Index: dialin/hd/hemodialysis_device.py
===================================================================
diff -u -radae506afce35a0063c6c2baf7e8580986f3bee7 -r1d0f0c1edb80ffa492f076bd5ead0729a64e17b1
--- dialin/hd/hemodialysis_device.py	(.../hemodialysis_device.py)	(revision adae506afce35a0063c6c2baf7e8580986f3bee7)
+++ dialin/hd/hemodialysis_device.py	(.../hemodialysis_device.py)	(revision 1d0f0c1edb80ffa492f076bd5ead0729a64e17b1)
@@ -60,6 +60,20 @@
     # HD login password
     HD_LOGIN_PASSWORD = '123'
 
+    # UI version message field positions
+    START_POS_MAJOR = DenaliMessage.PAYLOAD_START_INDEX
+    END_POS_MAJOR = START_POS_MAJOR + 1
+    START_POS_MINOR = END_POS_MAJOR
+    END_POS_MINOR = START_POS_MINOR + 1
+    START_POS_MICRO = END_POS_MINOR
+    END_POS_MICRO = START_POS_MICRO + 1
+    START_POS_BUILD = END_POS_MICRO
+    END_POS_BUILD = START_POS_BUILD + 2
+    START_POS_COMPATIBILITY_REV = END_POS_BUILD
+    END_POS_COMPATIBILITY_REV = START_POS_COMPATIBILITY_REV + 4
+
+
+
     def __init__(self, can_interface="can0", log_level=None):
         """
         HD object provides test/service commands for the HD sub-system.
@@ -91,13 +105,19 @@
             self.can_interface.register_receiving_publication_function(channel_id, msg_id,
                                                                        self._handler_hd_op_mode_sync)
 
+            self.can_interface.register_receiving_publication_function(DenaliChannels.ui_to_hd_ch_id,
+                                                                       MsgIds.MSG_ID_HD_UI_VERSION_INFO_RESPONSE.value,
+                                                                       self._handler_ui_version_response_sync)
+
         # create properties
         self.hd_operation_mode = HDOpModes.MODE_INIT.value
         self.hd_operation_sub_mode = 0
         self.hd_logged_in = False
         self.hd_set_logged_in_status(False)
         self.hd_no_transmit_msg_list = [0,0,0,0,0,0,0,0]
+        self.ui_version = None
 
+
         # Create command groups
         self.accel = HDAccelerometer(self.can_interface, self.logger)
         self.air_bubbles = HDAirBubbles(self.can_interface, self.logger)
@@ -181,6 +201,34 @@
         self.hd_operation_mode = mode[0]
         self.hd_operation_sub_mode = smode[0]
 
+    def _handler_ui_version_response_sync(self,message):
+        """
+        Handler for response from HD regarding its version.
+
+        @param message:  response message from HD regarding valid treatment parameter ranges.\n
+            U08  Major \n
+            U08  Minor \n
+            U08  Micro \n
+            U16  Build \n
+            U32 Compatibility revision
+
+        @return: None if not successful, the version string if unpacked successfully
+        """
+        major = struct.unpack('<B', bytearray(
+            message['message'][self.START_POS_MAJOR:self.END_POS_MAJOR]))
+        minor = struct.unpack('<B', bytearray(
+            message['message'][self.START_POS_MINOR:self.END_POS_MINOR]))
+        micro = struct.unpack('<B', bytearray(
+            message['message'][self.START_POS_MICRO:self.END_POS_MICRO]))
+        build = struct.unpack('<H', bytearray(
+            message['message'][self.START_POS_BUILD:self.END_POS_BUILD]))
+        compatibility = struct.unpack('<I', bytearray(
+            message['message'][self.START_POS_COMPATIBILITY_REV:self.END_POS_COMPATIBILITY_REV]))
+        self.logger.debug(f"handler hit.")
+        if all([len(each) > 0 for each in [major, minor, micro, build, compatibility]]):
+            self.ui_version = f"v{major[0]}.{minor[0]}.{micro[0]}-{build[0]}.{compatibility[0]}"
+            self.logger.debug(f"UI VERSION: {self.ui_version}")
+
     def cmd_log_in_to_hd(self, resend: bool = False) -> int:
         """
         Constructs and sends a login command via CAN bus.  Login required before \n
@@ -606,3 +654,18 @@
         else:
             self.logger.debug("Timeout!!!!")
             return False
+
+    def cmd_request_ui_version(self) -> None:
+        """
+        Constructs and sends a ui set standby submode to wait for disinfect
+
+        @return: none
+        """
+
+        message = DenaliMessage.build_message(channel_id=DenaliChannels.hd_to_ui_ch_id,
+                                              message_id=MsgIds.MSG_ID_HD_UI_VERSION_INFO_REQUEST.value)
+
+        self.logger.debug("Sending setting standby submode to wait for disinfect to HD.")
+        self.can_interface.send(message, 0)
+
+