Index: dialin/protocols/CAN.py
===================================================================
diff -u -ra7d070474341dfa2f6012fc0acb000e14f413979 -r583690fad2c1791648961ce927d191ff7eb421f2
--- dialin/protocols/CAN.py	(.../CAN.py)	(revision a7d070474341dfa2f6012fc0acb000e14f413979)
+++ dialin/protocols/CAN.py	(.../CAN.py)	(revision 583690fad2c1791648961ce927d191ff7eb421f2)
@@ -432,7 +432,7 @@
     START_BYTE = DenaliMessage.START_BYTE
     DIALIN_MSG_RESP_TO = 0.1  # number of seconds to wait for a response to a sent command
 
-    def __init__(self, can_interface: str, logger: Logger, log_can=False, passive_mode=False):
+    def __init__(self, can_interface: str, logger: Logger, log_can=False, passive_mode=False, console_out=False):
         """
         DenaliCanMessenger constructor
 
@@ -442,12 +442,29 @@
         """
         super().__init__()
 
-        self.bus = can.interfaces.socketcan.SocketcanBus(channel=can_interface)
         self.logger = logger
         self.log_can = log_can
+
+        # try to setup can bus and exit if the can bus has not ben setup to use.
+        try:
+            self.bus = can.interfaces.socketcan.SocketcanBus(channel=can_interface)
+            if self.bus is not None:
+                self.serial_listener_thread = threading.Thread(target=self.listener, daemon=True)
+            else:
+                self.serial_listener_thread = None
+                s = "Can connection is not valid"
+                self.logger.debug(s)
+                sys.exit(s)
+            self.listener_buffer = can.BufferedReader()
+            self.notifier = can.Notifier(self.bus, [self.listener_buffer])
+        except Exception as e:
+            s = str(e)
+            self.logger.debug(s)
+            print(s)
+            sys.exit(19)
+
         self.passive_mode = passive_mode
-        self.listener_buffer = can.BufferedReader()
-        self.notifier = can.Notifier(self.bus, [self.listener_buffer])
+        self.console_out = console_out
         self.send_packet_request_id = -1
         self.send_event = threading.Event()
         self.long_message_builders = {}
@@ -459,13 +476,6 @@
         self.run = False
         self.sync_response_dictionary = {}
 
-        if self.bus is not None:
-            self.serial_listener_thread = threading.Thread(target=self.listener, daemon=True)
-
-        else:
-            self.serial_listener_thread = None
-            self.logger.debug("Can connection is not valid")
-
     def start(self):
         """
         starts listening to the can interface.
@@ -563,6 +573,8 @@
                                     DenaliMessage.crc8(self.messages)))
 
                         if message_valid:
+                            if self.console_out:
+                                print(complete_dialin_message)
                             # Send an ack if required
                             if DenaliMessage.get_sequence_number(complete_dialin_message) < 0:
                                 # ACK required. Send back the received message with the sequence sign bit flipped
Index: dialin/ui/hd_simulator.py
===================================================================
diff -u -r96006d22aa13f0287e2697a7cac7604201633263 -r583690fad2c1791648961ce927d191ff7eb421f2
--- dialin/ui/hd_simulator.py	(.../hd_simulator.py)	(revision 96006d22aa13f0287e2697a7cac7604201633263)
+++ dialin/ui/hd_simulator.py	(.../hd_simulator.py)	(revision 583690fad2c1791648961ce927d191ff7eb421f2)
@@ -727,7 +727,7 @@
 
         self.can_interface.send(message, 0)
 
-    def cmd_set_treatment_blood_flow_rate(self, vFlowSetPt, vMeasFlow, vRotSpd, vMotSpd, vMCSpd, vMCCurr, vPWM, vSigStrngth):
+    def cmd_set_treatment_blood_flow_rate(self, vFlowSetPt, vMeasFlow, vRotSpd, vMotSpd, vMCSpd, vMCCurr, vPWM, vSigStrength):
         """
         The Blood Flow Data message setter/sender method