From a330699a0e72e9ee92c586e10528799f38f25e13 Mon Sep 17 00:00:00 2001
From: Michael Geramb <mail@michael-geramb.at>
Date: Wed, 17 Apr 2024 19:21:27 +0200
Subject: [PATCH] Add function to group object to send a value only if it was
 changed.

---
 src/knx/group_object.cpp | 10 ++++++++++
 src/knx/group_object.h   | 13 +++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/src/knx/group_object.cpp b/src/knx/group_object.cpp
index 0abbfc0..5a9ad28 100644
--- a/src/knx/group_object.cpp
+++ b/src/knx/group_object.cpp
@@ -310,4 +310,14 @@ bool GroupObject::valueNoSendCompare(const KNXValue& value, const Dpt& type)
 
         return dataChanged;
     }
+}
+
+bool GroupObject::valueCompare(const KNXValue& value, const Dpt& type)
+{
+    if (valueNoSendCompare(value, type))
+    {
+         objectWritten();
+         return true;
+    }
+    return false;
 }
\ No newline at end of file
diff --git a/src/knx/group_object.h b/src/knx/group_object.h
index 38b8291..02bd0c3 100644
--- a/src/knx/group_object.h
+++ b/src/knx/group_object.h
@@ -173,6 +173,19 @@ class GroupObject
      * The parameters must fit the group object. Otherwise it will stay unchanged.
      */
     void value(const KNXValue& value, const Dpt& type);
+    
+    /**
+     * Check if the value (after conversion to dpt) will differ from current value of the group object and changes the state of the group object to ::WriteRequest if different.
+     * Use this method only, when the value should not be sent if it was not changed, otherwise value(const KNXValue&, const Dpt&) will do the same (without overhead for comparing)
+     * @param value the value the group object is set to
+     * @param type the datapoint type used for the conversion.
+     * 
+     * The parameters must fit the group object. Otherwise it will stay unchanged.
+     * 
+     * @returns true if the value of the group object has changed
+     */
+    bool valueCompare(const KNXValue& value, const Dpt& type);
+
     /**
      * set the current value of the group object.
      * @param value the value the group object is set to