Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r7b88c9005b538ceb13de34212fb5be0a020f0dec -r6530db1926d689b51c2f5fcd6ae928c40ebf5f42
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 7b88c9005b538ceb13de34212fb5be0a020f0dec)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 6530db1926d689b51c2f5fcd6ae928c40ebf5f42)
@@ -7,8 +7,8 @@
 *
 * @file    SystemCommMessages.c
 *
-* @author  (last)      Dara Navaei
-* @date    (last)      03-Feb-2023
+* @author  (last)      Michael Garthwaite
+* @date    (last)      20-Mar-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -484,7 +484,7 @@
 
     // create a message record
     blankMessage( &msg );
-    msg.hdr.msgID = MSG_ID_DG_VERSION;
+    msg.hdr.msgID = MSG_ID_DG_VERSION_REPONSE;
     msg.hdr.payloadLen = sizeof( DG_VERSIONS_T );
 
     if ( message->hdr.payloadLen == sizeof( U08 ) + sizeof( U08 ) + sizeof( U08 ) + sizeof( U16 ) + sizeof( U32 ) )
@@ -502,7 +502,7 @@
     }
 
     // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
-    serializeMessage( msg, COMM_BUFFER_OUT_CAN_DG_BROADCAST, ACK_NOT_REQUIRED );
+    serializeMessage( msg, COMM_BUFFER_OUT_CAN_DG_BROADCAST, ACK_REQUIRED );
 }
 
 /*********************************************************************//**
@@ -526,7 +526,7 @@
 
     // Create a message record
     blankMessage( &msg );
-    msg.hdr.msgID = MSG_ID_DG_SERIAL_NUMBER;
+    msg.hdr.msgID = MSG_ID_DG_SERIAL_NUMBER_RESPONSE;
 
     // Add 1 byte for null terminator
     msg.hdr.payloadLen = MAX_TOP_LEVEL_SN_CHARS + 1;
@@ -1676,7 +1676,7 @@
     getCPLDStatus( &payload );
     // create a message record
     blankMessage( &msg );
-    msg.hdr.msgID = MSG_ID_DG_CPLD_STATUS;
+    msg.hdr.msgID = MSG_ID_DG_CPLD_STATUS_DATA;
     msg.hdr.payloadLen = sizeof( CPLD_STATUS_T );
 
     // fill message payload
@@ -4268,7 +4268,7 @@
         memcpy( &payload, message->payload, sizeof( TEST_OVERRIDE_PAYLOAD_T ) );
         if ( FALSE == payload.reset )
         {
-            result = testSetIntegratedVolumeOverride( payload.state.u32 );
+            result = testSetIntegratedVolumeOverride( payload.state.f32 );
         }
         else
         {
@@ -4392,7 +4392,8 @@
     BOOL result = FALSE;
 
     // verify payload length
-    if ( sizeof( U32 ) == message->hdr.payloadLen )
+    if ( ( sizeof( U32 ) == message->hdr.payloadLen ) &&
+         ( ( DG_MODE_STAN == getCurrentOperationMode() ) || ( DG_MODE_SOLO == getCurrentOperationMode() ) ) )
     {
         NELSON_SUPPORT_T nelson;
 
@@ -4413,11 +4414,6 @@
                 requestNewOperationMode( DG_MODE_HEAT );
                 break;
 
-            case NELSON_POS_CONTROL_CHEM_DISINFECT:
-                setChemNelsonSupportMode( nelson );
-                requestNewOperationMode( DG_MODE_CHEM );
-                break;
-
             case NELSON_POS_CONTROL_HEAT_DISINFECT:
                 setHeatNelsonSupportMode( nelson );
                 requestNewOperationMode( DG_MODE_HEAT );