diff --git a/Target/Source/plausibility.h b/Target/Source/plausibility.h
index c0077245..6755019f 100644
--- a/Target/Source/plausibility.h
+++ b/Target/Source/plausibility.h
@@ -474,7 +474,7 @@
 
 
 /****************************************************************************************
-*   S E E D / K E Y   S E C U R I T Y   C O N F I G U R A T I O N
+*   X C P   M O D U L E   C O N F I G U R A T I O N   C H E C K
 ****************************************************************************************/
 #ifndef BOOT_XCP_SEED_KEY_ENABLE
 #define BOOT_XCP_SEED_KEY_ENABLE        (0)
@@ -484,6 +484,14 @@
 #error "BOOT_XCP_SEED_KEY_ENABLE must be 0 or 1"
 #endif
 
+#ifndef BOOT_XCP_PACKET_RECEIVED_HOOK
+#define BOOT_XCP_PACKET_RECEIVED_HOOK   (0)
+#endif
+
+#if (BOOT_XCP_PACKET_RECEIVED_HOOK < 0) || (BOOT_XCP_PACKET_RECEIVED_HOOK > 1)
+#error "BOOT_XCP_PACKET_RECEIVED_HOOK must be 0 or 1"
+#endif
+
 
 #endif /* PLAUSIBILITY_H */
 /*********************************** end of plausibility.h *****************************/
diff --git a/Target/Source/xcp.c b/Target/Source/xcp.c
index 94e1e4f3..c26740a5 100644
--- a/Target/Source/xcp.c
+++ b/Target/Source/xcp.c
@@ -33,84 +33,6 @@
 
 
 #if (BOOT_COM_ENABLE > 0)
-/****************************************************************************************
-* Defines
-****************************************************************************************/
-/** \brief XCP protocol layer version number (16-bit). */
-#define XCP_VERSION_PROTOCOL_LAYER  (0x0100)
-
-/** \brief XCP transport layer version number (16-bit). */
-#define XCP_VERSION_TRANSPORT_LAYER (0x0100)
-
-/* XCP packet identifiers */
-/** \brief Command response packet identifier. */
-#define XCP_PID_RES                 (0xff)
-/** \brief Error packet identifier. */
-#define XCP_PID_ERR                 (0xfe)
-
-/* XCP error codes */
-/** \brief Cmd processor synchronization error code. */
-#define XCP_ERR_CMD_SYNCH           (0x00)
-/** \brief Command was not executed error code. */
-#define XCP_ERR_CMD_BUSY            (0x10)
-/** \brief Unknown or unsupported command error code. */
-#define XCP_ERR_CMD_UNKNOWN         (0x20)
-/** \brief Parameter out of range error code. */
-#define XCP_ERR_OUT_OF_RANGE        (0x22)
-/** \brief Protected error code. Seed/key required. */
-#define XCP_ERR_ACCESS_LOCKED       (0x25)
-/** \brief Cal page not valid error code. */
-#define XCP_ERR_PAGE_NOT_VALID      (0x26)
-/** \brief Sequence error code. */
-#define XCP_ERR_SEQUENCE            (0x29)
-/** \brief Generic error code. */
-#define XCP_ERR_GENERIC             (0x31)
-
-/* XCP command codes */
-/** \brief CONNECT command code. */
-#define XCP_CMD_CONNECT             (0xff)
-/** \brief DISCONNECT command code. */
-#define XCP_CMD_DISCONNECT          (0xfe)
-/** \brief GET_STATUS command code. */
-#define XCP_CMD_GET_STATUS          (0xfd)
-/** \brief SYNCH command code. */
-#define XCP_CMD_SYNCH               (0xfc)
-/** \brief GET_ID command code. */
-#define XCP_CMD_GET_ID              (0xfa)
-/** \brief GET_SEED command code. */
-#define XCP_CMD_GET_SEED            (0xf8)
-/** \brief UNLOCK command code. */
-#define XCP_CMD_UNLOCK              (0xf7)
-/** \brief SET_MTA command code. */
-#define XCP_CMD_SET_MTA             (0xf6)
-/** \brief UPLOAD command code. */
-#define XCP_CMD_UPLOAD              (0xf5)
-/** \brief SHORT_UPLOAD command code. */
-#define XCP_CMD_SHORT_UPLOAD        (0xf4)
-/** \brief BUILD_CHECKSUM command code. */
-#define XCP_CMD_BUILD_CHECKSUM      (0xf3)
-/** \brief DOWNLOAD command code. */
-#define XCP_CMD_DOWNLOAD            (0xf0)
-/** \brief DOWNLOAD_MAX command code. */
-#define XCP_CMD_DOWLOAD_MAX         (0xee)
-/** \brief SET_CALPAGE command code. */
-#define XCP_CMD_SET_CAL_PAGE        (0xeb)
-/** \brief GET_CALPAGE command code. */
-#define XCP_CMD_GET_CAL_PAGE        (0xea)
-/** \brief PROGRAM_START command code. */
-#define XCP_CMD_PROGRAM_START       (0xd2)
-/** \brief PROGRAM_CLEAR command code. */
-#define XCP_CMD_PROGRAM_CLEAR       (0xd1)
-/** \brief PROGRAM command code. */
-#define XCP_CMD_PROGRAM             (0xd0)
-/** \brief PROGRAM_RESET command code. */
-#define XCP_CMD_PROGRAM_RESET       (0xcf)
-/** \brief PROGRAM_PREPARE command code. */
-#define XCP_CMD_PROGRAM_PREPARE     (0xcc)
-/** \brief PROGRAM_MAX command code. */
-#define XCP_CMD_PROGRAM_MAX         (0xc9)
-
-
 /****************************************************************************************
 * Type definitions
 ****************************************************************************************/
@@ -181,22 +103,21 @@ static void XcpCmdProgramPrepare(blt_int8u *data);
 /****************************************************************************************
 * Hook functions
 ****************************************************************************************/
+#if (XCP_PACKET_RECEIVED_HOOK_EN == 1)
+extern blt_bool XcpPacketReceivedHook(blt_int8u *data);
+#endif
+
 #if (XCP_RES_PAGING_EN == 1)
 extern blt_int8u XcpCalSetPageHook(blt_int8u segment, blt_int8u page);
 extern blt_int8u XcpCalGetPageHook(blt_int8u segment);
 #endif
 
-#if (XCP_CONNECT_MODE_HOOK_EN == 1)
-extern blt_bool XcpConnectModeHook(blt_int8u mode);
-#endif
-
 #if (XCP_SEED_KEY_PROTECTION_EN == 1)
 extern blt_int8u XcpGetSeedHook(blt_int8u resource, blt_int8u *seed);
 extern blt_int8u XcpVerifyKeyHook(blt_int8u resource, blt_int8u *key, blt_int8u len);
 #endif
 
 
-
 /****************************************************************************************
 * External functions
 ****************************************************************************************/
@@ -277,6 +198,17 @@ void XcpPacketTransmitted(void)
 ****************************************************************************************/
 void XcpPacketReceived(blt_int8u *data)
 {
+#if (XCP_PACKET_RECEIVED_HOOK_EN == 1)
+  /* give the hook function a chance to process this packet. A return value of BLT_TRUE
+   * indicates that the hook function processed the packet and that no further processing
+   * is required.
+   */
+  if (XcpPacketReceivedHook(data) == BLT_TRUE)
+  {
+    /* packet processed by hook function so no need to continue. */
+    return;
+  }
+#endif
   /* was this a connect command? */
   if (data[0] == XCP_CMD_CONNECT)
   {
@@ -539,20 +471,6 @@ static void XcpCmdConnect(blt_int8u *data)
   }
 #endif
 
-#if (XCP_CONNECT_MODE_HOOK_EN == 1)
-  /* pass on the mode to a application specific hook function. This function can determine
-   * is the mode is supported or not. A return value of BLT_FALSE causes the CONNECT command
-   * to be ignored. Note that this mode could potentially be used to specify a node ID in a
-   * multi XCP slave system.
-   */
-  if (XcpConnectModeHook(data[1]) == BLT_FALSE)
-  {
-    /* set the response length to 0 to suppress it */
-    xcpInfo.ctoLen = 0;
-    return;
-  }
-#endif
-
   /* enable resource protection */
   XcpProtectResources();
 
diff --git a/Target/Source/xcp.h b/Target/Source/xcp.h
index fa073cbf..01e9c98c 100644
--- a/Target/Source/xcp.h
+++ b/Target/Source/xcp.h
@@ -99,10 +99,103 @@
 #define XCP_SEED_KEY_PROTECTION_EN     (0)
 #endif
 
+/** \brief Enable (=1) or disable the hook function that gets called each time an XCP
+ *         packet was received from the host.
+ *  \details A master-slave bootloader can be realized by using this hook-function. The
+ *           mode parameter in the XCP Connect command can be interpreted as a node ID.
+ *           When trying to connect to a slave, a gateway could be activated that passes
+ *           the packet on to the slave. When the response packet is received from the
+ *           slave, ComTransmitPacket() can be called to pass the response on to the
+ *           host. At the end of a firmware update procedure, the XCP Program Reset
+ *           command is called, which can be used to deactivate the gateway. If this
+ *           hook-function returns BLT_TRUE, the packet is no longer processed by the XCP
+ *           module. If it returns BLT_FALSE, then the packet is processed as usual by
+ *           the XCP module.
+ */
+#if (BOOT_XCP_PACKET_RECEIVED_HOOK > 0)
+#define XCP_PACKET_RECEIVED_HOOK_EN    (1)
+#else
+#define XCP_PACKET_RECEIVED_HOOK_EN    (0)
+#endif
+
 
 /****************************************************************************************
 * Defines
 ****************************************************************************************/
+/** \brief XCP protocol layer version number (16-bit). */
+#define XCP_VERSION_PROTOCOL_LAYER  (0x0100)
+
+/** \brief XCP transport layer version number (16-bit). */
+#define XCP_VERSION_TRANSPORT_LAYER (0x0100)
+
+/* XCP packet identifiers */
+/** \brief Command response packet identifier. */
+#define XCP_PID_RES                 (0xff)
+/** \brief Error packet identifier. */
+#define XCP_PID_ERR                 (0xfe)
+
+/* XCP error codes */
+/** \brief Cmd processor synchronization error code. */
+#define XCP_ERR_CMD_SYNCH           (0x00)
+/** \brief Command was not executed error code. */
+#define XCP_ERR_CMD_BUSY            (0x10)
+/** \brief Unknown or unsupported command error code. */
+#define XCP_ERR_CMD_UNKNOWN         (0x20)
+/** \brief Parameter out of range error code. */
+#define XCP_ERR_OUT_OF_RANGE        (0x22)
+/** \brief Protected error code. Seed/key required. */
+#define XCP_ERR_ACCESS_LOCKED       (0x25)
+/** \brief Cal page not valid error code. */
+#define XCP_ERR_PAGE_NOT_VALID      (0x26)
+/** \brief Sequence error code. */
+#define XCP_ERR_SEQUENCE            (0x29)
+/** \brief Generic error code. */
+#define XCP_ERR_GENERIC             (0x31)
+
+/* XCP command codes */
+/** \brief CONNECT command code. */
+#define XCP_CMD_CONNECT             (0xff)
+/** \brief DISCONNECT command code. */
+#define XCP_CMD_DISCONNECT          (0xfe)
+/** \brief GET_STATUS command code. */
+#define XCP_CMD_GET_STATUS          (0xfd)
+/** \brief SYNCH command code. */
+#define XCP_CMD_SYNCH               (0xfc)
+/** \brief GET_ID command code. */
+#define XCP_CMD_GET_ID              (0xfa)
+/** \brief GET_SEED command code. */
+#define XCP_CMD_GET_SEED            (0xf8)
+/** \brief UNLOCK command code. */
+#define XCP_CMD_UNLOCK              (0xf7)
+/** \brief SET_MTA command code. */
+#define XCP_CMD_SET_MTA             (0xf6)
+/** \brief UPLOAD command code. */
+#define XCP_CMD_UPLOAD              (0xf5)
+/** \brief SHORT_UPLOAD command code. */
+#define XCP_CMD_SHORT_UPLOAD        (0xf4)
+/** \brief BUILD_CHECKSUM command code. */
+#define XCP_CMD_BUILD_CHECKSUM      (0xf3)
+/** \brief DOWNLOAD command code. */
+#define XCP_CMD_DOWNLOAD            (0xf0)
+/** \brief DOWNLOAD_MAX command code. */
+#define XCP_CMD_DOWLOAD_MAX         (0xee)
+/** \brief SET_CALPAGE command code. */
+#define XCP_CMD_SET_CAL_PAGE        (0xeb)
+/** \brief GET_CALPAGE command code. */
+#define XCP_CMD_GET_CAL_PAGE        (0xea)
+/** \brief PROGRAM_START command code. */
+#define XCP_CMD_PROGRAM_START       (0xd2)
+/** \brief PROGRAM_CLEAR command code. */
+#define XCP_CMD_PROGRAM_CLEAR       (0xd1)
+/** \brief PROGRAM command code. */
+#define XCP_CMD_PROGRAM             (0xd0)
+/** \brief PROGRAM_RESET command code. */
+#define XCP_CMD_PROGRAM_RESET       (0xcf)
+/** \brief PROGRAM_PREPARE command code. */
+#define XCP_CMD_PROGRAM_PREPARE     (0xcc)
+/** \brief PROGRAM_MAX command code. */
+#define XCP_CMD_PROGRAM_MAX         (0xc9)
+
 /* xcp supported resources */
 /** \brief ProGraMming resource. */
 #define XCP_RES_PGM            (0x10)
@@ -227,6 +320,14 @@ void     XcpPacketReceived(blt_int8u *data);
 #endif
 
 
+#ifndef XCP_PACKET_RECEIVED_HOOK_EN
+#error  "XCP.H, Configuration macro XCP_PACKET_RECEIVED_HOOK_EN is missing."
+#endif
+
+#if     (XCP_PACKET_RECEIVED_HOOK_EN < 0) || (XCP_PACKET_RECEIVED_HOOK_EN > 1)
+#error  "XCP.H, XCP_PACKET_RECEIVED_HOOK_EN must be 0 or 1."
+#endif
+
 #endif /* BOOT_COM_ENABLE > 0 */
 #endif /* XCP_H */
 /******************************** end of xcp.h *~~~~~***********************************/