diff --git a/bacnet-stack/include/wpm.h b/bacnet-stack/include/wpm.h
index 7a607530..601bc5d2 100644
--- a/bacnet-stack/include/wpm.h
+++ b/bacnet-stack/include/wpm.h
@@ -29,8 +29,7 @@
 #include <stdbool.h>
 #include "bacdcode.h"
 #include "bacapp.h"
-
-
+#include "wp.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -49,6 +48,17 @@ extern "C" {
         BACNET_WRITE_PROPERTY_DATA * wpm_data);
 
 
+    /* encode objects */
+    int wpm_encode_apdu_init (uint8_t * apdu, uint8_t invoke_id);
+    int wpm_encode_apdu_object_begin (
+        uint8_t * apdu,
+        BACNET_OBJECT_TYPE object_type,
+        uint32_t object_instance);
+    int wpm_encode_apdu_object_end (uint8_t * apdu);
+    int wpm_encode_apdu_object_property (
+        uint8_t * apdu,
+        BACNET_WRITE_PROPERTY_DATA * wpdata);
+
     /* encode service */
     int wpm_ack_encode_apdu_init(
         uint8_t * apdu,
@@ -66,20 +76,20 @@ extern "C" {
 /** @defgroup DSWP Data Sharing - Write Property Multiple Service (DS-WPM)
  * @ingroup DataShare
  * 15.10 WriteProperty Multiple Service <br>
- * The WritePropertyMultiple service is used by a client BACnet-user 
- * to modify the value of one or more specified properties of a BACnet object. 
- * This service potentially allows write access to any property of any object, 
+ * The WritePropertyMultiple service is used by a client BACnet-user
+ * to modify the value of one or more specified properties of a BACnet object.
+ * This service potentially allows write access to any property of any object,
  * whether a BACnet-defined object or not.
- * Properties shall be modified by the WritePropertyMultiple service 
- * in the order specified in the 'List of Write Access Specifications' parameter, 
- * and execution of the service shall continue until all of the specified 
- * properties have been written to or a property is encountered that 
+ * Properties shall be modified by the WritePropertyMultiple service
+ * in the order specified in the 'List of Write Access Specifications' parameter,
+ * and execution of the service shall continue until all of the specified
+ * properties have been written to or a property is encountered that
  * for some reason cannot be modified as requested.
- * Some implementors may wish to restrict write access to certain properties 
- * of certain objects. In such cases, an attempt to modify a restricted property 
+ * Some implementors may wish to restrict write access to certain properties
+ * of certain objects. In such cases, an attempt to modify a restricted property
  * shall result in the return of an error of 'Error Class' PROPERTY and 'Error Code'
- * WRITE_ACCESS_DENIED. Note that these restricted properties may be accessible 
- * through the use of Virtual Terminal services or other means at the discretion 
+ * WRITE_ACCESS_DENIED. Note that these restricted properties may be accessible
+ * through the use of Virtual Terminal services or other means at the discretion
  * of the implementor.
 */
 #endif
diff --git a/bacnet-stack/src/wpm.c b/bacnet-stack/src/wpm.c
index a2c184f2..3e0fc7ce 100644
--- a/bacnet-stack/src/wpm.c
+++ b/bacnet-stack/src/wpm.c
@@ -1,6 +1,7 @@
 /**************************************************************************
 *
 * Copyright (C) 2011 Krzysztof Malorny <malornykrzysztof@gmail.com>
+* Contributions by ?????? ????? 2011 <nikola.jelic@euroicc.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
@@ -134,6 +135,82 @@ int wpm_decode_object_property(
     return len;
 }
 
+/* encode functions */
+int wpm_encode_apdu_init (uint8_t * apdu, uint8_t invoke_id)
+{
+    int apdu_len = 0;             /* total length of the apdu, return value */
+
+    if (apdu) {
+        apdu[0] = PDU_TYPE_CONFIRMED_SERVICE_REQUEST;
+        apdu[1] = encode_max_segs_max_apdu (0, MAX_APDU);
+        apdu[2] = invoke_id;
+        apdu[3] = SERVICE_CONFIRMED_WRITE_PROP_MULTIPLE;    /* service choice */
+        apdu_len = 4;
+    }
+
+    return apdu_len;
+
+}
+
+int wpm_encode_apdu_object_begin (
+    uint8_t * apdu,
+    BACNET_OBJECT_TYPE object_type,
+    uint32_t object_instance)
+{
+    int apdu_len = 0;             /* total length of the apdu, return value */
+
+    if (apdu) {
+        apdu_len = encode_context_object_id (
+            &apdu[0], 0, object_type, object_instance);
+        /* Tag 1: sequence of WriteAccessSpecification */
+        apdu_len += encode_opening_tag (&apdu[apdu_len], 1);
+    }
+
+    return apdu_len;
+}
+
+int wpm_encode_apdu_object_end (uint8_t * apdu)
+{
+    int apdu_len = 0;             /* total length of the apdu, return value */
+
+    if (apdu) {
+        apdu_len = encode_closing_tag (&apdu[0], 1);
+    }
+
+    return apdu_len;
+}
+
+int wpm_encode_apdu_object_property (
+    uint8_t * apdu,
+    BACNET_WRITE_PROPERTY_DATA * wpdata)
+{
+    int apdu_len = 0;             /* total length of the apdu, return value */
+    int len = 0;
+
+    if (apdu) {
+        apdu_len = encode_context_enumerated (&apdu[0], 0,
+            wpdata->object_property);
+        /* optional array index */
+        if (wpdata->array_index != BACNET_ARRAY_ALL) {
+            apdu_len +=
+                encode_context_unsigned (&apdu[apdu_len], 1,
+                wpdata->array_index);
+        }
+        apdu_len += encode_opening_tag (&apdu[apdu_len], 2);
+        for (len = 0; len < wpdata->application_data_len; len++) {
+            apdu[apdu_len] = wpdata->application_data[len];
+            apdu_len++;
+        }
+        apdu_len += encode_closing_tag (&apdu[apdu_len], 2);
+        if (wpdata->priority != BACNET_NO_PRIORITY) {
+            encode_context_unsigned (&apdu[apdu_len], 3,
+            wpdata->priority);
+        }
+    }
+
+    return apdu_len;
+}
+
 int wpm_ack_encode_apdu_init(
     uint8_t * apdu,
     uint8_t invoke_id)