Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r0295b0641d2f7eb2f61bf1d7901134cf9b893afb -rf3b83f75a19b975ad1abead662c8151a2907ac00
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 0295b0641d2f7eb2f61bf1d7901134cf9b893afb)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision f3b83f75a19b975ad1abead662c8151a2907ac00)
@@ -25,7 +25,6 @@
 #include "DialInFlow.h"
 #include "Dialysis.h"
 #include "FPGA.h"
-#include "MessagePayloads.h"
 #include "ModeStandby.h"
 #include "ModeTreatment.h"
 #include "ModeTreatmentParams.h"
@@ -407,8 +406,37 @@
     result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
 
     return result;
-}
-
+}
+
+/*********************************************************************//**
+ * @brief
+ * The sendChangePressureLimitsChangeResponse function constructs a change
+ * pressure limits response to the UI and queues the msg for transmit on the
+ * appropriate CAN channel.
+ * @details Inputs: none
+ * @details Outputs: Pressure limits change response msg constructed and queued.
+ * @param data response data record
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendChangePressureLimitsChangeResponse( PRESSURE_LIMIT_CHANGE_RESPONSE_T *data )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_HD_PRESSURE_LIMITS_CHANGE_RESPONSE;
+    msg.hdr.payloadLen = sizeof( PRESSURE_LIMIT_CHANGE_RESPONSE_T );
+
+    memcpy( payloadPtr, (U08*)data, sizeof( PRESSURE_LIMIT_CHANGE_RESPONSE_T ) );
+
+    // serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
+
+    return result;
+}
+
 /*********************************************************************//**
  * @brief
  * The sendTreatmentParamsRangesToUI function constructs a treatment parameter
@@ -1733,8 +1761,33 @@
     {
         sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, FALSE );
     }
-}
-
+}
+
+/*********************************************************************//**
+ * @brief
+ * The handleChangePressureLimitsRequest function handles a pressure limits
+ * change message from the UI.
+ * @details Inputs: none
+ * @details Outputs: message handled
+ * @param message a pointer to the message to handle
+ * @return none
+ *************************************************************************/
+void handleChangePressureLimitsRequest( MESSAGE_T *message )
+{
+    if ( sizeof( PRESSURE_LIMIT_CHANGE_REQUEST_T ) == message->hdr.payloadLen )
+    {
+        PRESSURE_LIMIT_CHANGE_REQUEST_T data;
+
+        memcpy( &data, &message->payload[0], sizeof(PRESSURE_LIMIT_CHANGE_REQUEST_T) );
+
+        verifyPressureLimitsChange( &data );
+    }
+    else
+    {
+        sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, FALSE );
+    }
+}
+
 /*********************************************************************//**
  * @brief
  * The handleDGOpMode function handles a DG broadcast of it's current mode.