Index: dialin/dg/calibration_record.py
===================================================================
diff -u -r20659ffd56482b0596253aa0f1f1a7eda1221945 -r46ebf93d3666db40f25ad1e9170426853aa845d4
--- dialin/dg/calibration_record.py	(.../calibration_record.py)	(revision 20659ffd56482b0596253aa0f1f1a7eda1221945)
+++ dialin/dg/calibration_record.py	(.../calibration_record.py)	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -72,6 +72,7 @@
 
         if not self._is_getting_cal_in_progress:
             self._is_getting_cal_in_progress = True
+            self._raw_cal_record.clear()
 
             message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
                                                   message_id=MsgIds.MSG_ID_DG_GET_CALIBRATION_RECORD.value)
@@ -85,7 +86,7 @@
 
             self.logger.debug("Timeout!!!!")
 
-        self.logger.debug("Request cancelled: an existing request is in progress.")
+        self.logger.warning("Request cancelled: an existing request is in progress.")
         return False
 
     def _handler_dg_calibration_sync(self, message):
Index: dialin/hd/ui_proxy.py
===================================================================
diff -u -r2e392c92d55178f457a67423ba8c503a86dcf3c8 -r46ebf93d3666db40f25ad1e9170426853aa845d4
--- dialin/hd/ui_proxy.py	(.../ui_proxy.py)	(revision 2e392c92d55178f457a67423ba8c503a86dcf3c8)
+++ dialin/hd/ui_proxy.py	(.../ui_proxy.py)	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -1219,7 +1219,7 @@
 
         self.can_interface.send(message, 0)
 
-    def set_a_treatment_parameter(self, param_idx, value):
+    def set_a_treatment_parameter(self, param_idx: int, value: int) -> None:
         """
         Constructs and sends a set treatment parameter message
         Constraints:
Index: dialin/protocols/CAN.py
===================================================================
diff -u -rbfb0c47181dc8a73d09825ab697a7799dd520417 -r46ebf93d3666db40f25ad1e9170426853aa845d4
--- dialin/protocols/CAN.py	(.../CAN.py)	(revision bfb0c47181dc8a73d09825ab697a7799dd520417)
+++ dialin/protocols/CAN.py	(.../CAN.py)	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -16,6 +16,7 @@
 
 import threading
 from collections import deque
+import asyncio
 
 import can
 import math
@@ -452,6 +453,7 @@
         # 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)
+            self.loop = asyncio.get_event_loop()
             if self.bus is not None:
                 self.canbus_thread = threading.Thread(target=self.listener, daemon=True)
                 self.message_queue_thread = threading.Thread(target=self.handle_messages, daemon=True)
@@ -460,8 +462,8 @@
                 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])
+            self.listener_buffer = can.AsyncBufferedReader()
+            self.notifier = can.Notifier(bus=self.bus, listeners=[self.listener_buffer], loop=self.loop)
         except Exception as e:
             s = str(e)
             self.logger.error(s)
@@ -491,7 +493,7 @@
             return
         else:
             self.run = True
-            if self.canbus_thread is not None:
+            if self.message_queue_thread is not None and self.canbus_thread is not None:
                 self.canbus_thread.start()
                 self.message_queue_thread.start()
                 self.logger.info("Can listener has started.")
@@ -510,17 +512,22 @@
         """
         Listens for diality message on the can interface passed during construction.
         """
+        async def _listener():
+            while True:
+                message = await self.listener_buffer.get_message()
 
-        while self.run:
+                if message is not None:
+                    self.message_queue.append(message)
 
-            message = self.listener_buffer.get_message(0.0)
+                else:  # no new packets in receive buffer
+                    # Careful here, making this any shorter will start limiting CPU time for other threads
+                    sleep(0.01)
 
-            if message is not None:
-                self.message_queue.append(message)
+        if not self.loop.is_running():
+            self.loop.run_until_complete(_listener())
+        else:
+            self.loop.create_task(_listener())
 
-            else:  # no new packets in receive buffer
-                # Careful here, making this any shorter will start limiting CPU time for other threads
-                sleep(0.01)
 
     def handle_messages(self):
         """
@@ -591,7 +598,7 @@
                             message_valid = False
                             dialin_ch_id = None
                             dialin_msg_id = None
-                            sys.stderr.write(
+                            self.logger.critical(
                                 "Incorrect CRC, received message: {}, crc: {}, calculated crc: {}\n".format(
                                     self.messages, DenaliMessage.get_crc(complete_dialin_message),
                                     DenaliMessage.crc8(self.messages)))
Index: tests/peter/test_blood_flow.py
===================================================================
diff -u -rbfb0c47181dc8a73d09825ab697a7799dd520417 -r46ebf93d3666db40f25ad1e9170426853aa845d4
--- tests/peter/test_blood_flow.py	(.../test_blood_flow.py)	(revision bfb0c47181dc8a73d09825ab697a7799dd520417)
+++ tests/peter/test_blood_flow.py	(.../test_blood_flow.py)	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -48,6 +48,7 @@
                                               payload=payload)
 
         hd_sim.can_interface.send(message, 0)
+        print("Sent", message)
         sleep(1)
 
 
Index: tests/peter/test_calibration.py
===================================================================
diff -u -rbfb0c47181dc8a73d09825ab697a7799dd520417 -r46ebf93d3666db40f25ad1e9170426853aa845d4
--- tests/peter/test_calibration.py	(.../test_calibration.py)	(revision bfb0c47181dc8a73d09825ab697a7799dd520417)
+++ tests/peter/test_calibration.py	(.../test_calibration.py)	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -1,3 +1,6 @@
+import copy
+import pprint
+import subprocess
 import sys
 import struct
 
@@ -10,6 +13,7 @@
 
 
 def process_calibration_record(read=False):
+    dg = DG()
 
     cal = dg.calibration_record
     print(cal.tmp_record)
@@ -74,6 +78,7 @@
     except KeyboardInterrupt:
         pass
 
+
 def test_crc():
     val = NVOpsUtils.crc_16(b''.join([
         struct.pack("<f", 0.0),
@@ -85,12 +90,56 @@
     ]))
     print(val)
     val = NVOpsUtils.crc_16(b''.join([
+        struct.pack("<f", 1.0), # fourth order
+        struct.pack("<f", 1.0), # third order
+        struct.pack("<f", 1.0), # second order
+        struct.pack("<f", 1.0), # gain
+        struct.pack("<f", 0.0), # offset
+        struct.pack("<i", 0), # cal_time
+    ]))
+    print(val)
+    """
+     OrderedDict([('ppi',
+                            {'cal_time': ['<i', 0],
+                             'crc': ['<H', 26600],
+                             'fourth_order': ['<f', 0.0],
+                             'gain': ['<f', 1.0],
+                             'offset': ['<f', 0.0],
+                             'second_order': ['<f', 0.0],
+                             'third_order': ['<f', 0.0]}),
+                           ('ppo',
+                            {'cal_time': ['<i', 0],
+                             'crc': ['<H', 26600],
+                             'fourth_order': ['<f', 0.0],
+                             'gain': ['<f', 1.0],
+                             'offset': ['<f', 0.0],
+                             'second_order': ['<f', 0.0],
+                             'third_order': ['<f', 0.0]}),
+    """
+    val = NVOpsUtils.crc_16(b''.join([
+        struct.pack("<f", 1.0),
+        struct.pack("<f", 1.0),
+        struct.pack("<f", 0),
+        struct.pack("<f", 0),
+        struct.pack("<i", 0), # calibration time
+    ]))
+    print(val)
+    val = NVOpsUtils.crc_16(b''.join([
+        struct.pack("<f", 1.0),
+        struct.pack("<f", 0),
+        struct.pack("<f", 0),
+        struct.pack("<f", 1.0),
+        struct.pack("<f", 0),
+        struct.pack("<i", 0),  # cal_time
+    ]))
+    print(val)
+    val = NVOpsUtils.crc_16(b''.join([
         struct.pack("<f", float("nan")),
         struct.pack("<f", float("nan")),
         struct.pack("<f", float("nan")),
         struct.pack("<f", float("nan")),
         struct.pack("<f", float("nan")),
-        struct.pack("<i", -1),
+        struct.pack("<i", -1),  # cal_time
     ]))
     print(val)
 
@@ -116,10 +165,40 @@
 
         print(dg.dg_version)
         print(dg.fpga_version)
+        # store the old record after reading it from fw
+        record_old_formatted = pprint.pformat(dg.calibration_record.dg_calibration_record, indent=4)
+        with open("/tmp/dialin_test_record_old.txt", 'w') as f:
+            f.write(record_old_formatted)
+        prev_value = dg.calibration_record.dg_calibration_record["pressure_sensors"]["ppi"]["fourth_order"][1]
+        print("Old Record setting: {0}".format(dg.calibration_record.dg_calibration_record["pressure_sensors"]["ppi"]["fourth_order"][1]))
 
+        # update the old record
+        if prev_value == 1:
+            new_value = 0.0
+        else:
+            new_value = 1.0
+
+        dg.calibration_record.dg_calibration_record["pressure_sensors"]["ppi"]["fourth_order"][1] = new_value
+        print("New record setting: {0}".format(dg.calibration_record.dg_calibration_record["pressure_sensors"]["ppi"]["fourth_order"][1]))
+
         dg.calibration_record.cmd_set_dg_calibration_record(dg.calibration_record.dg_calibration_record)
 
+        dg.calibration_record.cmd_request_dg_calibration_record()
+        observer.received = False
+        while not observer.received:
+            sleep(0.2)
 
+        # check that the old record is different from the new record
+        print("New record setting: {0}".format(dg.calibration_record.dg_calibration_record["pressure_sensors"]["ppi"]["fourth_order"][1]))
+
+        new_record_read = copy.deepcopy(dg.calibration_record.dg_calibration_record)
+        record_new_formatted = pprint.pformat(new_record_read, indent=4)
+        with open("/tmp/dialin_test_record_new.txt", 'w') as f:
+            f.write(record_new_formatted)
+
+        subprocess.call("meld /tmp/dialin_test_record_old.txt /tmp/dialin_test_record_new.txt", shell=True)
+
+
 def test_dg_service_record():
     dg = DG(log_level="DEBUG")
     if dg.cmd_log_in_to_dg():
@@ -210,9 +289,10 @@
     # test_dg_system_record()
     # test_dg_scheduled_runs_record()
 
-    test_hd_calibration_record()
+    # test_hd_calibration_record()
     # test_hd_service_record()
-    # test_hd_system_record()
+    test_hd_system_record()
+    # test_crc()
 
 
 
Index: tests/peter/test_can.py
===================================================================
diff -u -rbfb0c47181dc8a73d09825ab697a7799dd520417 -r46ebf93d3666db40f25ad1e9170426853aa845d4
--- tests/peter/test_can.py	(.../test_can.py)	(revision bfb0c47181dc8a73d09825ab697a7799dd520417)
+++ tests/peter/test_can.py	(.../test_can.py)	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -15,7 +15,7 @@
 ############################################################################
 import sys
 sys.path.append("..")
-from dialin.utils.base import setup_virtual_can_interface, setup_real_can_interface
+from dialin.utils import setup_virtual_can_interface, setup_real_can_interface
 
 resp = input("Setup virtual can interface? (y/n): ")
 if resp.lower() == "y":
Index: tests/peter/test_listener.py
===================================================================
diff -u
--- tests/peter/test_listener.py	(revision 0)
+++ tests/peter/test_listener.py	(revision 46ebf93d3666db40f25ad1e9170426853aa845d4)
@@ -0,0 +1,26 @@
+import sys
+import time
+sys.path.append("..")
+from dialin import HD, AbstractObserver
+
+
+class Observer(AbstractObserver):
+
+    def update(self, result):
+        print(result)
+
+def run():
+    """
+    Test if DG monitors valve states within every 500 ms
+    """
+    hd = HD(log_level="DEBUG")
+    observer = Observer()
+    hd.bloodflow.attach(observer)
+
+    while True:
+        print("Listening...")
+        time.sleep(1)
+
+
+if __name__ == "__main__":
+    run()