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authorJosh Blum <josh@joshknows.com>2012-02-10 12:13:51 -0800
committerJosh Blum <josh@joshknows.com>2012-02-10 12:13:51 -0800
commit6d45600ada785cb50a01a17dcddf561d12501d22 (patch)
treec223f87aebf64f305b4bfe83e0ce799d01dad59a /usrp2/sdr_lib/ddc_chain.v
parent34db74740704ce2de2a71447b3d202e9c4be800b (diff)
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dsp rework: pass enables into glue, update power trig, parameterize, fix module inc
DSP enables now pass through the glue and custom modules so it can be user-controlled. Updated power trigger to current spec, and added comments Pass width from dsp into glue, and use width to parameterize wires Fix custom module includes so they will build
Diffstat (limited to 'usrp2/sdr_lib/ddc_chain.v')
-rw-r--r--usrp2/sdr_lib/ddc_chain.v94
1 files changed, 53 insertions, 41 deletions
diff --git a/usrp2/sdr_lib/ddc_chain.v b/usrp2/sdr_lib/ddc_chain.v
index 800bb5b13..c32c9f491 100644
--- a/usrp2/sdr_lib/ddc_chain.v
+++ b/usrp2/sdr_lib/ddc_chain.v
@@ -18,14 +18,18 @@
//! The USRP digital down-conversion chain
module ddc_chain
- #(parameter BASE = 0, parameter DSPNO = 0)
+ #(
+ 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 [23:0] rx_fe_i,
- input [23:0] rx_fe_q,
+ input [WIDTH-1:0] rx_fe_i,
+ input [WIDTH-1:0] rx_fe_q,
// To RX control
output [31:0] sample,
@@ -34,21 +38,25 @@ module ddc_chain
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 [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 [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 [23:0] rx_fe_i_mux, rx_fe_q_mux;
+ reg [WIDTH-1:0] rx_fe_i_mux, rx_fe_q_mux;
wire realmode;
wire swap_iq;
@@ -74,103 +82,107 @@ module ddc_chain
if(swap_iq)
begin
rx_fe_i_mux <= rx_fe_q;
- rx_fe_q_mux <= realmode ? 24'd0 : rx_fe_i;
+ rx_fe_q_mux <= realmode ? 0 : rx_fe_i;
end
else
begin
rx_fe_i_mux <= rx_fe_i;
- rx_fe_q_mux <= realmode ? 24'd0 : rx_fe_q;
+ rx_fe_q_mux <= realmode ? 0 : rx_fe_q;
end
// NCO
always @(posedge clk)
if(rst)
phase <= 0;
- else if(~run)
+ else if(~ddc_enb)
phase <= 0;
else
phase <= phase + phase_inc;
- wire [23:0] to_cordic_i, to_cordic_q;
+ //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(25))
- cordic(.clock(clk), .reset(rst), .enable(run),
- .xi({to_cordic_i[23],to_cordic_i}),. yi({to_cordic_q[23],to_cordic_q}), .zi(phase[31:8]),
+ 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(25), .bits_out(24)) clip_i
+ 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(25), .bits_out(24)) clip_q
+ 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(run),.rate(cic_decim_rate),
+ 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(24))
- decim_i (.clock(clk),.reset(rst),.enable(run),
+ 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(24))
- decim_q (.clock(clk),.reset(rst),.enable(run),
+ 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(24)) small_hb_i
- (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
+ 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(24)) small_hb_q
- (.clk(clk),.rst(rst),.bypass(~enable_hb1),.run(run),
+ 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(24)) hb_i
- (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
+ 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(24)) hb_q
- (.clk(clk),.rst(rst),.bypass(~enable_hb2),.run(run),.cpi(cpi_hb),
+ 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[23:6]), .B(scale_factor), .C(clk), .CE(strobe_hb2), .R(rst) );
+ (.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[23:6]), .B(scale_factor), .C(clk), .CE(strobe_hb2), .R(rst) );
+ (.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 [23:0] prod_reg_i, prod_reg_q;
+ 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[33:10];
- prod_reg_q <= prod_q[33:10];
+ 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(24),.WIDTH_OUT(16)) round_i
+ 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(24),.WIDTH_OUT(16)) round_q
+ 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)) custom(
+ 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_cordic_i), .ddc_in_q(to_cordic_q),
- .ddc_out_sample(ddc_chain_out), .ddc_out_strobe(ddc_chain_stb),
+ .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};