Honored Contributor
Honored ContributorSorry.. My bad. Here is the code and the .do file (at the buttom):
library ieee; use ieee.std_logic_1164.all; ENTITY FSM IS PORT (CLK : in std_logic; --Clock, active high RSTn : in std_logic; --Async. Reset, active low CoinIn : in std_logic_vector (1 downto 0) ; --Which coin was inserted Soda : out std_logic := '0'; --Is Soda dispensed ? CoinOut : out std_logic_vector (1 downto 0) --Which coin is dispensed? ); END ENTITY; ARCHITECTURE behavior of FSM IS TYPE state IS ( start, change, can, pending ); SIGNAL present_state, next_state : state; SIGNAL Count : integer range 0 to 6:=0; BEGIN PROCESS (RSTn, clk, CoinIn) --sync part BEGIN IF RSTn ='0' THEN present_state <= start; ELSIF rising_edge(clk) THEN present_state <= next_state; END IF; END PROCESS; PROCESS (CoinIn, clk, present_state, next_state) --combinational VARIABLE SodaVar : std_logic; VARIABLE CoinOutVar : std_logic_vector(1 downto 0); BEGIN CoinOutVar := "00"; CASE present_state is WHEN start => SodaVar := '0'; IF CoinIn = "01" then next_state <= pending; count <= 1; ELSIF CoinIn = "10" then next_state <= can; count <= 0; ELSIF CoinIn = "11" then next_state <= change; count <= 5; ELSIF CoinIn = "00" THEN next_state <= start; count <= 0; END IF; WHEN pending => SodaVar := '0'; IF CoinIn = "01" then next_state <= can; count <= 2; ELSIF CoinIn = "10" then next_state <= change; count <= 3; ELSIF CoinIn = "11" then next_state <= change; count <= 6; ELSIF CoinIn = "00" then next_state <= pending; END IF; WHEN change => SodaVar := '0'; IF ((count - 2) = 1) then CoinOutVar := "01"; count <= 0; next_State <= can; ELSIF ((count -2) = 0) then next_state <= can; count <= 0; CoinOutVar := "00"; ELSE next_state <= change; count <= count - 2; CoinOutVar := "10"; END IF; WHEN can => next_state <= start; SodaVar := '1'; count <= 0; END CASE; Soda <= SodaVar; CoinOut <= CoinOutVar; END PROCESS; END ARCHITECTURE; ------ THE DO FILE transcript off echo "------- START OF MACRO -------" onerror abort restart -force noview * add wave * view signals ;# ====== start of stimulus section ====== force clk 0 , 1 50 ns -r 100 ns force rstn 0 run 100 force rstn 1 force coinin 11 run 50 ns force coinin 00 ;# ======= end of stimulus section======= echo "------- END OF MACRO -------" echo "The time now is $now [ string trim $resolution 01 ] "