// ***************************************************************************
// ***************************************************************************
// Copyright 2011(c) Analog Devices, Inc.
// 
// All rights reserved.
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// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
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// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// ***************************************************************************
// ***************************************************************************
// ***************************************************************************
// ***************************************************************************
// This interface includes both the transmit and receive components -
// They both uses the same clock (sourced from the receiving side).

`timescale 1ns/100ps

module axi_ad9361_dev_if (

  // physical interface (receive)

  rx_clk_in_p,
  rx_clk_in_n,
  rx_frame_in_p,
  rx_frame_in_n,
  rx_data_in_p,
  rx_data_in_n,

  // physical interface (transmit)

  tx_clk_out_p,
  tx_clk_out_n,
  tx_frame_out_p,
  tx_frame_out_n,
  tx_data_out_p,
  tx_data_out_n,

  // clock (common to both receive and transmit)

  rst,
  clk,
  l_clk,

  // receive data path interface

  adc_valid,
  adc_data,
  adc_status,
  adc_r1_mode,
  adc_ddr_edgesel,

  // transmit data path interface

  dac_valid,
  dac_data,
  dac_r1_mode,

  // delay control signals

  delay_clk,
  delay_rst,
  delay_sel,
  delay_rwn,
  delay_addr,
  delay_wdata,
  delay_rdata,
  delay_ack_t,
  delay_locked,

  // chipscope signals

  dev_dbg_data,
  dev_l_dbg_data);

  // this parameter controls the buffer type based on the target device.

  parameter   PCORE_DEVICE_TYPE = 0;
  parameter   PCORE_IODELAY_GROUP = "dev_if_delay_group";
  localparam  PCORE_7SERIES = 0;
  localparam  PCORE_VIRTEX6 = 1;

  // physical interface (receive)

  input           rx_clk_in_p;
  input           rx_clk_in_n;
  input           rx_frame_in_p;
  input           rx_frame_in_n;
  input   [ 5:0]  rx_data_in_p;
  input   [ 5:0]  rx_data_in_n;

  // physical interface (transmit)

  output          tx_clk_out_p;
  output          tx_clk_out_n;
  output          tx_frame_out_p;
  output          tx_frame_out_n;
  output  [ 5:0]  tx_data_out_p;
  output  [ 5:0]  tx_data_out_n;

  // clock (common to both receive and transmit)

  input           rst;
  input           clk;
  output          l_clk;

  // receive data path interface

  output          adc_valid;
  output  [47:0]  adc_data;
  output          adc_status;
  input           adc_r1_mode;
  input           adc_ddr_edgesel;

  // transmit data path interface

  input           dac_valid;
  input   [47:0]  dac_data;
  input           dac_r1_mode;

  // delay control signals

  input           delay_clk;
  input           delay_rst;
  input           delay_sel;
  input           delay_rwn;
  input   [ 7:0]  delay_addr;
  input   [ 4:0]  delay_wdata;
  output  [ 4:0]  delay_rdata;
  output          delay_ack_t;
  output          delay_locked;

  // chipscope signals

  output [111:0]  dev_dbg_data;
  output [ 61:0]  dev_l_dbg_data;

  // internal registers

  reg     [ 5:0]  rx_data_p = 0;
  reg             rx_frame_p = 0;
  reg     [ 1:0]  rx_ccnt = 0;
  reg             rx_calign = 0;
  reg             rx_align = 0;
  reg     [11:0]  rx_data = 'd0;
  reg     [ 1:0]  rx_frame = 'd0;
  reg     [11:0]  rx_data_d = 'd0;
  reg     [ 1:0]  rx_frame_d = 'd0;
  reg             rx_error_r1 = 'd0;
  reg             rx_valid_r1 = 'd0;
  reg     [23:0]  rx_data_r1 = 'd0;
  reg             rx_error_r2 = 'd0;
  reg             rx_valid_r2 = 'd0;
  reg     [47:0]  rx_data_r2 = 'd0;
  reg             adc_p_valid = 'd0;
  reg     [47:0]  adc_p_data = 'd0;
  reg             adc_p_status = 'd0;
  reg             adc_n_valid = 'd0;
  reg     [47:0]  adc_n_data = 'd0;
  reg             adc_n_status = 'd0;
  reg             adc_valid_int = 'd0;
  reg     [47:0]  adc_data_int = 'd0;
  reg             adc_status_int = 'd0;
  reg             adc_valid = 'd0;
  reg     [47:0]  adc_data = 'd0;
  reg             adc_status = 'd0;
  reg     [ 2:0]  tx_data_cnt = 'd0;
  reg     [47:0]  tx_data = 'd0;
  reg             tx_frame = 'd0;
  reg     [ 5:0]  tx_data_p = 'd0;
  reg     [ 5:0]  tx_data_n = 'd0;
  reg             tx_n_frame = 'd0;
  reg     [ 5:0]  tx_n_data_p = 'd0;
  reg     [ 5:0]  tx_n_data_n = 'd0;
  reg             tx_p_frame = 'd0;
  reg     [ 5:0]  tx_p_data_p = 'd0;
  reg     [ 5:0]  tx_p_data_n = 'd0;
  reg     [ 6:0]  delay_ld = 'd0;
  reg     [ 4:0]  delay_rdata = 'd0;
  reg             delay_ack_t = 'd0;

  // internal signals

  wire            rx_align_s;
  wire    [ 3:0]  rx_frame_s;
  wire    [ 3:0]  tx_data_sel_s;
  wire    [ 4:0]  delay_rdata_s[6:0];
  wire    [ 5:0]  rx_data_p_s;
  wire    [ 5:0]  rx_data_n_s;
  wire            rx_frame_p_s;
  wire            rx_frame_n_s;

  genvar          l_inst;

  // device debug signals

  assign dev_dbg_data[  5:  0] = tx_data_n;
  assign dev_dbg_data[ 11:  6] = tx_data_p;
  assign dev_dbg_data[ 23: 12] = dac_data[11: 0];
  assign dev_dbg_data[ 35: 24] = dac_data[23:12];
  assign dev_dbg_data[ 47: 36] = dac_data[35:24];
  assign dev_dbg_data[ 59: 48] = dac_data[47:36];
  assign dev_dbg_data[ 71: 60] = adc_data[11: 0];
  assign dev_dbg_data[ 83: 72] = adc_data[23:12];
  assign dev_dbg_data[ 95: 84] = adc_data[35:24];
  assign dev_dbg_data[107: 96] = adc_data[47:36];
  assign dev_dbg_data[108:108] = tx_frame;
  assign dev_dbg_data[109:109] = dac_valid;
  assign dev_dbg_data[110:110] = adc_status;
  assign dev_dbg_data[111:111] = adc_valid;

  assign dev_l_dbg_data[  5:  0] = tx_p_data_n;
  assign dev_l_dbg_data[ 11:  6] = tx_p_data_p;
  assign dev_l_dbg_data[ 23: 12] = adc_p_data[11: 0];
  assign dev_l_dbg_data[ 35: 24] = adc_p_data[23:12];
  assign dev_l_dbg_data[ 47: 36] = adc_p_data[35:24];
  assign dev_l_dbg_data[ 59: 48] = adc_p_data[47:36];
  assign dev_l_dbg_data[ 60: 60] = tx_p_frame;
  assign dev_l_dbg_data[ 61: 61] = adc_p_valid;

  // receive data path interface

  assign rx_align_s = rx_frame_n_s ^ rx_frame_p_s;

  always @(posedge l_clk) begin
    rx_data_p <= rx_data_p_s;
    rx_frame_p <= rx_frame_p_s;
    rx_ccnt <= rx_ccnt + 1'b1;
    if (rx_ccnt == 2'd0) begin
      rx_calign <= rx_align;
      rx_align <= rx_align_s;
    end else begin
      rx_calign <= rx_calign;
      rx_align <= rx_align | rx_align_s;
    end
  end

  assign rx_frame_s = {rx_frame_d, rx_frame};

  always @(posedge l_clk) begin
    if (rx_calign == 1'b1) begin
      rx_data <= {rx_data_p, rx_data_n_s};
      rx_frame <= {rx_frame_p, rx_frame_n_s};
    end else begin
      rx_data <= {rx_data_n_s, rx_data_p_s};
      rx_frame <= {rx_frame_n_s, rx_frame_p_s};
    end
    rx_data_d <= rx_data;
    rx_frame_d <= rx_frame;
  end

  // receive data path for single rf, frame is expected to qualify i/q msb only

  always @(posedge l_clk) begin
    rx_error_r1 <= ((rx_frame_s == 4'b1100) || (rx_frame_s == 4'b0011)) ? 1'b0 : 1'b1;
    rx_valid_r1 <= (rx_frame_s == 4'b1100) ? 1'b1 : 1'b0;
    if (rx_frame_s == 4'b1100) begin
      rx_data_r1[11: 0] <= {rx_data_d[11:6], rx_data[11:6]};
      rx_data_r1[23:12] <= {rx_data_d[ 5:0], rx_data[ 5:0]};
    end
  end

  // receive data path for dual rf, frame is expected to qualify i/q msb and lsb for rf-1 only

  always @(posedge l_clk) begin
    rx_error_r2 <= ((rx_frame_s == 4'b1111) || (rx_frame_s == 4'b1100) ||
      (rx_frame_s == 4'b0000) || (rx_frame_s == 4'b0011)) ? 1'b0 : 1'b1;
    rx_valid_r2 <= (rx_frame_s == 4'b0000) ? 1'b1 : 1'b0;
    if (rx_frame_s == 4'b1111) begin
      rx_data_r2[11: 0] <= {rx_data_d[11:6], rx_data[11:6]};
      rx_data_r2[23:12] <= {rx_data_d[ 5:0], rx_data[ 5:0]};
    end
    if (rx_frame_s == 4'b0000) begin
      rx_data_r2[35:24] <= {rx_data_d[11:6], rx_data[11:6]};
      rx_data_r2[47:36] <= {rx_data_d[ 5:0], rx_data[ 5:0]};
    end
  end

  // receive data path mux

  always @(posedge l_clk) begin
    if (adc_r1_mode == 1'b1) begin
      adc_p_valid <= rx_valid_r1;
      adc_p_data <= {24'd0, rx_data_r1};
      adc_p_status <= ~rx_error_r1;
    end else begin
      adc_p_valid <= rx_valid_r2;
      adc_p_data <= rx_data_r2;
      adc_p_status <= ~rx_error_r2;
    end
  end

  // transfer to a synchronous common clock

  always @(negedge l_clk) begin
    adc_n_valid <= adc_p_valid;
    adc_n_data <= adc_p_data;
    adc_n_status <= adc_p_status;
  end

  always @(posedge clk) begin
    adc_valid_int <= adc_n_valid;
    adc_data_int <= adc_n_data;
    adc_status_int <= adc_n_status;
    adc_valid <= adc_valid_int;
    if (adc_valid_int == 1'b1) begin
      adc_data <= adc_data_int;
    end
    adc_status <= adc_status_int;
  end

  // transmit data path mux (reverse of what receive does above)
  // the count simply selets the data muxing on the ddr outputs

  assign tx_data_sel_s = {tx_data_cnt[2], dac_r1_mode, tx_data_cnt[1:0]};

  always @(posedge clk) begin
    if (dac_valid == 1'b1) begin
      tx_data_cnt <= 3'b100;
    end else if (tx_data_cnt[2] == 1'b1) begin
      tx_data_cnt <= tx_data_cnt + 1'b1;
    end
    if (dac_valid == 1'b1) begin
      tx_data <= dac_data;
    end
    case (tx_data_sel_s)
      4'b1111: begin
        tx_frame <= 1'b0;
        tx_data_p <= tx_data[ 5: 0];
        tx_data_n <= tx_data[17:12];
      end
      4'b1110: begin
        tx_frame <= 1'b1;
        tx_data_p <= tx_data[11: 6];
        tx_data_n <= tx_data[23:18];
      end
      4'b1101: begin
        tx_frame <= 1'b0;
        tx_data_p <= tx_data[ 5: 0];
        tx_data_n <= tx_data[17:12];
      end
      4'b1100: begin
        tx_frame <= 1'b1;
        tx_data_p <= tx_data[11: 6];
        tx_data_n <= tx_data[23:18];
      end
      4'b1011: begin
        tx_frame <= 1'b0;
        tx_data_p <= tx_data[29:24];
        tx_data_n <= tx_data[41:36];
      end
      4'b1010: begin
        tx_frame <= 1'b0;
        tx_data_p <= tx_data[35:30];
        tx_data_n <= tx_data[47:42];
      end
      4'b1001: begin
        tx_frame <= 1'b1;
        tx_data_p <= tx_data[ 5: 0];
        tx_data_n <= tx_data[17:12];
      end
      4'b1000: begin
        tx_frame <= 1'b1;
        tx_data_p <= tx_data[11: 6];
        tx_data_n <= tx_data[23:18];
      end
      default: begin
        tx_frame <= 1'b0;
        tx_data_p <= 6'd0;
        tx_data_n <= 6'd0;
      end
    endcase
  end

  // transfer data from a synchronous clock (skew less than 2ns)

  always @(negedge clk) begin
    tx_n_frame <= tx_frame;
    tx_n_data_p <= tx_data_p;
    tx_n_data_n <= tx_data_n;
  end

  always @(posedge l_clk) begin
    tx_p_frame <= tx_n_frame;
    tx_p_data_p <= tx_n_data_p;
    tx_p_data_n <= tx_n_data_n;
  end

  // delay write interface, each delay element can be individually
  // addressed, and a delay value can be directly loaded (no inc/dec stuff)

  always @(posedge delay_clk) begin
    if ((delay_sel == 1'b1) && (delay_rwn == 1'b0)) begin
      case (delay_addr)
        8'h06: delay_ld <= 7'h40;
        8'h05: delay_ld <= 7'h20;
        8'h04: delay_ld <= 7'h10;
        8'h03: delay_ld <= 7'h08;
        8'h02: delay_ld <= 7'h04;
        8'h01: delay_ld <= 7'h02;
        8'h00: delay_ld <= 7'h01;
        default: delay_ld <= 7'h00;
      endcase
    end else begin
      delay_ld <= 7'h00;
    end
  end

  // delay read interface, a delay ack toggle is used to transfer data to the
  // processor side- delay locked is independently transferred

  always @(posedge delay_clk) begin
    case (delay_addr)
      8'h06: delay_rdata <= delay_rdata_s[6];
      8'h05: delay_rdata <= delay_rdata_s[5];
      8'h04: delay_rdata <= delay_rdata_s[4];
      8'h03: delay_rdata <= delay_rdata_s[3];
      8'h02: delay_rdata <= delay_rdata_s[2];
      8'h01: delay_rdata <= delay_rdata_s[1];
      8'h00: delay_rdata <= delay_rdata_s[0];
      default: delay_rdata <= 5'd0;
    endcase
    if (delay_sel == 1'b1) begin
      delay_ack_t <= ~delay_ack_t;
    end
  end

  // receive data interface, ibuf -> idelay -> iddr

  generate
  for (l_inst = 0; l_inst <= 5; l_inst = l_inst + 1) begin: g_rx_data
  ad_lvds_in #(
    .BUFTYPE (PCORE_DEVICE_TYPE),
    .IODELAY_CTRL (0),
    .IODELAY_GROUP (PCORE_IODELAY_GROUP))
  i_rx_data (
    .rx_clk (l_clk),
    .rx_data_in_p (rx_data_in_p[l_inst]),
    .rx_data_in_n (rx_data_in_n[l_inst]),
    .rx_data_p (rx_data_p_s[l_inst]),
    .rx_data_n (rx_data_n_s[l_inst]),
    .delay_clk (delay_clk),
    .delay_rst (delay_rst),
    .delay_ld (delay_ld[l_inst]),
    .delay_wdata (delay_wdata),
    .delay_rdata (delay_rdata_s[l_inst]),
    .delay_locked ());
  end
  endgenerate

  // receive frame interface, ibuf -> idelay -> iddr

  ad_lvds_in #(
    .BUFTYPE (PCORE_DEVICE_TYPE),
    .IODELAY_CTRL (1),
    .IODELAY_GROUP (PCORE_IODELAY_GROUP))
  i_rx_frame (
    .rx_clk (l_clk),
    .rx_data_in_p (rx_frame_in_p),
    .rx_data_in_n (rx_frame_in_n),
    .rx_data_p (rx_frame_p_s),
    .rx_data_n (rx_frame_n_s),
    .delay_clk (delay_clk),
    .delay_rst (delay_rst),
    .delay_ld (delay_ld[6]),
    .delay_wdata (delay_wdata),
    .delay_rdata (delay_rdata_s[6]),
    .delay_locked (delay_locked));

  // transmit data interface, oddr -> obuf

  generate
  for (l_inst = 0; l_inst <= 5; l_inst = l_inst + 1) begin: g_tx_data
  ad_lvds_out #(
    .BUFTYPE (PCORE_DEVICE_TYPE))
  i_tx_data (
    .tx_clk (l_clk),
    .tx_data_p (tx_p_data_p[l_inst]),
    .tx_data_n (tx_p_data_n[l_inst]),
    .tx_data_out_p (tx_data_out_p[l_inst]),
    .tx_data_out_n (tx_data_out_n[l_inst]));
  end
  endgenerate

  // transmit frame interface, oddr -> obuf

  ad_lvds_out #(
    .BUFTYPE (PCORE_DEVICE_TYPE))
  i_tx_frame (
    .tx_clk (l_clk),
    .tx_data_p (tx_p_frame),
    .tx_data_n (tx_p_frame),
    .tx_data_out_p (tx_frame_out_p),
    .tx_data_out_n (tx_frame_out_n));

  // transmit clock interface, oddr -> obuf

  ad_lvds_out #(
    .BUFTYPE (PCORE_DEVICE_TYPE))
  i_tx_clk (
    .tx_clk (l_clk),
    .tx_data_p (1'b0),
    .tx_data_n (1'b1),
    .tx_data_out_p (tx_clk_out_p),
    .tx_data_out_n (tx_clk_out_n));

  // device clock interface (receive clock)

  ad_lvds_clk #(
    .BUFTYPE (PCORE_DEVICE_TYPE))
  i_clk (
    .clk_in_p (rx_clk_in_p),
    .clk_in_n (rx_clk_in_n),
    .clk (l_clk));

endmodule

// ***************************************************************************
// ***************************************************************************