1 files changed, 162 insertions, 0 deletions
diff --git a/nandgame/alu_tb.sv b/nandgame/alu_tb.sv
new file mode 100644
index 0000000..cb5bfa5
--- /dev/null
+++ b/nandgame/alu_tb.sv
@@ -0,0 +1,162 @@
+`timescale 1us/1us
+
+`include "nandgame_types.v"
+
+module alu_tb;
+
+logic [15:0] in1;
+logic [15:0] in2;
+logic [1:0] opcode;
+logic [15:0] result;
+logic u, zx, sw;
+
+alu uut (
+  .X(in1),
+  .Y(in2),
+  .opcode(opcode),
+  .RES(result),
+  .u(u),
+  .zx(zx),
+  .sw(sw)
+);
+
+string filename;
+initial begin
+`ifdef DUMP_FILE_NAME
+  filename=`DUMP_FILE_NAME;
+`else
+  filename="alu.lxt2";
+`endif
+  $dumpfile(filename); $dumpvars();
+end
+
+initial begin
+  zx = 0;
+  sw = 0;
+
+  // Arith tests
+  u = 1;
+  in1 = 13;
+  in2 = 17;
+  opcode = ARITH_PLUS;
+  #1
+  assert(result == 30)
+  else $error("Expected: 30, got: %d", result);
+  #1
+  in1 = 12;
+  in2 = 4;
+  opcode = ARITH_MINUS;
+  #1
+  assert(result == 8)
+  else $error("Expected: 8, got: %d", result);
+  #1
+  in1 = 12;
+  in2 = 13;
+  opcode = ARITH_MINUS;
+  #1
+  assert(result == 16'hffff)
+  else $error("Expected: 16'hffff, got: %d", result);
+  #1
+  in1 = 13;
+  in2 = 17;
+  opcode = ARITH_INC;
+  #1
+  assert(result == 14)
+  else $error("Expected: 14, got: %d", result);
+  #1
+  in1 = 13;
+  in2 = 17;
+  opcode = ARITH_DEC;
+  #1
+  assert(result == 12)
+  else $error("Expected: 12, got: %d", result);
+  #1
+  in1 = 0;
+  in2 = 17;
+  opcode = ARITH_DEC;
+  #1
+  assert(result == 16'hffff)
+  else $error("Expected: 16'hffff, got: %d", result);
+  #1
+
+  // logic tests
+  u  = 0;
+  in1 = 16'b1010;
+  in2 = 16'b1100;
+  opcode = LOGIC_AND;
+  #1
+  assert(result == 16'b1000)
+  else $error("Expected: 16'b1000, got: %d", result);
+  #1
+  in1 = 16'b1010;
+  in2 = 16'b1100;
+  opcode = LOGIC_OR;
+  #1
+  assert(result == 16'b1110)
+  else $error("Expected: 16'b1110, got: %d", result);
+  #1
+  in1 = 16'b1010;
+  in2 = 16'b1100;
+  opcode = LOGIC_XOR;
+  #1
+  assert(result == 16'b0110)
+  else $error("Expected: 16'b0110, got: %d", result);
+  #1
+  in1 = 16'b1010101010101010;
+  opcode = LOGIC_NEGT;
+  #1
+  assert(result == 16'b0101010101010101)
+  else $error("Expected: 16'b0101010101010101, got: %d", result);
+  #1
+
+  // zero - tests
+  zx = 1;
+  sw = 0;
+  // back to logic
+  u = 0;
+  in1 = 2;
+  in2 = 4;
+  opcode = LOGIC_OR;
+  #1
+  assert(result == 4)
+  else $error("Expected 4, got %d", result);
+  #1
+
+  // back to arith
+  u = 1;
+  in1 = 2;
+  in2 = 4;
+  opcode = ARITH_PLUS;
+  #1
+  assert(result == 4)
+  else $error("Expected 4, got %d", result);
+  #1
+
+  // swap tests
+  zx = 0;
+  sw = 1;
+  u = 1;
+  in1 = 2;
+  in2 = 3;
+  opcode = ARITH_MINUS;
+  #1
+  // 3 - 2
+  assert(result == 1)
+  else $error("Expected 1, got %d", result);
+
+  // zero-swap
+  zx = 1;
+  sw = 1;
+  u = 1;
+  in1 = 2;
+  in2 = 3;
+  opcode = ARITH_PLUS;
+  #1
+  // 2 + 0
+  assert(result == 2)
+  else $error("Expected 2, got %d", result);
+
+  $finish();
+end
+
+endmodule