1 files changed, 72 insertions, 0 deletions
diff --git a/src/add1b_tb.vhd b/src/add1b_tb.vhd
new file mode 100644
index 0000000..18f05eb
--- /dev/null
+++ b/src/add1b_tb.vhd
@@ -0,0 +1,72 @@
+library ieee;
+library unisim;
+
+use ieee.std_logic_1164.all;
+use ieee.numeric_std.all;
+use unisim.vcomponents.all;
+
+entity add1b_tb is
+end add1b_tb;
+
+architecture behavioral of add1b_tb is
+component add1b
+port (
+	A: in std_logic;
+	B: in std_logic;
+	Cin: in std_logic;
+	X: out std_logic;
+	Cout: out std_logic);
+end component;
+
+signal A: std_logic;
+signal B: std_logic;
+signal Cin: std_logic;
+signal X: std_logic;
+signal Cout: std_logic;
+signal test_case: std_logic_vector(2 downto 0);
+signal ok: boolean := true;
+
+begin
+	test_port: add1b port map(
+		A => A,
+		B => B,
+		X => X,
+		Cout => Cout,
+		Cin => Cin);
+
+	tb: process
+		variable A_t: std_logic;
+		variable B_t: std_logic;
+		variable Cin_t: std_logic;
+		variable X_t: std_logic;
+		variable Cout_t: std_logic;
+		variable Out_t: std_logic_vector(1 downto 0);
+
+	begin
+		for i in 0 to 7 loop
+			test_case <= std_logic_vector(to_unsigned(i,3));
+			wait for 1 ps;
+	
+			A <= test_case(0);
+			B <= test_case(1);
+			Cin <= test_case(2);
+
+			A_t := test_case(0);
+			B_t := test_case(1);
+			Cin_t := test_case(2);
+
+			X_t := A_t xor B_t xor Cin_t;
+			Cout_t := (A_t and B_t) or (B_t and Cin_t) or (Cin_t and A_t);
+
+			wait for 5 ns;
+			If X /= X_t then
+				OK <= false;
+			end if;
+			if Cout /= Cout_t then
+				OK <= false;
+			end if;
+			wait for 5 ns;
+		end loop;
+		wait; -- stop for simulator
+	end process;
+end;