Index: firmware/App/Services/SystemCommMessages.h
===================================================================
diff -u -rd47a7266da716ae65dd414b50002d72cb38f63fb -ref1d6b657a58e367d823e09bfbf38cb52552d64f
--- firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision d47a7266da716ae65dd414b50002d72cb38f63fb)
+++ firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision ef1d6b657a58e367d823e09bfbf38cb52552d64f)
@@ -63,6 +63,80 @@
 
 #define ACK_REQUIRED                    TRUE                ///< Macro for functions that want to know if an outgoing message requires acknowledgement from receiver.
 #define ACK_NOT_REQUIRED                FALSE               ///< Macro for functions that want to know if an outgoing message requires acknowledgement from receiver.
+
+
+
+typedef struct
+{
+    U08 acknowledgement;         ///< Acknowledgement Byte
+} ACK_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    BOOL accepted;              ///< Accepted/Rejected
+    U32 rejectionReason;        ///< Rejection reason if not accepted.
+} UI_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    U08 userRequest;            ///< request to confirm, cancel, or reject off button request
+} UI_OFF_BUTTON_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    U32 event;                  ///< Event ID
+    U32 dataType1;              ///< Data type for data field 1
+    EVENT_DATAS_T data1;        ///< data field 1
+    U32 dataType2;              ///< Data type for data field 2
+    EVENT_DATAS_T data2;        ///< Data field 2
+} EVENT_PAYLOAD_T;
+
+typedef struct
+{
+    BOOL accepted;              ///< Accepted/Rejected
+    U32 rejectionReason;        ///< Rejection reason if not accepted.
+    F32 ufVolume;               ///< UF Volume in mL.
+    U32 durationInMinutes;      ///< new Treatment duration in minutes.
+    S32 timeDiff;               ///< Treatment duration difference.
+    F32 ufRate;                 ///< new UF rate in mL/min.
+    F32 rateDiff;               ///< difference between new and old UF rates.
+    F32 oldUFRate;              ///< Previous UF Rate in mL/min.
+} UF_SETTINGS_CHANGE_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    BOOL accepted;              ///< Accepted/Rejected
+    U32 rejectionReason;        ///< Rejection reason if not accepted.
+    F32 volume;                 ///< UF Volume in mL.
+    U32 duration;               ///< Treatment duration in minutes
+    F32 ufRate;                 ///< UF rate in mL.
+} UF_SETTINGS_CONFIRMATION_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    BOOL accepted;              ///< Accepted/Rejected
+    U32 rejectionReason;        ///< Rejection reason if not accepted.
+    U32 duration;               ///< Treatment duration in minutes
+    F32 volume;                 ///< UF Volume in mL.
+} TREATMENT_TIME_CHANGE_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    BOOL accepted;              ///< Accepted/Rejected
+    U32 rejectionReason;        ///< Rejection reason if not accepted.
+    U32 bloodRate;              ///< new blood flow rate
+    U32 dialRate;               ///< new dialysate flow rate
+} BLOOD_DIAL_RATE_CHANGE_RESPONSE_PAYLOAD_T;
+
+typedef struct
+{
+    U32 minTreatmentTime;       ///< Minimum treatment duration (in minutes)
+    U32 maxTreatmentTime;       ///< Maximum treatment duration (in minutes)
+    F32 minUFVolume;            ///< Minimum ultrafiltration volume (in mL)
+    F32 maxUFVolume;            ///< Maximum ultrafiltration volume (in mL)
+    U32 minDialRate;            ///< Minimum dialysate flow rate (in mL/min)
+    U32 maxDialRate;            ///< Maximum dialysate flow rate (in mL/min)
+} TREATMENT_PARAM_BROADCAST_PAYLOAD_T;
 
 // ********** public function prototypes **********