out(cwidth)) sign_extend_cordic_q (.in(to_ddc_chain_q), .out(to_cordic_q));
+
+   // CORDIC  24-bit I/O
+   cordic_z24 #(.bitwidth(cwidth))
+     cordic(.clock(clk), .reset(rst), .enable(ddc_enb),
+	    .xi(to_cordic_i),. yi(to_cordic_q), .zi(phase[31:32-zwidth]),
+	    .xo(i_cordic),.yo(q_cordic),.zo() );
+
+   clip_reg #(.bits_in(cwidth), .bits_out(WIDTH)) clip_i
+     (.clk(clk), .in(i_cordic), .strobe_in(1'b1), .out(i_cordic_clip));
+   clip_reg #(.bits_in(cwidth), .bits_out(WIDTH)) clip_q
+     (.clk(clk), .in(q_cordic), .strobe_in(1'b1), .out(q_cordic_clip));
+
+   // CIC decimator  24 bit I/O
+   cic_strober cic_strober(.clock(clk),.reset(rst),.enable(ddc_enb),.rate(cic_decim_rate),
+			   .strobe_fast(1),.strobe_slow(strobe_cic) );
+
+   cic_decim #(.bw(WIDTH))
+     decim_i (.clock(clk),.reset(rst),.enable(ddc_enb),
+	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
+	      .signal_in(i_cordic_clip),.signal_out(i_cic));
+   
+   cic_decim #(.bw(WIDTH))
+     decim_q (.clock(clk),.reset(rst),.enable(ddc_enb),
+	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
+	      .signal_in(q_cordic_clip),.signal_out(q_cic));
+
+   // First (small) halfband  24 bit I/O
+   small_hb_dec #(.WIDTH(WIDTH)) small_hb_i
+     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(ddc_enb),
+      .stb_in(strobe_cic),.data_in(i_cic),.stb_out(strobe_hb1),.data_out(i_hb1));
+   
+   small_hb_dec #(.WIDTH(WIDTH)) small_hb_q
+     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(ddc_enb),
+      .stb_in(strobe_cic),.data_in(q_cic),.stb_out(),.data_out(q_hb1));
+
+   // Second (large) halfband  24 bit I/O
+   wire [8:0]  cpi_hb = enable_hb1 ? {cic_decim_rate,1'b0} : {1'b0,cic_decim_rate};
+   hb_dec #(.WIDTH(WIDTH)) hb_i
+     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(ddc_enb),.cpi(cpi_hb),
+      .stb_in(strobe_hb1),.data_in(i_hb1),.stb_out(strobe_hb2),.data_out(i_hb2));
+
+   hb_dec #(.WIDTH(WIDTH)) hb_q
+     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(ddc_enb),.cpi(cpi_hb),
+      .stb_in(strobe_hb1),.data_in(q_hb1),.stb_out(),.data_out(q_hb2));
+
+   //scalar operation (gain of 6 bits)
+   wire [35:0] prod_i, prod_q;
+
+   MULT18X18S mult_i
+     (.P(prod_i), .A(i_hb2[WIDTH-1:WIDTH-18]), .B(scale_factor), .C(clk), .CE(strobe_hb2), .R(rst) );
+   MULT18X18S mult_q
+     (.P(prod_q), .A(q_hb2[WIDTH-1:WIDTH-18]), .B(scale_factor), .C(clk), .CE(strobe_hb2), .R(rst) );
+
+   //pipeline for the multiplier (gain of 10 bits)
+   reg [WIDTH-1:0] prod_reg_i, prod_reg_q;
+   reg strobe_mult;
+
+   always @(posedge clk) begin
+       strobe_mult <= strobe_hb2;
+       prod_reg_i <= prod_i[33:34-WIDTH];
+       prod_reg_q <= prod_q[33:34-WIDTH];
+   end
+
+   // Round final answer to 16 bits
+   wire [31:0] ddc_chain_out;
+   wire ddc_chain_stb;
+
+   round_sd #(.WIDTH_IN(WIDTH),.WIDTH_OUT(16)) round_i
+     (.clk(clk),.reset(rst), .in(prod_reg_i),.strobe_in(strobe_mult), .out(ddc_chain_out[31:16]), .strobe_out(ddc_chain_stb));
+
+   round_sd #(.WIDTH_IN(WIDTH),.WIDTH_OUT(16)) round_q
+     (.clk(clk),.reset(rst), .in(prod_reg_q),.strobe_in(strobe_mult), .out(ddc_chain_out[15:0]), .strobe_out());
+
+   dsp_rx_glue #(.DSPNO(DSPNO), .WIDTH(WIDTH)) custom(
+    .clock(clk), .reset(rst), .clear(clr), .enable(run),
+    .set_stb(set_stb_user), .set_addr(set_addr_user), .set_data(set_data_user),
+    .frontend_i(rx_fe_i_mux), .frontend_q(rx_fe_q_mux),
+    .ddc_in_i(to_ddc_chain_i), .ddc_in_q(to_ddc_chain_q),
+    .ddc_out_sample(ddc_chain_out), .ddc_out_strobe(ddc_chain_stb), .ddc_out_enable(ddc_enb),
+    .bb_sample(sample), .bb_strobe(strobe));
+
+   assign      debug = {enable_hb1, enable_hb2, run, strobe, strobe_cic, strobe_hb1, strobe_hb2};
+   
+endmodule // ddc_chain
diff --git a/fpga/usrp2/sdr_lib/dsp_core_rx.v b/fpga/usrp2/sdr_lib/dsp_core_rx.v
deleted file mode 100644
index d1c7e238a..000000000
--- a/fpga/usrp2/sdr_lib/dsp_core_rx.v
+++ /dev/null
@@ -1,144 +0,0 @@
-//
-// Copyright 2011 Ettus Research LLC
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program 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 General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program.  If not, see <http://www.gnu.org/licenses/>.
-//
-
-
-module dsp_core_rx
-  #(parameter BASE = 160)
-  (input clk, input rst,
-   input set_stb, input [7:0] set_addr, input [31:0] set_data,
-
-   input [23:0] adc_i, input adc_ovf_i,
-   input [23:0] adc_q, input adc_ovf_q,
-   
-   output [31:0] sample,
-   input run,
-   output strobe,
-   output [31:0] debug
-   );
-
-   wire [31:0] phase_inc;
-   reg [31:0]  phase;
-
-   wire [24:0] i_cordic, q_cordic;
-   wire [23:0] i_cordic_clip, q_cordic_clip;
-   wire [23:0] i_cic, q_cic;
-   wire [23:0] i_hb1, q_hb1;
-   wire [23:0] i_hb2, q_hb2;
-   
-   wire        strobe_cic, strobe_hb1, strobe_hb2;
-   wire        enable_hb1, enable_hb2;
-   wire [7:0]  cic_decim_rate;
-
-   reg [23:0]  adc_i_mux, adc_q_mux;
-   wire        realmode;
-   wire        swap_iq;
-   
-   setting_reg #(.my_addr(BASE+0)) sr_0
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out(phase_inc),.changed());
-   
-   /*
-   setting_reg #(.my_addr(BASE+1)) sr_1
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({scale_i,scale_q}),.changed());
-   */
-   
-   setting_reg #(.my_addr(BASE+2), .width(10)) sr_2
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({enable_hb1, enable_hb2, cic_decim_rate}),.changed());
-
-   setting_reg #(.my_addr(BASE+3), .width(2)) sr_3
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({realmode,swap_iq}),.changed());
-
-   // MUX so we can do realmode signals on either input
-   
-   always @(posedge clk)
-     if(swap_iq)
-       begin
-	  adc_i_mux <= adc_q;
-	  adc_q_mux <= realmode ? 24'd0 : adc_i;
-       end
-     else
-       begin
-	  adc_i_mux <= adc_i;
-	  adc_q_mux <= realmode ? 24'd0 : adc_q;
-       end
-
-   // NCO
-   always @(posedge clk)
-     if(rst)
-       phase <= 0;
-     else if(~run)
-       phase <= 0;
-     else
-       phase <= phase + phase_inc;
-
-   // CORDIC  24-bit I/O
-   cordic_z24 #(.bitwidth(25))
-     cordic(.clock(clk), .reset(rst), .enable(run),
-	    .xi({adc_i_mux[23],adc_i_mux}),. yi({adc_q_mux[23],adc_q_mux}), .zi(phase[31:8]),
-	    .xo(i_cordic),.yo(q_cordic),.zo() );
-
-   clip_reg #(.bits_in(25), .bits_out(24)) clip_i
-     (.clk(clk), .in(i_cordic), .strobe_in(1'b1), .out(i_cordic_clip));
-   clip_reg #(.bits_in(25), .bits_out(24)) clip_q
-     (.clk(clk), .in(q_cordic), .strobe_in(1'b1), .out(q_cordic_clip));
-
-   // CIC decimator  24 bit I/O
-   cic_strober cic_strober(.clock(clk),.reset(rst),.enable(run),.rate(cic_decim_rate),
-			   .strobe_fast(1),.strobe_slow(strobe_cic) );
-
-   cic_decim #(.bw(24))
-     decim_i (.clock(clk),.reset(rst),.enable(run),
-	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
-	      .signal_in(i_cordic_clip),.signal_out(i_cic));
-   
-   cic_decim #(.bw(24))
-     decim_q (.clock(clk),.reset(rst),.enable(run),
-	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
-	      .signal_in(q_cordic_clip),.signal_out(q_cic));
-
-   // First (small) halfband  24 bit I/O
-   small_hb_dec #(.WIDTH(24)) small_hb_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
-      .stb_in(strobe_cic),.data_in(i_cic),.stb_out(strobe_hb1),.data_out(i_hb1));
-   
-   small_hb_dec #(.WIDTH(24)) small_hb_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
-      .stb_in(strobe_cic),.data_in(q_cic),.stb_out(),.data_out(q_hb1));
-
-   // Second (large) halfband  24 bit I/O
-   wire [8:0]  cpi_hb = enable_hb1 ? {cic_decim_rate,1'b0} : {1'b0,cic_decim_rate};
-   hb_dec #(.WIDTH(24)) hb_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
-      .stb_in(strobe_hb1),.data_in(i_hb1),.stb_out(strobe_hb2),.data_out(i_hb2));
-
-   hb_dec #(.WIDTH(24)) hb_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
-      .stb_in(strobe_hb1),.data_in(q_hb1),.stb_out(),.data_out(q_hb2));
-
-   // Round final answer to 16 bits
-   round_sd #(.WIDTH_IN(24),.WIDTH_OUT(16)) round_i
-     (.clk(clk),.reset(rst), .in(i_hb2),.strobe_in(strobe_hb2), .out(sample[31:16]), .strobe_out(strobe));
-
-   round_sd #(.WIDTH_IN(24),.WIDTH_OUT(16)) round_q
-     (.clk(clk),.reset(rst), .in(q_hb2),.strobe_in(strobe_hb2), .out(sample[15:0]), .strobe_out());
-   
-   assign      debug = {enable_hb1, enable_hb2, run, strobe, strobe_cic, strobe_hb1, strobe_hb2};
-   
-endmodule // dsp_core_rx
diff --git a/fpga/usrp2/sdr_lib/dsp_core_rx_old.v b/fpga/usrp2/sdr_lib/dsp_core_rx_old.v
deleted file mode 100644
index 90d5d839f..000000000
--- a/fpga/usrp2/sdr_lib/dsp_core_rx_old.v
+++ /dev/null
@@ -1,200 +0,0 @@
-//
-// Copyright 2011 Ettus Research LLC
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program 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 General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program.  If not, see <http://www.gnu.org/licenses/>.
-//
-
-
-`define DSP_CORE_RX_BASE 160
-module dsp_core_rx_old
-  (input clk, input rst,
-   input set_stb, input [7:0] set_addr, input [31:0] set_data,
-
-   input [13:0] adc_a, input adc_ovf_a,
-   input [13:0] adc_b, input adc_ovf_b,
-   
-   input [15:0] io_rx,
-
-   output [31:0] sample,
-   input run,
-   output strobe,
-   output [31:0] debug
-   );
-
-   wire [15:0] scale_i, scale_q;
-   wire [13:0] adc_a_ofs, adc_b_ofs;
-   reg [13:0] adc_i, adc_q;
-   wire [31:0] phase_inc;
-   reg [31:0]  phase;
-
-   wire [35:0] prod_i, prod_q;
-   wire [23:0] i_cordic, q_cordic;
-   wire [23:0] i_cic, q_cic;
-   wire [17:0] i_cic_scaled, q_cic_scaled;
-   wire [17:0] i_hb1, q_hb1;
-   wire [17:0] i_hb2, q_hb2;
-   wire [15:0] i_out, q_out;
-
-   wire        strobe_cic, strobe_hb1, strobe_hb2;
-   wire        enable_hb1, enable_hb2;
-   wire [7:0]  cic_decim_rate;
-
-   wire [31:10] UNUSED_1;
-   wire [31:4] 	UNUSED_2;
-   wire [31:2] 	UNUSED_3;
-   
-   setting_reg #(.my_addr(`DSP_CORE_RX_BASE+0)) sr_0
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out(phase_inc),.changed());
-   
-   setting_reg #(.my_addr(`DSP_CORE_RX_BASE+1)) sr_1
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({scale_i,scale_q}),.changed());
-   
-   setting_reg #(.my_addr(`DSP_CORE_RX_BASE+2)) sr_2
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({UNUSED_1, enable_hb1, enable_hb2, cic_decim_rate}),.changed());
-
-   rx_dcoffset #(.WIDTH(14),.ADDR(`DSP_CORE_RX_BASE+6)) rx_dcoffset_a
-     (.clk(clk),.rst(rst),.set_stb(set_stb),.set_addr(set_addr),.set_data(set_data),
-      .adc_in(adc_a),.adc_out(adc_a_ofs));
-   
-   rx_dcoffset #(.WIDTH(14),.ADDR(`DSP_CORE_RX_BASE+7)) rx_dcoffset_b
-     (.clk(clk),.rst(rst),.set_stb(set_stb),.set_addr(set_addr),.set_data(set_data),
-      .adc_in(adc_b),.adc_out(adc_b_ofs));
-
-   wire [3:0]  muxctrl;
-   setting_reg #(.my_addr(`DSP_CORE_RX_BASE+8)) sr_8
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({UNUSED_2,muxctrl}),.changed());
-
-   wire [1:0] gpio_ena;
-   setting_reg #(.my_addr(`DSP_CORE_RX_BASE+9)) sr_9
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({UNUSED_3,gpio_ena}),.changed());
-
-   // The TVRX connects to what is called adc_b, thus A and B are
-   // swapped throughout the design.
-   //
-   // In the interest of expediency and keeping the s/w sane, we just remap them here.
-   // The I & Q fields are mapped the same:
-   // 0 -> "the real A" (as determined by the TVRX)
-   // 1 -> "the real B"
-   // 2 -> const zero
-   
-   always @(posedge clk)
-     case(muxctrl[1:0])		// The I mapping
-       0: adc_i <= adc_b_ofs;	// "the real A"
-       1: adc_i <= adc_a_ofs;
-       2: adc_i <= 0;
-       default: adc_i <= 0;
-     endcase // case(muxctrl[1:0])
-          
-   always @(posedge clk)
-     case(muxctrl[3:2])		// The Q mapping
-       0: adc_q <= adc_b_ofs;	// "the real A"
-       1: adc_q <= adc_a_ofs;
-       2: adc_q <= 0;
-       default: adc_q <= 0;
-     endcase // case(muxctrl[3:2])
-       
-   always @(posedge clk)
-     if(rst)
-       phase <= 0;
-     else if(~run)
-       phase <= 0;
-     else
-       phase <= phase + phase_inc;
-
-   MULT18X18S mult_i
-     (.P(prod_i),    // 36-bit multiplier output
-      .A({{4{adc_i[13]}},adc_i} ),    // 18-bit multiplier input
-      .B({{2{scale_i[15]}},scale_i}),    // 18-bit multiplier input
-      .C(clk),    // Clock input
-      .CE(1),  // Clock enable input
-      .R(rst)     // Synchronous reset input
-      );
-
-   MULT18X18S mult_q
-     (.P(prod_q),    // 36-bit multiplier output
-      .A({{4{adc_q[13]}},adc_q} ),    // 18-bit multiplier input
-      .B({{2{scale_q[15]}},scale_q}),    // 18-bit multiplier input
-      .C(clk),    // Clock input
-      .CE(1),  // Clock enable input
-      .R(rst)     // Synchronous reset input
-      ); 
-
-   
-   cordic_z24 #(.bitwidth(24))
-     cordic(.clock(clk), .reset(rst), .enable(run),
-	    .xi(prod_i[23:0]),. yi(prod_q[23:0]), .zi(phase[31:8]),
-	    .xo(i_cordic),.yo(q_cordic),.zo() );
-
-   cic_strober cic_strober(.clock(clk),.reset(rst),.enable(run),.rate(cic_decim_rate),
-			   .strobe_fast(1),.strobe_slow(strobe_cic) );
-
-   cic_decim #(.bw(24))
-     decim_i (.clock(clk),.reset(rst),.enable(run),
-	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
-	      .signal_in(i_cordic),.signal_out(i_cic));
-   
-   cic_decim #(.bw(24))
-     decim_q (.clock(clk),.reset(rst),.enable(run),
-	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
-	      .signal_in(q_cordic),.signal_out(q_cic));
-
-   round_reg #(.bits_in(24),.bits_out(18)) round_icic (.clk(clk),.in(i_cic),.out(i_cic_scaled));
-   round_reg #(.bits_in(24),.bits_out(18)) round_qcic (.clk(clk),.in(q_cic),.out(q_cic_scaled));
-   reg 	       strobe_cic_d1;
-   always @(posedge clk) strobe_cic_d1 <= strobe_cic;
-   
-   small_hb_dec #(.WIDTH(18)) small_hb_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
-      .stb_in(strobe_cic_d1),.data_in(i_cic_scaled),.stb_out(strobe_hb1),.data_out(i_hb1));
-   
-   small_hb_dec #(.WIDTH(18)) small_hb_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
-      .stb_in(strobe_cic_d1),.data_in(q_cic_scaled),.stb_out(),.data_out(q_hb1));
-
-   wire [8:0]  cpi_hb = enable_hb1 ? {cic_decim_rate,1'b0} : {1'b0,cic_decim_rate};
-   hb_dec #(.IWIDTH(18), .OWIDTH(18), .CWIDTH(18), .ACCWIDTH(24)) hb_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
-      .stb_in(strobe_hb1),.data_in(i_hb1),.stb_out(strobe_hb2),.data_out(i_hb2));
-
-   hb_dec #(.IWIDTH(18), .OWIDTH(18), .CWIDTH(18), .ACCWIDTH(24)) hb_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
-      .stb_in(strobe_hb1),.data_in(q_hb1),.stb_out(),.data_out(q_hb2));
-
-   round #(.bits_in(18),.bits_out(16)) round_iout (.in(i_hb2),.out(i_out));
-   round #(.bits_in(18),.bits_out(16)) round_qout (.in(q_hb2),.out(q_out));
-
-   // Streaming GPIO
-   //
-   // io_rx[15] => I channel LSB if gpio_ena[0] high
-   // io_rx[14] => Q channel LSB if gpio_ena[1] high
-
-   reg [31:0] sample_reg;
-   always @(posedge clk)
-     begin
-	sample_reg[31:17] <= i_out[15:1];
-	sample_reg[15:1]  <= q_out[15:1];
-	sample_reg[16]    <= gpio_ena[0] ? io_rx[15] : i_out[0]; 
-	sample_reg[0]     <= gpio_ena[1] ? io_rx[14] : q_out[0];
-     end
-   
-   assign      sample = sample_reg;
-   assign      strobe = strobe_hb2;
-   assign      debug = {enable_hb1, enable_hb2, run, strobe, strobe_cic, strobe_cic_d1, strobe_hb1, strobe_hb2};
-   
-endmodule // dsp_core_rx
diff --git a/fpga/usrp2/sdr_lib/dsp_core_rx_tb.v b/fpga/usrp2/sdr_lib/dsp_core_rx_tb.v
index 271db8cef..a221bed44 100644
--- a/fpga/usrp2/sdr_lib/dsp_core_rx_tb.v
+++ b/fpga/usrp2/sdr_lib/dsp_core_rx_tb.v
@@ -1,6 +1,6 @@
 
 `timescale 1ns/1ns
-module dsp_core_rx_tb();
+module ddc_chain_tb();
    
    reg clk, rst;
 
@@ -9,8 +9,8 @@ module dsp_core_rx_tb();
    initial clk = 0;
    always #5 clk = ~clk;
    
-   initial $dumpfile("dsp_core_rx_tb.vcd");
-   initial $dumpvars(0,dsp_core_rx_tb);
+   initial $dumpfile("ddc_chain_tb.vcd");
+   initial $dumpvars(0,ddc_chain_tb);
    
    reg signed [23:0] adc_in;
    wire signed [15:0] adc_out_i, adc_out_q;
@@ -27,7 +27,7 @@ module dsp_core_rx_tb();
    reg [7:0] set_addr;
    reg [31:0] set_data;
    
-   dsp_core_rx #(.BASE(0)) dsp_core_rx
+   ddc_chain #(.BASE(0)) ddc_chain
      (.clk(clk),.rst(rst),
       .set_stb(set_stb),.set_addr(set_addr),.set_data(set_data),
       .adc_i(adc_in), .adc_ovf_i(0),
@@ -70,4 +70,4 @@ module dsp_core_rx_tb();
        adc_in <= adc_in + 4;
    //adc_in <= (($random % 473) + 23)/4;
 */   
-endmodule // dsp_core_rx_tb
+endmodule // ddc_chain_tb
diff --git a/fpga/usrp2/sdr_lib/dsp_core_rx_udp.v b/fpga/usrp2/sdr_lib/dsp_core_rx_udp.v
deleted file mode 100644
index 08dab37e6..000000000
--- a/fpga/usrp2/sdr_lib/dsp_core_rx_udp.v
+++ /dev/null
@@ -1,200 +0,0 @@
-//
-// Copyright 2011 Ettus Research LLC
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program 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 General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program.  If not, see <http://www.gnu.org/licenses/>.
-//
-
-
-module dsp_core_rx
-  #(parameter BASE = 160)
-  (input clk, input rst,
-   input set_stb, input [7:0] set_addr, input [31:0] set_data,
-
-   input [13:0] adc_a, input adc_ovf_a,
-   input [13:0] adc_b, input adc_ovf_b,
-   
-   input [15:0] io_rx,
-
-   output [31:0] sample,
-   input run,
-   output strobe,
-   output [31:0] debug
-   );
-
-   wire [15:0] scale_i, scale_q;
-   wire [13:0] adc_a_ofs, adc_b_ofs;
-   reg [13:0] adc_i, adc_q;
-   wire [31:0] phase_inc;
-   reg [31:0]  phase;
-
-   wire [35:0] prod_i, prod_q;
-   wire [23:0] i_cordic, q_cordic;
-   wire [23:0] i_cic, q_cic;
-   wire [17:0] i_cic_scaled, q_cic_scaled;
-   wire [17:0] i_hb1, q_hb1;
-   wire [17:0] i_hb2, q_hb2;
-   wire [15:0] i_out, q_out;
-
-   wire        strobe_cic, strobe_hb1, strobe_hb2;
-   wire        enable_hb1, enable_hb2;
-   wire [7:0]  cic_decim_rate;
-
-   wire [31:10] UNUSED_1;
-   wire [31:4] 	UNUSED_2;
-   wire [31:2] 	UNUSED_3;
-   
-   setting_reg #(.my_addr(BASE+0)) sr_0
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out(phase_inc),.changed());
-   
-   setting_reg #(.my_addr(BASE+1)) sr_1
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({scale_i,scale_q}),.changed());
-   
-   setting_reg #(.my_addr(BASE+2)) sr_2
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({UNUSED_1, enable_hb1, enable_hb2, cic_decim_rate}),.changed());
-
-   rx_dcoffset #(.WIDTH(14),.ADDR(BASE+3)) rx_dcoffset_a
-     (.clk(clk),.rst(rst),.set_stb(set_stb),.set_addr(set_addr),.set_data(set_data),
-      .adc_in(adc_a),.adc_out(adc_a_ofs));
-   
-   rx_dcoffset #(.WIDTH(14),.ADDR(BASE+4)) rx_dcoffset_b
-     (.clk(clk),.rst(rst),.set_stb(set_stb),.set_addr(set_addr),.set_data(set_data),
-      .adc_in(adc_b),.adc_out(adc_b_ofs));
-
-   wire [3:0]  muxctrl;
-   setting_reg #(.my_addr(BASE+5)) sr_8
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({UNUSED_2,muxctrl}),.changed());
-
-   wire [1:0] gpio_ena;
-   setting_reg #(.my_addr(BASE+6)) sr_9
-     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({UNUSED_3,gpio_ena}),.changed());
-
-   // The TVRX connects to what is called adc_b, thus A and B are
-   // swapped throughout the design.
-   //
-   // In the interest of expediency and keeping the s/w sane, we just remap them here.
-   // The I & Q fields are mapped the same:
-   // 0 -> "the real A" (as determined by the TVRX)
-   // 1 -> "the real B"
-   // 2 -> const zero
-   
-   always @(posedge clk)
-     case(muxctrl[1:0])		// The I mapping
-       0: adc_i <= adc_b_ofs;	// "the real A"
-       1: adc_i <= adc_a_ofs;
-       2: adc_i <= 0;
-       default: adc_i <= 0;
-     endcase // case(muxctrl[1:0])
-          
-   always @(posedge clk)
-     case(muxctrl[3:2])		// The Q mapping
-       0: adc_q <= adc_b_ofs;	// "the real A"
-       1: adc_q <= adc_a_ofs;
-       2: adc_q <= 0;
-       default: adc_q <= 0;
-     endcase // case(muxctrl[3:2])
-       
-   always @(posedge clk)
-     if(rst)
-       phase <= 0;
-     else if(~run)
-       phase <= 0;
-     else
-       phase <= phase + phase_inc;
-
-   MULT18X18S mult_i
-     (.P(prod_i),    // 36-bit multiplier output
-      .A({{4{adc_i[13]}},adc_i} ),    // 18-bit multiplier input
-      .B({{2{scale_i[15]}},scale_i}),    // 18-bit multiplier input
-      .C(clk),    // Clock input
-      .CE(1),  // Clock enable input
-      .R(rst)     // Synchronous reset input
-      );
-
-   MULT18X18S mult_q
-     (.P(prod_q),    // 36-bit multiplier output
-      .A({{4{adc_q[13]}},adc_q} ),    // 18-bit multiplier input
-      .B({{2{scale_q[15]}},scale_q}),    // 18-bit multiplier input
-      .C(clk),    // Clock input
-      .CE(1),  // Clock enable input
-      .R(rst)     // Synchronous reset input
-      ); 
-
-   
-   cordic_z24 #(.bitwidth(24))
-     cordic(.clock(clk), .reset(rst), .enable(run),
-	    .xi(prod_i[23:0]),. yi(prod_q[23:0]), .zi(phase[31:8]),
-	    .xo(i_cordic),.yo(q_cordic),.zo() );
-
-   cic_strober cic_strober(.clock(clk),.reset(rst),.enable(run),.rate(cic_decim_rate),
-			   .strobe_fast(1),.strobe_slow(strobe_cic) );
-
-   cic_decim #(.bw(24))
-     decim_i (.clock(clk),.reset(rst),.enable(run),
-	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
-	      .signal_in(i_cordic),.signal_out(i_cic));
-   
-   cic_decim #(.bw(24))
-     decim_q (.clock(clk),.reset(rst),.enable(run),
-	      .rate(cic_decim_rate),.strobe_in(1'b1),.strobe_out(strobe_cic),
-	      .signal_in(q_cordic),.signal_out(q_cic));
-
-   round_reg #(.bits_in(24),.bits_out(18)) round_icic (.clk(clk),.in(i_cic),.out(i_cic_scaled));
-   round_reg #(.bits_in(24),.bits_out(18)) round_qcic (.clk(clk),.in(q_cic),.out(q_cic_scaled));
-   reg 	       strobe_cic_d1;
-   always @(posedge clk) strobe_cic_d1 <= strobe_cic;
-   
-   small_hb_dec #(.WIDTH(18)) small_hb_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
-      .stb_in(strobe_cic_d1),.data_in(i_cic_scaled),.stb_out(strobe_hb1),.data_out(i_hb1));
-   
-   small_hb_dec #(.WIDTH(18)) small_hb_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
-      .stb_in(strobe_cic_d1),.data_in(q_cic_scaled),.stb_out(),.data_out(q_hb1));
-
-   wire [8:0]  cpi_hb = enable_hb1 ? {cic_decim_rate,1'b0} : {1'b0,cic_decim_rate};
-   hb_dec #(.IWIDTH(18), .OWIDTH(18), .CWIDTH(18), .ACCWIDTH(24)) hb_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
-      .stb_in(strobe_hb1),.data_in(i_hb1),.stb_out(strobe_hb2),.data_out(i_hb2));
-
-   hb_dec #(.IWIDTH(18), .OWIDTH(18), .CWIDTH(18), .ACCWIDTH(24)) hb_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
-      .stb_in(strobe_hb1),.data_in(q_hb1),.stb_out(),.data_out(q_hb2));
-
-   round #(.bits_in(18),.bits_out(16)) round_iout (.in(i_hb2),.out(i_out));
-   round #(.bits_in(18),.bits_out(16)) round_qout (.in(q_hb2),.out(q_out));
-
-   // Streaming GPIO
-   //
-   // io_rx[15] => I channel LSB if gpio_ena[0] high
-   // io_rx[14] => Q channel LSB if gpio_ena[1] high
-
-   reg [31:0] sample_reg;
-   always @(posedge clk)
-     begin
-	sample_reg[31:17] <= i_out[15:1];
-	sample_reg[15:1]  <= q_out[15:1];
-	sample_reg[16]    <= gpio_ena[0] ? io_rx[15] : i_out[0]; 
-	sample_reg[0]     <= gpio_ena[1] ? io_rx[14] : q_out[0];
-     end
-   
-   assign      sample = sample_reg;
-   assign      strobe = strobe_hb2;
-   assign      debug = {enable_hb1, enable_hb2, run, strobe, strobe_cic, strobe_cic_d1, strobe_hb1, strobe_hb2};
-   
-endmodule // dsp_core_rx
diff --git a/fpga/usrp2/sdr_lib/dsp_rx_glue.v b/fpga/usrp2/sdr_lib/dsp_rx_glue.v
new file mode 100644
index 000000000..038a67a29
--- /dev/null
+++ b/fpga/usrp2/sdr_lib/dsp_rx_glue.v
@@ -0,0 +1,98 @@
+//
+// Copyright 2012 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+//The following module effects the IO of the DDC chain.
+//By default, this entire module is a simple pass-through.
+
+module dsp_rx_glue
+#(
+    //the dsp unit number: 0, 1, 2...
+    parameter DSPNO = 0,
+
+    //frontend bus width
+    parameter WIDTH = 24
+)
+(
+    //control signals
+    input clock, input reset, input clear, input enable,
+
+    //user settings bus, controlled through user setting regs API
+    input set_stb, input [7:0] set_addr, input [31:0] set_data,
+
+    //full rate inputs directly from the RX frontend
+    input [WIDTH-1:0] frontend_i,
+    input [WIDTH-1:0] frontend_q,
+
+    //full rate outputs directly to the DDC chain
+    output [WIDTH-1:0] ddc_in_i,
+    output [WIDTH-1:0] ddc_in_q,
+
+    //strobed samples {I16,Q16} from the RX DDC chain
+    input [31:0] ddc_out_sample,
+    input ddc_out_strobe, //high on valid sample
+    output ddc_out_enable, //enables DDC module
+
+    //strobbed baseband samples {I16,Q16} from this module
+    output [31:0] bb_sample,
+    output bb_strobe, //high on valid sample
+
+    //debug output (optional)
+    output [31:0] debug
+);
+
+    generate
+        if (DSPNO==0) begin
+            `ifndef RX_DSP0_MODULE
+            assign ddc_in_i = frontend_i;
+            assign ddc_in_q = frontend_q;
+            assign bb_sample = ddc_out_sample;
+            assign bb_strobe = ddc_out_strobe;
+            assign ddc_out_enable = enable;
+            `else
+            `RX_DSP0_MODULE #(.WIDTH(WIDTH)) rx_dsp0_custom
+            (
+                .clock(clock), .reset(reset), .clear(clear), .enable(enable),
+                .set_stb(set_stb), .set_addr(set_addr), .set_data(set_data),
+                .frontend_i(frontend_i), .frontend_q(frontend_q),
+                .ddc_in_i(ddc_in_i), .ddc_in_q(ddc_in_q),
+                .ddc_out_sample(ddc_out_sample), .ddc_out_strobe(ddc_out_strobe), .ddc_out_enable(ddc_out_enable),
+                .bb_sample(bb_sample), .bb_strobe(bb_strobe)
+            );
+            `endif
+        end
+        else begin
+            `ifndef RX_DSP1_MODULE
+            assign ddc_in_i = frontend_i;
+            assign ddc_in_q = frontend_q;
+            assign bb_sample = ddc_out_sample;
+            assign bb_strobe = ddc_out_strobe;
+            assign ddc_out_enable = enable;
+            `else
+            `RX_DSP1_MODULE #(.WIDTH(WIDTH)) rx_dsp1_custom
+            (
+                .clock(clock), .reset(reset), .clear(clear), .enable(enable),
+                .set_stb(set_stb), .set_addr(set_addr), .set_data(set_data),
+                .frontend_i(frontend_i), .frontend_q(frontend_q),
+                .ddc_in_i(ddc_in_i), .ddc_in_q(ddc_in_q),
+                .ddc_out_sample(ddc_out_sample), .ddc_out_strobe(ddc_out_strobe), .ddc_out_enable(ddc_out_enable),
+                .bb_sample(bb_sample), .bb_strobe(bb_strobe)
+            );
+            `endif
+        end
+    endgenerate
+
+endmodule //dsp_rx_glue
diff --git a/fpga/usrp2/sdr_lib/dsp_tx_glue.v b/fpga/usrp2/sdr_lib/dsp_tx_glue.v
new file mode 100644
index 000000000..46f6789ee
--- /dev/null
+++ b/fpga/usrp2/sdr_lib/dsp_tx_glue.v
@@ -0,0 +1,98 @@
+//
+// Copyright 2012 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+//The following module effects the IO of the DUC chain.
+//By default, this entire module is a simple pass-through.
+
+module dsp_tx_glue
+#(
+    //the dsp unit number: 0, 1, 2...
+    parameter DSPNO = 0,
+
+    //frontend bus width
+    parameter WIDTH = 24
+)
+(
+    //control signals
+    input clock, input reset, input clear, input enable,
+
+    //user settings bus, controlled through user setting regs API
+    input set_stb, input [7:0] set_addr, input [31:0] set_data,
+
+    //full rate outputs directly to the TX frontend
+    output [WIDTH-1:0] frontend_i,
+    output [WIDTH-1:0] frontend_q,
+
+    //full rate outputs directly from the DUC chain
+    input [WIDTH-1:0] duc_out_i,
+    input [WIDTH-1:0] duc_out_q,
+
+    //strobed samples {I16,Q16} to the TX DUC chain
+    output [31:0] duc_in_sample,
+    input duc_in_strobe, //this is a backpressure signal
+    output duc_in_enable, //enables DUC module
+
+    //strobbed baseband samples {I16,Q16} to this module
+    input [31:0] bb_sample,
+    output bb_strobe, //this is a backpressure signal
+
+    //debug output (optional)
+    output [31:0] debug
+);
+
+    generate
+        if (DSPNO==0) begin
+            `ifndef TX_DSP0_MODULE
+            assign frontend_i = duc_out_i;
+            assign frontend_q = duc_out_q;
+            assign duc_in_sample = bb_sample;
+            assign bb_strobe = duc_in_strobe;
+            assign duc_in_enable = enable;
+            `else
+            `TX_DSP0_MODULE #(.WIDTH(WIDTH)) tx_dsp0_custom
+            (
+                .clock(clock), .reset(reset), .clear(clear), .enable(enable),
+                .set_stb(set_stb), .set_addr(set_addr), .set_data(set_data),
+                .frontend_i(frontend_i), .frontend_q(frontend_q),
+                .duc_out_i(duc_out_i), .duc_out_q(duc_out_q),
+                .duc_in_sample(duc_in_sample), .duc_in_strobe(duc_in_strobe), .duc_in_enable(duc_in_enable),
+                .bb_sample(bb_sample), .bb_strobe(bb_strobe)
+            );
+            `endif
+        end
+        else begin
+            `ifndef TX_DSP1_MODULE
+            assign frontend_i = duc_out_i;
+            assign frontend_q = duc_out_q;
+            assign duc_in_sample = bb_sample;
+            assign bb_strobe = duc_in_strobe;
+            assign duc_in_enable = enable;
+            `else
+            `TX_DSP1_MODULE #(.WIDTH(WIDTH)) tx_dsp1_custom
+            (
+                .clock(clock), .reset(reset), .clear(clear), .enable(enable),
+                .set_stb(set_stb), .set_addr(set_addr), .set_data(set_data),
+                .frontend_i(frontend_i), .frontend_q(frontend_q),
+                .duc_out_i(duc_out_i), .duc_out_q(duc_out_q),
+                .duc_in_sample(duc_in_sample), .duc_in_strobe(duc_in_strobe), .duc_in_enable(duc_in_enable),
+                .bb_sample(bb_sample), .bb_strobe(bb_strobe)
+            );
+            `endif
+        end
+    endgenerate
+
+endmodule //dsp_tx_glue
diff --git a/fpga/usrp2/sdr_lib/dspengine_16to8.v b/fpga/usrp2/sdr_lib/dspengine_16to8.v
index 53c5d29da..448c57d35 100644
--- a/fpga/usrp2/sdr_lib/dspengine_16to8.v
+++ b/fpga/usrp2/sdr_lib/dspengine_16to8.v
@@ -1,5 +1,5 @@
 
-// Copyright 2011 Ettus Research LLC
+// Copyright 2011-2012 Ettus Research LLC
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
@@ -32,13 +32,11 @@ module dspengine_16to8
     input [35:0] access_dat_i
     );
 
-   wire 	 convert;
-   wire [17:0] 	 scale_factor;
-   
-   setting_reg #(.my_addr(BASE),.width(19)) sr_16to8
+   wire convert;
+   setting_reg #(.my_addr(BASE),.width(1)) sr_16to8
      (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({convert,scale_factor}),.changed());
-   
+      .in(set_data),.out(convert),.changed());
+
    reg [2:0] 	 dsp_state;
    localparam DSP_IDLE = 0;
    localparam DSP_PARSE_HEADER = 1;
@@ -63,7 +61,7 @@ module dspengine_16to8
    wire [15:0] 	 scaled_i, scaled_q;
    wire [7:0] 	 i8, q8;
    reg [7:0] 	 i8_reg, q8_reg;
-   wire 	 stb_read, stb_mult, stb_clip, stb_round, val_read, val_mult, val_clip, val_round;
+   wire 	 stb_read, stb_clip, val_read, val_clip;
    wire 	 stb_out, stb_reg;
    reg 		 even;
    
@@ -193,29 +191,21 @@ module dspengine_16to8
    wire [15:0] i16 = access_dat_i[31:16];
    wire [15:0] q16 = access_dat_i[15:0];
 
-   pipectrl #(.STAGES(4), .TAGWIDTH(2)) pipectrl 
+   pipectrl #(.STAGES(2), .TAGWIDTH(2)) pipectrl
      (.clk(clk), .reset(reset),
       .src_rdy_i(send_to_pipe), .dst_rdy_o(), // dst_rdy_o will always be 1 since dst_rdy_i is 1, below
       .src_rdy_o(stb_out), .dst_rdy_i(1),   // always accept output of chain
-      .strobes({stb_round,stb_clip,stb_mult,stb_read}), .valids({val_round,val_clip,val_mult,val_read}),
+      .strobes({stb_clip,stb_read}), .valids({val_clip,val_read}),
       .tag_i({last,even}), .tag_o({last_o,even_o}));
 
    always @(posedge clk)
      if(stb_out & ~even_o)
        {i8_reg,q8_reg} <= {i8,q8};
-   
-   MULT18X18S mult_i 
-     (.P(prod_i), .A(scale_factor), .B({i16,2'b00}), .C(clk), .CE(stb_mult), .R(reset) ); 
-   clip_reg #(.bits_in(24),.bits_out(16),.STROBED(1)) clip_i 
-     (.clk(clk), .in(prod_i[35:12]), .out(scaled_i), .strobe_in(stb_clip), .strobe_out());
-   round_sd #(.WIDTH_IN(16),.WIDTH_OUT(8),.DISABLE_SD(1)) round_i
-     (.clk(clk), .reset(reset), .in(scaled_i), .strobe_in(stb_round), .out(i8), .strobe_out());
-
-   MULT18X18S mult_q 
-     (.P(prod_q), .A(scale_factor), .B({q16,2'b00}), .C(clk), .CE(stb_mult), .R(reset) ); 
-   clip_reg #(.bits_in(24),.bits_out(16),.STROBED(1)) clip_q 
-     (.clk(clk), .in(prod_q[35:12]), .out(scaled_q), .strobe_in(stb_clip), .strobe_out());
-   round_sd #(.WIDTH_IN(16),.WIDTH_OUT(8),.DISABLE_SD(1)) round_q
-     (.clk(clk), .reset(reset), .in(scaled_q), .strobe_in(stb_round), .out(q8), .strobe_out());
+
+   clip_reg #(.bits_in(16),.bits_out(8),.STROBED(1)) clip_i
+     (.clk(clk), .in(i16), .out(i8), .strobe_in(stb_clip), .strobe_out());
+
+   clip_reg #(.bits_in(16),.bits_out(8),.STROBED(1)) clip_q
+     (.clk(clk), .in(q16), .out(q8), .strobe_in(stb_clip), .strobe_out());
 
 endmodule // dspengine_16to8
diff --git a/fpga/usrp2/sdr_lib/dspengine_8to16.v b/fpga/usrp2/sdr_lib/dspengine_8to16.v
new file mode 100644
index 000000000..85187d78d
--- /dev/null
+++ b/fpga/usrp2/sdr_lib/dspengine_8to16.v
@@ -0,0 +1,203 @@
+
+// Copyright 2012 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+module dspengine_8to16
+  #(parameter BASE = 0,
+    parameter BUF_SIZE = 9,
+    parameter HEADER_OFFSET = 0)
+   (input clk, input reset, input clear,
+    input set_stb, input [7:0] set_addr, input [31:0] set_data,
+
+    output access_we,
+    output access_stb,
+    input access_ok,
+    output access_done,
+    output access_skip_read,
+    output [BUF_SIZE-1:0] access_adr,
+    input [BUF_SIZE-1:0] access_len,
+    output [35:0] access_dat_o,
+    input [35:0] access_dat_i
+    );
+
+   wire 	 convert;
+   
+   setting_reg #(.my_addr(BASE),.width(1)) sr_8to16
+     (.clk(clk),.rst(reset),.strobe(set_stb),.addr(set_addr),
+      .in(set_data),.out(convert),.changed());
+   
+   reg [3:0] 	 dsp_state;
+   localparam DSP_IDLE = 0;
+   localparam DSP_IDLE_RD = 1;
+   localparam DSP_PARSE_HEADER = 2;
+   localparam DSP_READ = 3;
+   localparam DSP_READ_WAIT = 4;
+   localparam DSP_WRITE_1 = 5;
+   localparam DSP_WRITE_0 = 6;
+   localparam DSP_READ_TRAILER = 7;
+   localparam DSP_WRITE_TRAILER = 8;
+   localparam DSP_WRITE_HEADER = 9;
+   localparam DSP_DONE = 10;
+   
+   // Parse VITA header
+   wire 	 is_if_data = (access_dat_i[31:29] == 3'b000);
+   wire 	 has_streamid = access_dat_i[28];
+   wire 	 has_classid = access_dat_i[27];
+   wire 	 has_trailer = access_dat_i[26];
+   // 25:24 reserved, aka SOB/EOB
+   wire 	 has_secs = |access_dat_i[23:22];
+   wire 	 has_tics = |access_dat_i[21:20];
+   wire [3:0] 	 hdr_length = 1 + has_streamid + has_classid + has_classid + has_secs + has_tics + has_tics;
+   reg [15:0] 	 hdr_length_reg;
+ 	 
+   reg 		 odd;
+   
+   reg [BUF_SIZE-1:0] read_adr, write_adr;
+   reg 		      has_trailer_reg;
+   
+   reg [31:0] 	      new_header, new_trailer, trailer_mask;
+   reg 		      wait_for_trailer;
+   reg [15:0] 	      data_in_len;
+   wire       	      is_odd = access_dat_i[22] & access_dat_i[10];
+   wire [15:0] 	      data_in_lenx2 = {data_in_len[14:0], 1'b0} - is_odd;
+
+   reg [7:0] 	      i8_0, q8_0;
+   wire [7:0] 	      i8_1 = access_dat_i[31:24];
+   wire [7:0] 	      q8_1 = access_dat_i[23:16];
+   reg 		      skip;
+   
+
+   always @(posedge clk)
+     { i8_0, q8_0 } <= access_dat_i[15:0];
+   
+   always @(posedge clk)
+     if(reset | clear)
+       dsp_state <= DSP_IDLE;
+     else
+       case(dsp_state)
+	 DSP_IDLE :
+	   begin
+	      read_adr <= HEADER_OFFSET;
+	      write_adr <= HEADER_OFFSET;
+	      if(access_ok)
+		dsp_state <= DSP_IDLE_RD;
+	   end
+
+	 DSP_IDLE_RD: //extra idle state for read to become valid
+		dsp_state <= DSP_PARSE_HEADER;
+
+	 DSP_PARSE_HEADER :
+	   begin
+	      has_trailer_reg <= has_trailer;
+	      new_header[31:0] <= access_dat_i[31:0];
+	      hdr_length_reg <= hdr_length;
+	      if(~is_if_data | ~convert | ~has_trailer)
+		// ~convert is valid (16 bit mode) but both ~trailer and ~is_if_data are both
+		// really error conditions on the TX side.  We shouldn't ever see them in the TX chain
+		dsp_state <= DSP_WRITE_HEADER;  
+	      else
+		begin
+		   read_adr <= access_dat_i[15:0] + HEADER_OFFSET - 1; // point to trailer
+		   dsp_state <= DSP_READ_TRAILER;
+		   wait_for_trailer <= 0;
+		   data_in_len <= access_dat_i[15:0] - hdr_length - 1 /*trailer*/;
+		end
+	   end
+	 
+	 DSP_READ_TRAILER :
+	   begin
+	      wait_for_trailer <= 1;
+	      if(wait_for_trailer)
+		dsp_state <= DSP_WRITE_TRAILER;
+	      new_trailer <= access_dat_i[31:0]; // Leave trailer unchanged
+	      odd <= is_odd;
+	      write_adr <= hdr_length_reg + data_in_lenx2 + HEADER_OFFSET;
+	   end
+
+	 DSP_WRITE_TRAILER :
+	   begin
+	      dsp_state <= DSP_READ;
+	      write_adr <= write_adr - 1;
+	      read_adr <= read_adr - 1;
+	      new_header[15:0] <= write_adr + (1 - HEADER_OFFSET); // length = addr of trailer + 1
+	   end
+
+	 DSP_READ :
+	   begin
+	      read_adr <= read_adr - 1;
+	      if(odd)
+		dsp_state <= DSP_READ_WAIT;
+	      else
+		dsp_state <= DSP_WRITE_1;
+	      odd <= 0;
+	   end
+
+	 DSP_READ_WAIT :
+	   dsp_state <= DSP_WRITE_0;
+	 
+	 DSP_WRITE_1 :
+	   begin
+	      write_adr <= write_adr - 1;
+	      if(write_adr == (hdr_length_reg+HEADER_OFFSET))
+		begin
+		   write_adr <= HEADER_OFFSET;
+		   dsp_state <= DSP_WRITE_HEADER;
+		end
+	      dsp_state <= DSP_WRITE_0;
+	   end
+
+	 DSP_WRITE_0 :
+	   begin
+	      write_adr <= write_adr - 1;
+	      if(write_adr == (hdr_length_reg+HEADER_OFFSET))
+		begin
+		   write_adr <= HEADER_OFFSET;
+		   dsp_state <= DSP_WRITE_HEADER;
+		end
+	      else
+		dsp_state <= DSP_READ;
+	   end
+
+	 DSP_WRITE_HEADER :
+	   dsp_state <= DSP_DONE;
+
+	 DSP_DONE :
+	   begin
+	      read_adr <= HEADER_OFFSET;
+	      write_adr <= HEADER_OFFSET;
+	      dsp_state <= DSP_IDLE;
+	   end
+       endcase // case (dsp_state)
+
+   assign access_skip_read = 0;
+   assign access_done = (dsp_state == DSP_DONE);
+
+   assign access_stb = 1;
+
+   assign access_we = (dsp_state == DSP_WRITE_HEADER) | 
+		      (dsp_state == DSP_WRITE_TRAILER) |
+		      (dsp_state == DSP_WRITE_0) |
+		      (dsp_state == DSP_WRITE_1);
+   
+   assign access_dat_o = (dsp_state == DSP_WRITE_HEADER) ? { 4'h0, new_header } :
+			 (dsp_state == DSP_WRITE_TRAILER) ? { 4'h2, new_trailer } :
+			 (dsp_state == DSP_WRITE_0) ? { 4'h0, i8_0, 8'd0, q8_0, 8'd0 } :
+			 (dsp_state == DSP_WRITE_1) ? { 4'h0, i8_1, 8'd0, q8_1, 8'd0 } :
+			 34'h0DEADBEEF;
+         
+   assign access_adr = access_we ? write_adr : read_adr;
+      
+endmodule // dspengine_16to8
diff --git a/fpga/usrp2/sdr_lib/dsp_core_tx.v b/fpga/usrp2/sdr_lib/duc_chain.v
index 4e0163e0a..bd3402a1f 100644
--- a/fpga/usrp2/sdr_lib/dsp_core_tx.v
+++ b/fpga/usrp2/sdr_lib/duc_chain.v
@@ -1,5 +1,5 @@
 //
-// Copyright 2011 Ettus Research LLC
+// Copyright 2011-2012 Ettus Research LLC
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
@@ -15,26 +15,35 @@
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
 
+//! The USRP digital up-conversion chain
 
-module dsp_core_tx
-  #(parameter BASE=0)
-  (input clk, input rst,
+module duc_chain
+  #(
+    parameter BASE = 0,
+    parameter DSPNO = 0,
+    parameter WIDTH = 24
+  )
+  (input clk, input rst, input clr,
    input set_stb, input [7:0] set_addr, input [31:0] set_data,
+   input set_stb_user, input [7:0] set_addr_user, input [31:0] set_data_user,
 
-   output [23:0] tx_i, output [23:0] tx_q,
+   // To TX frontend
+   output [WIDTH-1:0] tx_fe_i,
+   output [WIDTH-1:0] tx_fe_q,
 
-   // To tx_control
+   // From TX control
    input [31:0] sample,
    input run,
    output strobe,
    output [31:0] debug
    );
 
-   wire [15:0] i, q, scale_i, scale_q;
+   wire duc_enb;
+   wire [17:0] scale_factor;
    wire [31:0] phase_inc;
    reg [31:0]  phase;
    wire [7:0]  interp_rate;
-   wire [3:0]  dacmux_a, dacmux_b;
+   wire [3:0]  tx_femux_a, tx_femux_b;
    wire        enable_hb1, enable_hb2;
    wire        rate_change;
    
@@ -42,9 +51,9 @@ module dsp_core_tx
      (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
       .in(set_data),.out(phase_inc),.changed());
 
-   setting_reg #(.my_addr(BASE+1)) sr_1
+   setting_reg #(.my_addr(BASE+1), .width(18)) sr_1
      (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
-      .in(set_data),.out({scale_i,scale_q}),.changed());
+      .in(set_data),.out(scale_factor),.changed());
    
    setting_reg #(.my_addr(BASE+2), .width(10)) sr_2
      (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
@@ -57,13 +66,13 @@ module dsp_core_tx
    reg 	       strobe_hb2 = 1;
    
    cic_strober #(.WIDTH(8))
-     cic_strober(.clock(clk),.reset(rst),.enable(run & ~rate_change),.rate(interp_rate),
+     cic_strober(.clock(clk),.reset(rst),.enable(duc_enb & ~rate_change),.rate(interp_rate),
 		 .strobe_fast(1),.strobe_slow(strobe_cic_pre) );
    cic_strober #(.WIDTH(2))
-     hb2_strober(.clock(clk),.reset(rst),.enable(run & ~rate_change),.rate(enable_hb2 ? 2 : 1),
+     hb2_strober(.clock(clk),.reset(rst),.enable(duc_enb & ~rate_change),.rate(enable_hb2 ? 2 : 1),
 		 .strobe_fast(strobe_cic_pre),.strobe_slow(strobe_hb2_pre) );
    cic_strober #(.WIDTH(2))
-     hb1_strober(.clock(clk),.reset(rst),.enable(run & ~rate_change),.rate(enable_hb1 ? 2 : 1),
+     hb1_strober(.clock(clk),.reset(rst),.enable(duc_enb & ~rate_change),.rate(enable_hb1 ? 2 : 1),
 		 .strobe_fast(strobe_hb2_pre),.strobe_slow(strobe_hb1_pre) );
    
    always @(posedge clk) strobe_hb1 <= strobe_hb1_pre;
@@ -74,7 +83,7 @@ module dsp_core_tx
    always @(posedge clk)
      if(rst)
        phase <= 0;
-     else if(~run)
+     else if(~duc_enb)
        phase <= 0;
      else
        phase <= phase + phase_inc;
@@ -82,8 +91,8 @@ module dsp_core_tx
    wire        signed [17:0] da, db;
    wire        signed [35:0] prod_i, prod_q;
 
-   wire [17:0] bb_i = {sample[31:16],2'b0};
-   wire [17:0] bb_q = {sample[15:0],2'b0};
+   wire [15:0] bb_i;
+   wire [15:0] bb_q;
    wire [17:0] i_interp, q_interp;
 
    wire [17:0] hb1_i, hb1_q, hb2_i, hb2_q;
@@ -92,10 +101,10 @@ module dsp_core_tx
    // Note that max CIC rate is 128, which would give an overflow on cpo if enable_hb2 is true,
    //   but the default case inside hb_interp handles this
    
-   hb_interp #(.IWIDTH(18),.OWIDTH(18),.ACCWIDTH(24)) hb_interp_i
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.cpo(cpo),.stb_in(strobe_hb1),.data_in(bb_i),.stb_out(strobe_hb2),.data_out(hb1_i));
-   hb_interp #(.IWIDTH(18),.OWIDTH(18),.ACCWIDTH(24)) hb_interp_q
-     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.cpo(cpo),.stb_in(strobe_hb1),.data_in(bb_q),.stb_out(strobe_hb2),.data_out(hb1_q));
+   hb_interp #(.IWIDTH(18),.OWIDTH(18),.ACCWIDTH(WIDTH)) hb_interp_i
+     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.cpo(cpo),.stb_in(strobe_hb1),.data_in({bb_i, 2'b0}),.stb_out(strobe_hb2),.data_out(hb1_i));
+   hb_interp #(.IWIDTH(18),.OWIDTH(18),.ACCWIDTH(WIDTH)) hb_interp_q
+     (.clk(clk),.rst(rst),.bypass(~enable_hb1),.cpo(cpo),.stb_in(strobe_hb1),.data_in({bb_q, 2'b0}),.stb_out(strobe_hb2),.data_out(hb1_q));
    
    small_hb_int #(.WIDTH(18)) small_hb_interp_i
      (.clk(clk),.rst(rst),.bypass(~enable_hb2),.stb_in(strobe_hb2),.data_in(hb1_i),
@@ -105,24 +114,22 @@ module dsp_core_tx
       .output_rate(interp_rate),.stb_out(strobe_cic),.data_out(hb2_q));
    
    cic_interp  #(.bw(18),.N(4),.log2_of_max_rate(7))
-     cic_interp_i(.clock(clk),.reset(rst),.enable(run & ~rate_change),.rate(interp_rate),
+     cic_interp_i(.clock(clk),.reset(rst),.enable(duc_enb & ~rate_change),.rate(interp_rate),
 		  .strobe_in(strobe_cic),.strobe_out(1),
 		  .signal_in(hb2_i),.signal_out(i_interp));
    
    cic_interp  #(.bw(18),.N(4),.log2_of_max_rate(7))
-     cic_interp_q(.clock(clk),.reset(rst),.enable(run & ~rate_change),.rate(interp_rate),
+     cic_interp_q(.clock(clk),.reset(rst),.enable(duc_enb & ~rate_change),.rate(interp_rate),
 		  .strobe_in(strobe_cic),.strobe_out(1),
 		  .signal_in(hb2_q),.signal_out(q_interp));
 
-   assign      strobe = strobe_hb1;
-
-   localparam  cwidth = 24;  // was 18
+   localparam  cwidth = WIDTH;  // was 18
    localparam  zwidth = 24;  // was 16
 
    wire [cwidth-1:0] da_c, db_c;
    
    cordic_z24 #(.bitwidth(cwidth))
-     cordic(.clock(clk), .reset(rst), .enable(run),
+     cordic(.clock(clk), .reset(rst), .enable(duc_enb),
 	    .xi({i_interp,{(cwidth-18){1'b0}}}),.yi({q_interp,{(cwidth-18){1'b0}}}),
 	    .zi(phase[31:32-zwidth]),
 	    .xo(da_c),.yo(db_c),.zo() );
@@ -130,7 +137,7 @@ module dsp_core_tx
    MULT18X18S MULT18X18S_inst 
      (.P(prod_i),    // 36-bit multiplier output
       .A(da_c[cwidth-1:cwidth-18]),    // 18-bit multiplier input
-      .B({{2{scale_i[15]}},scale_i}),    // 18-bit multiplier input
+      .B(scale_factor),    // 18-bit multiplier input
       .C(clk),    // Clock input
       .CE(1),  // Clock enable input
       .R(rst)     // Synchronous reset input
@@ -139,15 +146,20 @@ module dsp_core_tx
    MULT18X18S MULT18X18S_inst_2 
      (.P(prod_q),    // 36-bit multiplier output
       .A(db_c[cwidth-1:cwidth-18]),    // 18-bit multiplier input
-      .B({{2{scale_q[15]}},scale_q}),    // 18-bit multiplier input
+      .B(scale_factor),    // 18-bit multiplier input
       .C(clk),    // Clock input
       .CE(1),  // Clock enable input
       .R(rst)     // Synchronous reset input
       );
 
-   assign tx_i = prod_i[28:5];
-   assign tx_q = prod_q[28:5];
-   
+   dsp_tx_glue #(.DSPNO(DSPNO), .WIDTH(WIDTH)) dsp_tx_glue(
+    .clock(clk), .reset(rst), .clear(clr), .enable(run),
+    .set_stb(set_stb_user), .set_addr(set_addr_user), .set_data(set_data_user),
+    .frontend_i(tx_fe_i), .frontend_q(tx_fe_q),
+    .duc_out_i(prod_i[33:34-WIDTH]), .duc_out_q(prod_q[33:34-WIDTH]),
+    .duc_in_sample({bb_i, bb_q}), .duc_in_strobe(strobe_hb1), .duc_in_enable(duc_enb),
+    .bb_sample(sample), .bb_strobe(strobe));
+
    assign      debug = {strobe_cic, strobe_hb1, strobe_hb2,run};
 
 endmodule // dsp_core
diff --git a/fpga/usrp2/sdr_lib/dummy_rx.v b/fpga/usrp2/sdr_lib/dummy_rx.v
index b22d5f896..42bbe36b2 100644
--- a/fpga/usrp2/sdr_lib/dummy_rx.v
+++ b/fpga/usrp2/sdr_lib/dummy_rx.v
@@ -76,4 +76,4 @@ module dummy_rx
        q_out <= q_out + 1;
        
    
-endmodule // dsp_core_rx
+endmodule // ddc_chain