| Line 8... |
Line 8... |
parameter CIC_M = 1, ///< delay in comb
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parameter CIC_M = 1, ///< delay in comb
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parameter SMALL_FOOTPRINT = 1 ///< reduced registers usage, f_clk / (f_samp/CIC_R) > CIC_N required
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parameter SMALL_FOOTPRINT = 1 ///< reduced registers usage, f_clk / (f_samp/CIC_R) > CIC_N required
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)
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)
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/*********************************************************************************************/
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/*********************************************************************************************/
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(
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(
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input clk,
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input clk, ///< input clock
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input reset_n,
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input reset_n, ///< input reset
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input clear,
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input clear, ///< input clear integrator, set accumulator to 0
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input wire signed [INP_DW-1:0] inp_samp_data,
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input wire signed [INP_DW-1:0] inp_samp_data, ///< input data
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input inp_samp_str,
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input inp_samp_str, ///< input data ready strobe
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output wire signed [OUT_DW-1:0] out_samp_data,
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output wire signed [OUT_DW-1:0] out_samp_data, ///< output data
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output out_samp_str
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output out_samp_str ///< output data ready strobe
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);
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);
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/*********************************************************************************************/
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/*********************************************************************************************/
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`include "cic_functions.vh"
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`include "cic_functions.vh"
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/*********************************************************************************************/
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/*********************************************************************************************/
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localparam B_max = clog2_l((CIC_R * CIC_M) ** CIC_N) + INP_DW - 1;
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localparam B_max = clog2_l((CIC_R * CIC_M) ** CIC_N) + INP_DW - 1;
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/*********************************************************************************************/
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/*********************************************************************************************/
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|
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genvar i;
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genvar i;
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generate
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generate
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for (i = 0; i < CIC_N; i = i + 1) begin : int_stage
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for (i = 0; i < CIC_N; i = i + 1) begin : int_stage
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localparam B_jm1 = B_calc(i , CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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localparam B_jm1 = B_calc(i , CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW); ///< the number of bits to prune in previous stage
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localparam B_j = B_calc(i + 1, CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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localparam B_j = B_calc(i + 1, CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW); ///< the number of bits to prune in current stage
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localparam F_sq_j = 0;
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localparam idw_cur = B_max - B_jm1 + 1; ///< data width on the input
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localparam idw_cur = B_max - B_jm1 + 1;
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localparam odw_cur = B_max - B_j + 1; ///< data width on the output
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localparam odw_cur = B_max - B_j + 1;
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wire signed [idw_cur - 1 : 0] int_in; ///< input data bus
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localparam B_dw_prev = (i != 0) ? B_max - B_jm1 + 1 : 0;
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if ( i == 0 ) assign int_in = inp_samp_data; ///< if it is the first stage, then takes data from input of CIC filter
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wire signed [idw_cur - 1 : 0] int_in;
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else assign int_in = int_stage[i - 1].int_out; ///< otherwise, takes data from the previous stage of the filter
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if ( i == 0 ) assign int_in = inp_samp_data;
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else assign int_in = int_stage[i - 1].int_out;
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wire signed [idw_cur - 1 : 0] int_inst_out;
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wire signed [odw_cur - 1 : 0] int_out;
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wire signed [odw_cur - 1 : 0] int_out;
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assign int_out = int_inst_out[idw_cur - 1 -: odw_cur];
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integrator #(
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integrator #(
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idw_cur,
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idw_cur,
|
idw_cur
|
odw_cur
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)
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)
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int_inst(
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int_inst(
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.clk (clk),
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.clk (clk),
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.reset_n (reset_n),
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.reset_n (reset_n),
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.clear (clear) ,
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.clear (clear) ,
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.inp_samp_data (int_in),
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.inp_samp_data (int_in),
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.inp_samp_str (inp_samp_str),
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.inp_samp_str (inp_samp_str),
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.out_samp_data (int_inst_out)
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.out_samp_data (int_out)
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);
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);
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initial begin
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initial begin
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//$display("i:%d integ idw=%2d odw=%2d B(%2d, %3d, %2d, %2d, %2d, %2d)=%2d, Bj-1=%2d, F_sq=%8d", i, idw_cur, odw_cur, i + 1, CIC_R, CIC_M, CIC_N, INP_DW, OUT_DW, B_j, B_jm1, F_sq_j);
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//$display("i:%d integ idw=%2d odw=%2d B(%2d, %3d, %2d, %2d, %2d, %2d)=%2d, Bj-1=%2d, F_sq=%8d", i, idw_cur, odw_cur, i + 1, CIC_R, CIC_M, CIC_N, INP_DW, OUT_DW, B_j, B_jm1, F_sq_j);
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$display("i:%d integ idw=%d ", i, idw_cur);
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$display("i:%d integ idw=%d ", i, idw_cur);
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end
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end
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end
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end
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endgenerate
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endgenerate
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/*********************************************************************************************/
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/*********************************************************************************************/
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localparam B_m = B_calc(CIC_N, CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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/// downsampler takes data from m-th stage
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localparam ds_dw = B_max - B_m + 1;
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localparam B_m = B_calc(CIC_N, CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW); ///< bits to prune on the m-th stage
|
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localparam ds_dw = B_max - B_m + 1; ///< data width of the downsampler
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wire signed [ds_dw - 1 : 0] ds_out_samp_data;
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wire signed [ds_dw - 1 : 0] ds_out_samp_data;
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wire ds_out_samp_str;
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wire ds_out_samp_str;
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/*********************************************************************************************/
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/*********************************************************************************************/
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initial begin
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initial begin
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//$display("i downsamp dw %d , int_stage[%2d].dw_out = %2d", ds_dw, CIC_N - 1, int_stage[CIC_N - 1].odw_cur);
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//$display("i downsamp dw %d , int_stage[%2d].dw_out = %2d", ds_dw, CIC_N - 1, int_stage[CIC_N - 1].odw_cur);
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| Line 85... |
Line 81... |
genvar j;
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genvar j;
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wire comb_chain_out_str;
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wire comb_chain_out_str;
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reg [CIC_N : 0] comb_inp_str_d;
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reg [CIC_N : 0] comb_inp_str_d;
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generate
|
generate
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wire summ_rdy_str;
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wire summ_rdy_str;
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if (SMALL_FOOTPRINT != 0) begin
|
if (SMALL_FOOTPRINT != 0) begin ///< generate comb for small footprint
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always @(negedge reset_n or posedge clk)
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always @(negedge reset_n or posedge clk) ///< shift register for strobe from datasampler, used to latch data from comb at N'th clock after downsamplers strobe
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if (~reset_n) comb_inp_str_d <= '0;
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if (~reset_n) comb_inp_str_d <= '0;
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else if (clear) comb_inp_str_d <= '0;
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else if (clear) comb_inp_str_d <= '0;
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else comb_inp_str_d <= {comb_inp_str_d[CIC_N - 1 : 0], ds_out_samp_str};
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else comb_inp_str_d <= {comb_inp_str_d[CIC_N - 1 : 0], ds_out_samp_str};
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end
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end
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| Line 99... |
Line 95... |
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|
|
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for (j = 0; j < CIC_N; j = j + 1) begin : comb_stage
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for (j = 0; j < CIC_N; j = j + 1) begin : comb_stage
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localparam B_m_j_m1 = B_calc(CIC_N + j , CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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localparam B_m_j_m1 = B_calc(CIC_N + j , CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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localparam B_m_j = B_calc(CIC_N + j + 1, CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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localparam B_m_j = B_calc(CIC_N + j + 1, CIC_N, CIC_R, CIC_M, INP_DW, OUT_DW);
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localparam F_sq_j = 1;
|
|
localparam idw_cur = B_max - B_m_j_m1 + 1;
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localparam idw_cur = B_max - B_m_j_m1 + 1;
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localparam odw_cur = B_max - B_m_j + 1;
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localparam odw_cur = B_max - B_m_j + 1;
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wire signed [idw_cur - 1 : 0] comb_in;
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wire signed [idw_cur - 1 : 0] comb_in;
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wire signed [idw_cur - 1 : 0] comb_inst_out;
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wire signed [idw_cur - 1 : 0] comb_inst_out;
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wire signed [odw_cur - 1 : 0] comb_out;
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wire signed [odw_cur - 1 : 0] comb_out;
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| Line 127... |
Line 122... |
.samp_out_data (comb_inst_out)
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.samp_out_data (comb_inst_out)
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);
|
);
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if (SMALL_FOOTPRINT == 0) assign comb_chain_out_str = comb_stage[CIC_N - 1].comb_dv;
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if (SMALL_FOOTPRINT == 0) assign comb_chain_out_str = comb_stage[CIC_N - 1].comb_dv;
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else assign comb_chain_out_str = comb_inp_str_d[CIC_N - 1];
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else assign comb_chain_out_str = comb_inp_str_d[CIC_N - 1];
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initial begin
|
initial begin
|
//$display("i:%d comb idw=%2d odw=%2d B(%2d, %3d, %2d, %2d, %2d, %2d)=%2d, ln(F_sq)=%4d, F_sq=%8d", j, idw_cur, odw_cur, CIC_N + j + 1, CIC_R, CIC_M, CIC_N, INP_DW, OUT_DW, B_m_j, $ln(F_sq_j), F_sq_j);
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//$display("i:%d comb idw=%2d odw=%2d B(%2d, %3d, %2d, %2d, %2d, %2d)=%2d", j, idw_cur, odw_cur, CIC_N + j + 1, CIC_R, CIC_M, CIC_N, INP_DW, OUT_DW, B_m_j);
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//if (j != 0) $display("odw_prev=%2d, comb_stage[j - 1].odw_cur=%2d", odw_prev, comb_stage[j - 1].odw_cur);
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//if (j != 0) $display("odw_prev=%2d, comb_stage[j - 1].odw_cur=%2d", odw_prev, comb_stage[j - 1].odw_cur);
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$display("i:%d comb idw=%d", j, idw_cur);
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$display("i:%d comb idw=%d", j, idw_cur);
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end
|
end
|
end
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end
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endgenerate
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endgenerate
|
