diff --git a/equipment.py b/equipment.py
index 58617fc..2f81ff0 100644
--- a/equipment.py
+++ b/equipment.py
@@ -2,15 +2,13 @@ from collections import defaultdict
 from trytond.pool import Pool
 from trytond.model import (
     Workflow, ModelSQL, ModelView, Unique, fields)
-from trytond.pyson import Eval
+from trytond.pyson import Eval, If
 from trytond.exceptions import UserError
 
 class OpticalEquipment(Workflow, ModelSQL, ModelView):
     'Optical Equipment'
     __name__ = 'optical_equipment.equipment'
 
-    code_readonly = fields.Function(
-        fields.Boolean("Code Readonly"), 'get_code_readonly')
 
     code = fields.Char(
         "Code", select=True,states={'readonly': True })
@@ -54,10 +52,6 @@ class OpticalEquipment(Workflow, ModelSQL, ModelView):
                         states={'readonly': True})
     
     current_subscription = fields.Many2One('sale.subscription')
-    
-    @staticmethod
-    def get_origin():
-        return None
 
     @classmethod
     def __setup__(cls):
@@ -72,32 +66,30 @@ class OpticalEquipment(Workflow, ModelSQL, ModelView):
             ('registred', 'contrated'),
             })
         cls._buttons.update({
-            'draft': {},
-            'registred': {}})
-        
+            'draft': {
+                'invisible': Eval('state') == 'draft'},
+            'registred': {
+                'invisible': Eval('state').in_(['registred', 'contrated'])}}
+        )
 
-    def default_code_readonly(cls):
+    @classmethod
+    def set_code(cls, equipments):
         pool = Pool()
-        Configuration = pool.get('optical_equipment.configuration')
-        config = Configuration(1)
-        return bool(config.equipment_sequence)
-
-    def get_code_readonly(self, name):
-        return self.default_code_readonly()
-
+        Config = pool.get('optical_equipment.configuration')
+        config = Config(1)
+        for equipment in equipments:
+            if not equipment.code:
+                try:
+                    equipment.code = config.equipment_sequence.get()
+                    equipment.state = 'registred'
+                    cls.save(equipments) #Revisar
+                except UserError:
+                    raise UserError(str('Validation Error'))
+                
     @classmethod
     def default_state(cls):
        return 'draft'
-
-    @classmethod
-    def _new_code(cls):
-        pool = Pool()
-        Configuration = pool.get('optical_equipment.configuration')
-        config = Configuration(1)
-        sequence = config.equipment_sequence
-        if sequence:
-            return sequence.get()
-
+   
     @classmethod
     @ModelView.button
     @Workflow.transition('draft')
@@ -109,4 +101,7 @@ class OpticalEquipment(Workflow, ModelSQL, ModelView):
     @ModelView.button
     @Workflow.transition('registred')
     def registred(cls, equipments):
-        pass
+        #raise UserError(str(equipments))
+        cls.set_code(equipments)
+        #state = 'registred'
+