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authorBen Hilburn <ben.hilburn@ettus.com>2014-02-14 12:05:07 -0800
committerBen Hilburn <ben.hilburn@ettus.com>2014-02-14 12:05:07 -0800
commitff1546f8137f7f92bb250f685561b0c34cc0e053 (patch)
tree7fa6fd05c8828df256a1b20e2935bd3ba9899e2c /fpga/usrp3/lib/dsp/tx_frontend.v
parent4f691d88123784c2b405816925f1a1aef69d18c1 (diff)
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Pushing the bulk of UHD-3.7.0 code.
Diffstat (limited to 'fpga/usrp3/lib/dsp/tx_frontend.v')
-rw-r--r--fpga/usrp3/lib/dsp/tx_frontend.v97
1 files changed, 97 insertions, 0 deletions
diff --git a/fpga/usrp3/lib/dsp/tx_frontend.v b/fpga/usrp3/lib/dsp/tx_frontend.v
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+
+module tx_frontend
+ #(parameter BASE=0,
+ parameter WIDTH_OUT=16,
+ parameter IQCOMP_EN=1)
+ (input clk, input rst,
+ input set_stb, input [7:0] set_addr, input [31:0] set_data,
+ input [23:0] tx_i, input [23:0] tx_q, input run,
+ output reg [WIDTH_OUT-1:0] dac_a, output reg [WIDTH_OUT-1:0] dac_b
+ );
+
+ // IQ balance --> DC offset --> rounding --> mux
+
+ wire [23:0] i_dco, q_dco, i_ofs, q_ofs;
+ wire [WIDTH_OUT-1:0] i_final, q_final;
+ wire [7:0] mux_ctrl;
+ wire [35:0] corr_i, corr_q;
+ wire [23:0] i_bal, q_bal;
+ wire [17:0] mag_corr, phase_corr;
+
+ setting_reg #(.my_addr(BASE+0), .width(24)) sr_0
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(i_dco),.changed());
+
+ setting_reg #(.my_addr(BASE+1), .width(24)) sr_1
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(q_dco),.changed());
+
+ setting_reg #(.my_addr(BASE+2),.width(18)) sr_2
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(mag_corr),.changed());
+
+ setting_reg #(.my_addr(BASE+3),.width(18)) sr_3
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(phase_corr),.changed());
+
+ setting_reg #(.my_addr(BASE+4), .width(8)) sr_4
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(mux_ctrl),.changed());
+
+ generate
+ if(IQCOMP_EN==1)
+ begin
+ // IQ Balance
+ MULT18X18S mult_mag_corr
+ (.P(corr_i), .A(tx_i[23:6]), .B(mag_corr), .C(clk), .CE(1), .R(rst) );
+
+ MULT18X18S mult_phase_corr
+ (.P(corr_q), .A(tx_i[23:6]), .B(phase_corr), .C(clk), .CE(1), .R(rst) );
+
+ add2_and_clip_reg #(.WIDTH(24)) add_clip_i
+ (.clk(clk), .rst(rst),
+ .in1(tx_i), .in2(corr_i[35:12]), .strobe_in(1'b1),
+ .sum(i_bal), .strobe_out());
+
+ add2_and_clip_reg #(.WIDTH(24)) add_clip_q
+ (.clk(clk), .rst(rst),
+ .in1(tx_q), .in2(corr_q[35:12]), .strobe_in(1'b1),
+ .sum(q_bal), .strobe_out());
+ end // if (IQCOMP_EN==1)
+ else
+ begin
+ assign i_bal = tx_i;
+ assign q_bal = tx_q;
+ end // else: !if(IQCOMP_EN==1)
+ endgenerate
+
+ // DC Offset
+ add2_and_clip_reg #(.WIDTH(24)) add_dco_i
+ (.clk(clk), .rst(rst), .in1(i_dco), .in2(i_bal), .strobe_in(1'b1), .sum(i_ofs), .strobe_out());
+
+ add2_and_clip_reg #(.WIDTH(24)) add_dco_q
+ (.clk(clk), .rst(rst), .in1(q_dco), .in2(q_bal), .strobe_in(1'b1), .sum(q_ofs), .strobe_out());
+
+ // Rounding
+ round_sd #(.WIDTH_IN(24),.WIDTH_OUT(WIDTH_OUT)) round_i
+ (.clk(clk), .reset(rst), .in(i_ofs),.strobe_in(1'b1), .out(i_final), .strobe_out());
+
+ round_sd #(.WIDTH_IN(24),.WIDTH_OUT(WIDTH_OUT)) round_q
+ (.clk(clk), .reset(rst), .in(q_ofs),.strobe_in(1'b1), .out(q_final), .strobe_out());
+
+ // Mux
+ always @(posedge clk)
+ case(mux_ctrl[3:0])
+ 0 : dac_a <= i_final;
+ 1 : dac_a <= q_final;
+ default : dac_a <= 0;
+ endcase // case (mux_ctrl[3:0])
+
+ always @(posedge clk)
+ case(mux_ctrl[7:4])
+ 0 : dac_b <= i_final;
+ 1 : dac_b <= q_final;
+ default : dac_b <= 0;
+ endcase // case (mux_ctrl[7:4])
+
+endmodule // tx_frontend