--- nand.py-
+++ nand.py
@@ -94,6 +94,73 @@
 			if pin.conn:
 				pin.set(v)
 
+class NOT(Obj):
+	def __init__(self, parent, name='not_', latency=10):
+		Obj.__init__(self, parent, name)
+		NAND(self, 'nand', latency)
+		Pin(self, 'inp').conn = self.nand.inp_a
+		Pin(self, 'H', 'H').conn = self.nand.inp_b
+		self.nand.out.conn = Pin(self, 'out')
+
+class AND(Obj):
+	def __init__(self, parent, name='and_', latency=10):
+		Obj.__init__(self, parent, name)
+		NAND(self, 'nand', latency)
+		Pin(self, 'inp_a').conn = self.nand.inp_a
+		Pin(self, 'inp_b').conn = self.nand.inp_b
+		NOT(self, 'not_', latency)
+		self.nand.out.conn = self.not_.inp
+		self.not_.out.conn = Pin(self, 'out')
+
+class OR(Obj):
+	def __init__(self, parent, name='or_', latency=10):
+		Obj.__init__(self, parent, name)
+		NOT(self, 'not_a', latency)
+		Pin(self, 'inp_a').conn = self.not_a.inp
+		NOT(self, 'not_b', latency)
+		Pin(self, 'inp_b').conn = self.not_b.inp
+		NAND(self, 'nand', latency)
+		self.not_a.out.conn = self.nand.inp_a
+		self.not_b.out.conn = self.nand.inp_b
+		self.nand.out.conn = Pin(self, 'out')
+
+class NOR(Obj):
+	def __init__(self, parent, name='nor', latency=10):
+		Obj.__init__(self, parent, name)
+		OR(self, 'or_', latency)
+		Pin(self, 'inp_a').conn = self.or_.inp_a
+		Pin(self, 'inp_b').conn = self.or_.inp_b
+		NOT(self, 'not_', latency)
+		self.or_.out.conn = self.not_.inp
+		self.not_.out.conn = Pin(self, 'out')
+
+class XOR(Obj):
+	def __init__(self, parent, name='xor', latency=10):
+		Obj.__init__(self, parent, name)
+		NAND(self, 'nand_i', latency)
+		NAND(self, 'nand_a', latency)
+		NAND(self, 'nand_b', latency)
+		NAND(self, 'nand_o', latency)
+		Joint(self, 'jt_a')
+		Joint(self, 'jt_b')
+		Joint(self, 'jt_c')
+
+		Pin(self, 'inp_a').conn = self.jt_a.new_pin()
+		self.jt_a.new_pin().conn = self.nand_i.inp_a
+		self.jt_a.new_pin().conn = self.nand_a.inp_a
+
+		Pin(self, 'inp_b').conn = self.jt_b.new_pin()
+		self.jt_b.new_pin().conn = self.nand_i.inp_b
+		self.jt_b.new_pin().conn = self.nand_b.inp_b
+
+		self.nand_i.out.conn = self.jt_c.new_pin()
+		self.jt_c.new_pin().conn = self.nand_a.inp_b
+		self.jt_c.new_pin().conn = self.nand_b.inp_a
+
+		self.nand_a.out.conn = self.nand_o.inp_a
+		self.nand_b.out.conn = self.nand_o.inp_b
+		self.nand_o.out.conn = Pin(self, 'out')
+
 class Lamp(Obj):
 	def __init__(self, parent, name='lamp', latency=None):
 		Obj.__init__(self, parent, name, latency)
@@ -133,6 +200,7 @@
 		while self.run:
 			cmd_exec( sys.stdin )
 			if self.que:
+				#dbgout( 'que={}'.format(self.que) )
 				(tm, f, args) = self.que.pop(0)
 				self.now = tm
 				f(*args)