--- nand.py-
+++ nand.py
@@ -357,17 +357,17 @@
 		self.jkff.Q.conn = Pin(self, 'Q')
 		self.jkff.nQ.conn = Pin(self, 'nQ')
 
-class DFF_N(Obj):
-	# D_x, CLK, Q_x
-	def __init__(self, parent, n, name='dff_n', latency=10):
+class LATCH(Obj):
+	# inp_x, CLK, out_x
+	def __init__(self, parent, n, name='latch', latency=10):
 		Obj.__init__(self, parent, name)
 		self.n = n
 		Pin(self, 'CLK', 'L').conn = Joint(self, 'jt_clk').new_pin()
 		for i in range(n):
 			dff_i = DFF( self, name_i('dff', i), latency )
 			self.jt_clk.new_pin().conn = dff_i.CLK
-			Pin( self, name_i('D', i), 'L' ).conn = dff_i.D
-			dff_i.Q.conn = Pin( self, name_i('Q', i), 'L' )
+			Pin( self, name_i('inp', i), 'L' ).conn = dff_i.D
+			dff_i.Q.conn = Pin( self, name_i('out', i), 'L' )
 
 class COUNTER(Obj):
 	# CLK, out_x
@@ -546,22 +546,29 @@
 			conn2_n( dbit_n, (self.pin_set, 'p', i * dbit_n), ( self.mux, name_i('inp', i), 0 ) )
 
 class CLK(Obj):
-	# en, out
-	def __init__(self, parent, hz=1.0, name='clk', pos=(0,0), lamp_name=None):
+	# en, out, Q, nQ
+	def __init__(self, parent, hz=1.0, name='clk', pos=(0,0), lamp_name=None, latency=10):
 		Obj.__init__(self, parent, name, None, pos)
-		latency = tm_from_fsec( 1.0 / ( 2 * hz ) )
-		NAND(self, 'nand', latency)
+		late = tm_from_fsec( 1.0 / ( 2 * hz ) )
+		NAND(self, 'nand', late)
 		Joint(self)
-		AND(self, 'and_')
+		NOT(self, 'not_', latency)
 
 		Pin(self, 'en', 'L').conn = Joint(self, 'jt_en').new_pin()
 		self.jt_en.new_pin().conn = self.nand.inp_a
 		self.nand.out.conn = self.jt.new_pin()
 		self.jt.new_pin().conn = self.nand.inp_b
-		self.jt.new_pin().conn = self.and_.inp_b
-		self.jt_en.new_pin().conn = self.and_.inp_a
-		self.and_.out.conn = Joint(self, 'jt_out').new_pin()
+		self.jt.new_pin().conn = self.not_.inp
+
+		GATE(self, 2, 'gate', latency)
+		self.jt_en.new_pin().conn = self.gate.en
+		self.jt.new_pin().conn = self.gate.inp_0
+		self.not_.out.conn = self.gate.inp_1
+
+		self.gate.out_1.conn = Pin(self, 'nQ')
+		self.gate.out_0.conn = Joint(self, 'jt_out').new_pin()
 		self.jt_out.new_pin().conn = Pin(self, 'out')
+		self.jt_out.new_pin().conn = Pin(self, 'Q')
 		if lamp_name:
 			self.jt_out.new_pin().conn = Lamp(self, lamp_name).inp
 
@@ -717,6 +724,11 @@
 		self.que = []
 		self.now = tm_tup(0)
 	
+	def enque_just(self, f, *args):
+		d = time.time() - self.start - tm_fsec( self.now )
+		tm = tm_from_fsec( d if d > 0 else 0 )
+		self.enque(tm, f, *args)
+
 	def enque(self, latency, f, *args):
 		if len(args) == 1 and type( args[0] ) == tuple:
 			args = args[0]
@@ -727,6 +739,8 @@
 
 		if self.exist_same(t):
 			return
+		for a in self.get_same_tm_f(t):
+			self.que.remove(a)
 
 		n = len(self.que)
 		while n > 0:
@@ -739,9 +753,13 @@
 	def exist_same(self, t):
 		return next( ( True for a in self.que if a == t ), False )
 
+	def get_same_tm_f(self, t):
+		same_tm_f = lambda (a_tm, a_f, a_a), (t_tm, t_f, t_a): a_tm == t_tm and a_f == t_f
+		return [ a for a in self.que if same_tm_f(a, t) ]
+
 	def main_loop(self):
 		self.run = True
-		start = time.time()
+		self.start = time.time()
 		while self.run:
 			cmd_exec( sys.stdin )
 			if self.que:
@@ -749,7 +767,7 @@
 				(tm, f, args) = self.que.pop(0)
 				self.now = tm
 				if '-f' not in sys.argv:
-					tm_sleep(tm, start)
+					tm_sleep(tm, self.start)
 				f(*args)
 			else:
 				time.sleep(0.5)