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`define DSP_CORE_RX_BASE 160
module dsp_core_rx
(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;
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({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(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(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
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