41 lines
1.4 KiB
VHDL
41 lines
1.4 KiB
VHDL
|
library IEEE;
|
||
|
|
use IEEE.STD_LOGIC_1164.ALL;
|
||
|
|
|
||
|
|
entity Stack is
|
||
|
|
Port (
|
||
|
|
push : in STD_LOGIC; -- Signal to push data onto the stack
|
||
|
|
pop : in STD_LOGIC; -- Signal to pop data from the stack
|
||
|
|
data_in : in STD_LOGIC_VECTOR(7 downto 0); -- Input data to be pushed onto the stack
|
||
|
|
data_out: out STD_LOGIC_VECTOR(7 downto 0) -- Data popped from the stack
|
||
|
|
);
|
||
|
|
end Stack;
|
||
|
|
|
||
|
|
architecture Behavioral of Stack is
|
||
|
|
type Stack_Type is array (0 to 7) of STD_LOGIC_VECTOR(7 downto 0);
|
||
|
|
signal stack_memory : Stack_Type;
|
||
|
|
signal stack_pointer: STD_LOGIC_VECTOR(2 downto 0) := "000"; -- Initial stack pointer
|
||
|
|
|
||
|
|
begin
|
||
|
|
process (push, pop, data_in)
|
||
|
|
begin
|
||
|
|
if push = '1' then
|
||
|
|
if stack_pointer = "111" then
|
||
|
|
-- Stack is full, no more pushing allowed
|
||
|
|
report "Stack Overflow";
|
||
|
|
else
|
||
|
|
stack_memory(to_integer(unsigned(stack_pointer))) <= data_in;
|
||
|
|
stack_pointer <= stack_pointer + 1;
|
||
|
|
end if;
|
||
|
|
elsif pop = '1' then
|
||
|
|
if stack_pointer = "000" then
|
||
|
|
-- Stack is empty, no more popping allowed
|
||
|
|
report "Stack Underflow";
|
||
|
|
else
|
||
|
|
stack_pointer <= stack_pointer - 1;
|
||
|
|
end if;
|
||
|
|
end if;
|
||
|
|
end process;
|
||
|
|
|
||
|
|
data_out <= stack_memory(to_integer(unsigned(stack_pointer))); -- Output the data from the stack
|
||
|
|
end Behavioral;
|