| /* |
| * Copyright (c) 2001 Ted Bullen |
| * |
| * This source code is free software; you can redistribute it |
| * and/or modify it in source code form under the terms of the GNU |
| * General Public License as published by the Free Software |
| * Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA |
| */ |
| // This code is released to Steve Williams for the Icarus Verilog compiler |
| // It can be used as desired ! |
| |
| |
| // DEFINES |
| `define NRBITS 4 // Number of bits in each operand |
| |
| // TOP MODULE |
| module testFunction(); |
| |
| // SIGNAL DECLARATIONS |
| reg clock; |
| reg [`NRBITS-1:0] a_in; |
| integer a_integer; |
| integer myint; |
| reg [`NRBITS:0] cycle_count; // Counts valid clock cycles |
| |
| // Initialize inputs |
| initial begin |
| clock = 1; |
| cycle_count = 0; |
| # (16*200+15) $display("PASSED"); |
| $finish; |
| end |
| |
| // Generate the clock |
| always #100 clock = ~clock; |
| |
| // Simulate |
| always @(negedge clock) begin |
| cycle_count = cycle_count + 1; |
| |
| // Create inputs between 0 and all 1s |
| a_in = cycle_count[`NRBITS-1:0]; |
| myint = a_in; |
| $display("a_in = %d, myint = %d", a_in, myint); |
| |
| // Convert the unsigned numbers to signed numbers |
| a_integer = short_to_int(a_in); |
| |
| |
| if (myint !== a_integer) |
| begin |
| $display("ERROR ! %d !== %d", myint, a_integer); |
| $stop; |
| end |
| end |
| |
| // Function to convert a reg of `NRBITS |
| // bits to a signed integer |
| function integer short_to_int; |
| |
| input [`NRBITS-1:0] x; |
| begin |
| short_to_int = x; |
| $display("\tshort_to_int(%b) = %b", x, short_to_int); |
| end |
| endfunction |
| endmodule |