Index: dialin/common/msg_defs.py
===================================================================
diff -u -r1fd5bc0ed97d0d90223fa78ec195dd7636712c5b -r8ba3986f8fe9ef801c9f592a37f90933effbd34d
--- dialin/common/msg_defs.py	(.../msg_defs.py)	(revision 1fd5bc0ed97d0d90223fa78ec195dd7636712c5b)
+++ dialin/common/msg_defs.py	(.../msg_defs.py)	(revision 8ba3986f8fe9ef801c9f592a37f90933effbd34d)
@@ -26,6 +26,8 @@
     MSG_DIALIN_ID_HD_SYSTEM_USAGE_RESPONSE  = 0x8A
     MSG_DIALIN_ID_DG_SYSTEM_USAGE_RESPONSE  = 0x8C
     MSG_DIALIN_ID_HD_DISINFECT_STATE        = 0x7E
+    MSG_DIALIN_ID_HD_VERSION_REQUEST        = 0x9E
+    MSG_DIALIN_ID_UI_POST_REPORT_VERSION    = 0x9F
 
 
 ACK_NOT_REQUIRED = [
Index: dialin/hd/valves.py
===================================================================
diff -u -r2e392c92d55178f457a67423ba8c503a86dcf3c8 -r8ba3986f8fe9ef801c9f592a37f90933effbd34d
--- dialin/hd/valves.py	(.../valves.py)	(revision 2e392c92d55178f457a67423ba8c503a86dcf3c8)
+++ dialin/hd/valves.py	(.../valves.py)	(revision 8ba3986f8fe9ef801c9f592a37f90933effbd34d)
@@ -291,7 +291,7 @@
             self.logger.debug("Opening air trap valve timeout!!")
             return False
 
-    @_publish(["valves_status"])
+    @_publish(["valves_status", "hd_air_trap_status"])
     def _handler_hd_valves_sync(self, message):
         """
         Handles published HD valves data messages.  HD valves data are captured
Index: dialin/ui/hd_simulator.py
===================================================================
diff -u -rdf207aa2b33d777cf082539d8b6547f4e97b5999 -r8ba3986f8fe9ef801c9f592a37f90933effbd34d
--- dialin/ui/hd_simulator.py	(.../hd_simulator.py)	(revision df207aa2b33d777cf082539d8b6547f4e97b5999)
+++ dialin/ui/hd_simulator.py	(.../hd_simulator.py)	(revision 8ba3986f8fe9ef801c9f592a37f90933effbd34d)
@@ -82,6 +82,9 @@
             self.can_interface.register_receiving_publication_function(DenaliChannels.ui_sync_broadcast_ch_id,
                                                                        MsgIdsDialin.MSG_DIALIN_ID_UI_SYSTEM_USAGE_REQUEST.value,
                                                                        self._handler_system_usage_response)
+            self.can_interface.register_receiving_publication_function(DenaliChannels.ui_to_hd_ch_id,
+                                                                       MsgIdsDialin.MSG_DIALIN_ID_UI_POST_REPORT_VERSION.value,
+                                                                       self._handler_ui_post_ui_version_compatibility)
         self.alarms_simulator = HDAlarmsSimulator(self.can_interface, self.logger)
 
         self.treatment_parameter_rejections = TreatmentParameterRejections()
@@ -1904,7 +1907,6 @@
         message = DenaliMessage.build_message(channel_id= DenaliChannels.hd_to_ui_ch_id,
                                               message_id=message_id,
                                               payload=payload)
-
         self.can_interface.send(message, 0)
 
     def cmd_ack_send_hd(self, seq: int) -> None:
@@ -1918,3 +1920,42 @@
                                               seq=seq)
 
         self.can_interface.send(message, 0)
+
+    def cmd_send_power_on_self_test_version_request(self) -> None:
+        """
+        Sends the power on self test version request
+
+        @return: None
+        """
+
+        payload = bytearray()
+        message = DenaliMessage.build_message(channel_id=DenaliChannels.hd_sync_broadcast_ch_id,
+                                              message_id=MsgIdsDialin.MSG_DIALIN_ID_HD_VERSION_REQUEST.value,
+                                              payload=payload)
+        self.can_interface.send(message, 0)
+
+    def _handler_ui_post_ui_version_compatibility(self, message: dict) -> None:
+        """
+        Handles the UI's reporting of its version during the power on self tests
+
+        @param message: The message data
+        @return: None
+        """
+
+        ui_major = struct.unpack('i', bytearray(
+            message['message'][MsgFieldPositions.START_POS_FIELD_1:MsgFieldPositions.END_POS_FIELD_1]))[0]
+        ui_minor = struct.unpack('i', bytearray(
+            message['message'][MsgFieldPositions.START_POS_FIELD_2:MsgFieldPositions.END_POS_FIELD_2]))[0]
+        ui_micro = struct.unpack('i', bytearray(
+            message['message'][MsgFieldPositions.START_POS_FIELD_3:MsgFieldPositions.END_POS_FIELD_3]))[0]
+        ui_build = struct.unpack('i', bytearray(
+            message['message'][MsgFieldPositions.START_POS_FIELD_4:MsgFieldPositions.END_POS_FIELD_4]))[0]
+        ui_compatibility = struct.unpack('i', bytearray(
+            message['message'][MsgFieldPositions.START_POS_FIELD_5:MsgFieldPositions.END_POS_FIELD_5]))[0]
+        self.logger.debug("UI version power on self test received: "
+                          "Major: {0} "
+                          "Minor: {1} "
+                          "Micro: {2} "
+                          "Build: {3} "
+                          "Compat: {4} "
+                          .format(ui_major, ui_minor, ui_micro, ui_build, ui_compatibility))
Index: dialin/ui/hd_simulator_alarms.py
===================================================================
diff -u -r46342bac3e23428e90666525bb5a89c4532da945 -r8ba3986f8fe9ef801c9f592a37f90933effbd34d
--- dialin/ui/hd_simulator_alarms.py	(.../hd_simulator_alarms.py)	(revision 46342bac3e23428e90666525bb5a89c4532da945)
+++ dialin/ui/hd_simulator_alarms.py	(.../hd_simulator_alarms.py)	(revision 8ba3986f8fe9ef801c9f592a37f90933effbd34d)
@@ -37,6 +37,7 @@
 
 class Alarms:
 
+    # TODO: this should be generated from FW
     # ALARM_ID = (priority, alarmID, escalates in, silent_espires_in, flags)
     ALARM_ID_NO_ALARM =                                 (NONE,  0,  0, 0, 0)
     ALARM_ID_SOFTWARE_FAULT =                           (HIGH,  1,  0, 0, 0)
Index: tests/peter/test_POST.py
===================================================================
diff -u -rb31694e714c45e0678632ab11efbcdcf6dbf6e96 -r8ba3986f8fe9ef801c9f592a37f90933effbd34d
--- tests/peter/test_POST.py	(.../test_POST.py)	(revision b31694e714c45e0678632ab11efbcdcf6dbf6e96)
+++ tests/peter/test_POST.py	(.../test_POST.py)	(revision 8ba3986f8fe9ef801c9f592a37f90933effbd34d)
@@ -25,9 +25,12 @@
 NUM_HD_TESTS = 8
 NUM_DG_TESTS = 6
 
-hd_sim = HDSimulator()
+hd_sim = HDSimulator(log_level="DEBUG")
 dg_sim = DGSimulator()
 
+# prompts UI to report version for the HD's version compatibility self test
+hd_sim.cmd_send_power_on_self_test_version_request()
+
 for _ in range(40):
     hd_sim.cmd_set_hd_operation_mode_data(HDOpModes.MODE_INIT.value, HDOpSubModes.SUBMODE_START.value)
     sleep(0.25)