/********************************************** _ _ Cook Darwin __

_ descript: author : Cook.Darwin Version: VERB.0.0 : 2017/2/28

add custom signals ,sync to last

creaded: 2017/2/27 madified: ***********************************************/ `timescale 1ns/1ps // (* axi_stream = “true” *) module axi_stream_packet_fifo_verb #(

parameter DEPTH   = 2,   //2-4
parameter CSIZE   = 1

)(

input [CSIZE-1:0]          in_cdata,
output[CSIZE-1:0]          out_cdata,
(* up_stream = "true" *)
axi_stream_inf.slaver      axis_in,
(* down_stream = "true" *)
axi_stream_inf.master      axis_out

);

//—>> NATIVE FIFO IP <<—————————— logic data_fifo_full; logic data_fifo_empty;

xilinx_fifo_verb #( //xilinx_fifo #(

.DSIZE      (axis_in.DSIZE  )

)stream_packet_fifo_inst ( /* input */ .wr_clk (axis_in.aclk ), /* input */ .wr_rst (!axis_in.aresetn ), /* input */ .rd_clk (axis_out.aclk ), /* input */ .rd_rst (!axis_out.aresetn ), /* input [255:0] */ .din (axis_in.axis_tdata ), /* input */ .wr_en ((axis_in.axis_tvalid && axis_in.axis_tready) ), /* input */ .rd_en ((axis_out.axis_tvalid && axis_out.axis_tready) ), /* output [255:0] */ .dout (axis_out.axis_tdata ), /* output */ .full (data_fifo_full ), /* output */ .empty (data_fifo_empty ) ); //—<< NATIVE FIFO IP >>——————————

//—>> PACKET <<————————————– logic packet_fifo_full; logic packet_fifo_empty; logic [15:0] w_bytes_total; logic [15:0] r_bytes_total; logic w_total_eq_1; logic r_total_eq_1;

assign w_total_eq_1 = w_bytes_total=='0;

localparam IDEPTH = (DEPTH<4)? 4 : DEPTH;

independent_clock_fifo #(

.DEPTH      (IDEPTH     ),
.DSIZE      (16+1+CSIZE      )

)common_independent_clock_fifo_inst( /* input */ .wr_clk (axis_in.aclk ), /* input */ .wr_rst_n (axis_in.aresetn ), /* input */ .rd_clk (axis_out.aclk ), /* input */ .rd_rst_n (axis_out.aresetn ), /* input [DSIZE-1:0] */ .wdata ({w_total_eq_1,w_bytes_total,in_cdata} ), /* input */ .wr_en ((axis_in.axis_tvalid && axis_in.axis_tlast && axis_in.axis_tready) ), /* output logic */ .rdata ({r_total_eq_1,r_bytes_total,out_cdata} ), /* input */ .rd_en ((axis_out.axis_tvalid && axis_out.axis_tlast && axis_out.axis_tready) ), /* output logic */ .empty (packet_fifo_empty ), /* output logic */ .full (packet_fifo_full ) );

assign axis_in.axis_tready = !packet_fifo_full && !data_fifo_full; assign axis_out.axis_tvalid = !packet_fifo_empty && !data_fifo_empty; //—<< PACKET >>————————————– //—>> bytes counter <<——————————- logic reset_w_bytes; assign #1 reset_w_bytes = axis_in.axis_tvalid && axis_in.axis_tlast && axis_in.axis_tready;

always@(posedge axis_in.aclk,negedge axis_in.aresetn)

if(~axis_in.aresetn)    w_bytes_total   <= '0;
else begin
    // if(axis_in.axis_tvalid && axis_in.axis_tlast && axis_in.axis_tready)
    if(reset_w_bytes)
            w_bytes_total   <= '0;
    else if(axis_in.axis_tvalid && axis_in.axis_tready)
            w_bytes_total   <= w_bytes_total + 1'b1;
    else    w_bytes_total   <= w_bytes_total;
end

logic [15:0] out_cnt;

always@(posedge axis_out.aclk,negedge axis_out.aresetn)

if(~axis_out.aresetn)   out_cnt <= '0;
else begin
    if(axis_out.axis_tvalid && axis_out.axis_tlast && axis_out.axis_tready)
            out_cnt   <= '0;
    else if(axis_out.axis_tvalid && axis_out.axis_tready)
            out_cnt   <= out_cnt + 1'b1;
    else    out_cnt   <= out_cnt;
end

//—<< bytes counter >>——————————- //—>> READ LAST <<———————————– logic native_last;

always@(posedge axis_out.aclk,negedge axis_out.aresetn)

if(~axis_out.aresetn) native_last   <= 1'b0;
else begin
    if(axis_out.axis_tvalid && native_last && axis_out.axis_tready)
            native_last <= 1'b0;
    else if(out_cnt == (r_bytes_total-1) && axis_out.axis_tvalid  && axis_out.axis_tready)
            native_last <= 1'b1;
    else    native_last <= native_last;
end

assign axis_out.axis_tlast = native_last || r_total_eq_1; //—<< READ LAST >>———————————– endmodule