diff --git a/simulator/serial.py b/simulator/serial.py
index e73c01b..61c3f3d 100644
--- a/simulator/serial.py
+++ b/simulator/serial.py
@@ -9,10 +9,19 @@ class Serial:
 		self.baudrate = baudrate
 		self.timeout  = timeout
 
-	def read(self, count):
+	def gen_key(self, count):
 		lst = [random.choice(string.hexdigits) for n in range(count - 2)]
-		ret = "A" + "".join(lst) + "D"
-		return ret.encode()
+		return "A" + "".join(lst) + "D"
+
+	def read(self, count):
+		val = random.randint(0, 4)
+		if val == 0 or val == 1:
+			return "".encode()
+		elif val == 2 or val == 3:
+			ret = self.gen_key(count)
+			print("> Serial generating key: %s" % ret)
+			return ret.encode()
+		raise Exception("Test Serial Exception")
 
 	def flushInput(self):
 		pass
diff --git a/simulator/urllib/request.py b/simulator/urllib/request.py
index ba5f258..8efdc67 100644
--- a/simulator/urllib/request.py
+++ b/simulator/urllib/request.py
@@ -13,12 +13,12 @@ class Request:
 		pass
 
 	def read(self):
-		val = random.randint(0, 2)
-		if val == 0:
+		val = random.randint(0, 4)
+		if val == 0 or val == 1:
 			return "OK".encode()
-		elif val == 1:
+		elif val == 2 or val == 3:
 			return "ERROR".encode()
-		raise Exception('Test Exception')
+		raise Exception("Test Network Exception")
 
 
 def urlopen(url):