Terminal.v

   1 module Terminal(
   2         input clk,
   3
   4         input cp_req,
   5         input [31:0] cp_insn,
   6         output reg cp_ack,
   7         output reg cp_busy,
   8         input cp_rnw,
   9         output reg [31:0] cp_read = 0,
  10         input [31:0] cp_write);
  11
  12         /* Terminal pretends to be cp5. */
  13         reg towrite = 0;
  14         reg [7:0] data = 0;
  15
  16         always @(*)
  17         begin
  18                 towrite = 0;
  19                 data = 8'hxx;
  20                 cp_ack = 0;
  21                 cp_busy = 0;
  22                 if (cp_req && (cp_rnw == 0) && (cp_insn[27:24] == 4'b1110) && (cp_insn[19:16] == 4'b0000) && (cp_insn[11:8] == 4'h5))
  23                 begin
  24                         towrite = 1;
  25                         data = cp_write[7:0];
  26                         cp_ack = 1;
  27                 end
  28         end
  29 `ifdef verilator
  30         always @(posedge clk)
  31                 if (towrite)
  32                         $c("{extern void term_output(unsigned char d); term_output(",data,");}");
  33 `endif
  34 endmodule