diff --git a/src/ast_to_c.ml b/src/ast_to_c.ml
index 52b439c..ff4e5f7 100644
--- a/src/ast_to_c.ml
+++ b/src/ast_to_c.ml
@@ -99,8 +99,8 @@ let pp_expression node_name =
     match expression with
     | EWhen (_, e1, e2) ->
         begin
-          (* as don't use a variable assigned when the condition holds, can define it even if the condition doesn't hold *)
-          Format.fprintf fmt "%a"
+          Format.fprintf fmt "%a ? %a : 0"
+            pp_expression_aux e2
             pp_expression_aux e1
         end
     | EReset (_, e1, e2) ->
diff --git a/src/main.ml b/src/main.ml
index 450e81d..e0c67f3 100644
--- a/src/main.ml
+++ b/src/main.ml
@@ -25,7 +25,7 @@ let exec_passes ast main_fn verbose debug passes f =
 
 let _ =
   (** Usage and argument parsing. *)
-  let default_passes = ["pre2vars"; "linearization"; "equations_ordering"] in
+	let default_passes = ["pre2vars"; "automata_validity" ;"automata_translation"; "linearization"; "equations_ordering"] in
   let sanity_passes = ["chkvar_init_unicity"; "check_typing"] in
   let usage_msg =
     "Usage: main [-passes p1,...,pn] [-ast] [-verbose] [-debug] \
@@ -67,6 +67,8 @@ let _ =
     [
       ("pre2vars", Passes.pre2vars);
       ("chkvar_init_unicity", Passes.chkvar_init_unicity);
+      ("automata_translation", Passes.automata_translation_pass);
+	  ("automata_validity", Passes.check_automata_validity);
       ("linearization", Passes.pass_linearization);
       ("equations_ordering", Passes.pass_eq_reordering);
       ("check_typing", Passes.pass_typing);
diff --git a/src/parser.mly b/src/parser.mly
index c6a1305..134a77d 100644
--- a/src/parser.mly
+++ b/src/parser.mly
@@ -199,7 +199,7 @@ node_content:
           n_local_vars = $10;
           n_equations  = eqs;
           n_automata = aut; } in
-      if List.length (snd $10) = 0 && node_name <> "main"
+      if List.length t_in = 0
         then raise (MyParsingError
                     (Format.asprintf "The node %s should have arguments."
                       node_name,
diff --git a/src/passes.ml b/src/passes.ml
index c206cce..a043d18 100644
--- a/src/passes.ml
+++ b/src/passes.ml
@@ -155,6 +155,22 @@ let chkvar_init_unicity verbose debug main_fn : t_nodelist -> t_nodelist option
   in
   node_pass aux
 
+let rec tpl debug ((pat, exp): t_equation) =
+  match exp with
+  | ETuple (_, hexps :: texps) ->
+      debug "An ETuple has been recognized, inlining...";
+      let p1, p2 =
+        list_select
+          (List.length (type_exp hexps))
+          (snd pat) in
+      let t1 = List.flatten (List.map type_var p1) in
+      let t2 = List.flatten (List.map type_var p2) in
+      ((t1, p1), hexps)
+        :: (tpl debug ((t2, p2),
+            ETuple (List.flatten (List.map type_exp texps), texps)))
+  | ETuple (_, []) -> []
+  | _ -> [(pat, exp)]
+
 let pass_linearization verbose debug main_fn =
   let node_lin (node: t_node): t_node option =
     let rec pre_aux_expression vars expr: t_eqlist * t_varlist * t_expression =
@@ -251,7 +267,7 @@ let pass_linearization verbose debug main_fn =
         n_name = node.n_name;
         n_inputs = node.n_inputs;
         n_outputs = node.n_outputs;
-        n_local_vars = new_locvars;
+        n_local_vars = node.n_local_vars;
         n_equations = new_equations;
         n_automata = node.n_automata;
       }
@@ -362,3 +378,151 @@ let pass_typing verbose debug main_fn ast =
           else None
   in aux ast
 
+let check_automata_validity verbos debug main_fn = 
+  let check_automaton_branch_vars automaton = 
+    let (init, states) = automaton in
+    let left_side = Hashtbl.create 10 in
+
+    let rec init_left_side eqlist = match eqlist with
+    | [] -> ()
+    | (varlist, exp)::q -> 
+        begin
+          Hashtbl.add left_side varlist true;
+          init_left_side q;
+        end
+    in
+    let check_state s = match s with
+    | State(name, eqs, cond, next) ->
+        List.for_all (fun (varlist, exp) -> (Hashtbl.mem left_side varlist)) eqs
+    in
+    begin
+    match init with | State(name, eqs, cond, next) -> init_left_side eqs;
+    let validity = List.for_all (fun s -> (check_state s)) states in
+    if not validity then
+      failwith "Automaton branch has different variables assignment in different branches"
+    end
+  in
+  let aux node = 
+    List.iter check_automaton_branch_vars node.n_automata;
+    Some node
+  in
+  node_pass aux
+
+let automaton_translation debug automaton = 
+  let gathered = Hashtbl.create 10 in
+  let state_to_int = Hashtbl.create 10 in
+  let add_to_table var exp state = 
+    if Hashtbl.mem gathered var then
+      let res = Hashtbl.find gathered var in
+      Hashtbl.replace gathered var ((state, exp)::res);
+    else
+      Hashtbl.replace gathered var ([(state, exp)])
+  in
+  let rec init_state_translation states c = match states with
+  | [] -> ()
+  | State(name, _, _, _)::q -> 
+      Hashtbl.replace state_to_int name c; (init_state_translation q (c+1))
+  in
+
+  let rec find_state name = 
+    match Hashtbl.find_opt state_to_int name with
+    | None -> failwith "Unknown state in automaton"
+    | Some v -> v
+  in
+
+  let rec equation_pass state : t_eqlist -> unit = function
+    | [] -> ()
+    | (vars, exp)::q -> begin
+      add_to_table vars exp state;
+      equation_pass state q
+    end
+  in
+
+  let flatten_state state = match state with
+  | State(name, eq, cond, next) -> 
+    (* Flattening is not possible
+       for example a branch where x,y = 1, 2 will be unpacked
+       when in another branch x, y = f(z) will not be unpacked
+    *)
+    (*
+    let new_equations = List.flatten
+      begin
+      List.map
+        (tpl debug)
+        eq
+      end in
+    *)
+    equation_pass name eq;
+    State(name, eq, cond, next)
+  in
+
+  let rec transition_eq states s = 
+    match states with
+    | [] -> EVar([TInt], IVar(s))
+    | State(name, eqs, cond, next)::q ->
+        let name = find_state name
+        and next = find_state next in
+        ETriOp([TInt], TOp_if, 
+          EBinOp([TBool], BOp_and, 
+            EComp([TBool], COp_eq,
+              EVar([TInt], IVar(s)),
+              EConst([TInt], CInt(name))
+            ),
+            cond
+          ),
+          EConst([TInt], CInt(next)),
+          transition_eq q s
+        )
+    in
+
+  let rec translate_var s v explist = match explist with
+  | [] -> EConst([TInt], CInt(0)) (* TODO *)
+  | (state, exp)::q -> 
+      ETriOp(Utils.type_exp exp, TOp_if,
+        EComp([TBool], COp_eq, 
+          EVar([TInt], IVar(s)),
+          EConst([TInt], CInt(Hashtbl.find state_to_int state))
+        ),
+        exp,
+        translate_var s v q
+      )
+  in
+
+  let flatten_automaton automaton = 
+    let (init, states) = automaton in
+    (flatten_state init, List.map flatten_state states)
+  in
+  let (init, states) = flatten_automaton automaton in
+  let s = create_automaton_name () in
+  init_state_translation states 1;
+  let exp_transition = EBinOp([TInt], BOp_arrow, EConst([TInt], CInt(1)), EMonOp([TInt], MOp_pre, transition_eq states s)) in
+  let new_equations = [(([TInt], [IVar(s)]), exp_transition)] in
+  Hashtbl.fold (fun var explist acc -> (var, translate_var s var explist)::acc) gathered new_equations, IVar(s)
+
+
+let automata_trans_pass debug (node:t_node) : t_node option=
+
+  let rec aux automaton = match automaton with
+  | [] -> [], [], []
+  | a::q -> 
+      let eq, var = automaton_translation debug a
+      and tail_eq, tail_var, tail_type = aux q in
+      eq@tail_eq, var::tail_var, TInt::tail_type
+  in
+
+  let eqs, vars, new_ty = aux node.n_automata in
+  let ty, loc_vars = node.n_local_vars in
+  Some
+    {
+      n_name = node.n_name;
+      n_inputs = node.n_inputs;
+      n_outputs = node.n_outputs;
+      n_local_vars = (new_ty@ty, vars@loc_vars);
+      n_equations = eqs@node.n_equations;
+      n_automata = []; (* not needed anymore *)
+    }
+
+let automata_translation_pass verbose debug main_fn = 
+  node_pass (automata_trans_pass debug)
+
+
diff --git a/src/passes_utils.ml b/src/passes_utils.ml
index 0e159d9..d7356a8 100644
--- a/src/passes_utils.ml
+++ b/src/passes_utils.ml
@@ -31,3 +31,8 @@ let expression_pass f: t_nodelist -> t_nodelist option =
   equation_pass aux
 
 exception PassExn of string
+
+let counter = ref 0
+let create_automaton_name : unit -> string = fun () ->
+    counter := !counter + 1;
+    Format.asprintf "_s%d" (!counter)
diff --git a/src/test.node b/src/test.node
index ef459bb..03d9db8 100644
--- a/src/test.node
+++ b/src/test.node
@@ -1,5 +1,4 @@
 node diagonal_int (i: int) returns (o1, o2 : int);
-var i: int;
 let
 	(o1, o2) = (i, i);
 tel
@@ -13,9 +12,10 @@ let
 tel
 
 node auto (i: int) returns (o : int);
+var x, y:int;
 let
 	automaton
-	| Incr -> do o = (pre o) + 1; done
-	| Decr -> do o = (pre o) - 1; done
+	| Incr -> do (o,x) = (0 fby o + 1, 2); done
+	| Decr -> do (o,x) = diagonal_int(0 fby o); done
 tel