diff --git a/bin/mbus-serial-request-data-multi-reply.c b/bin/mbus-serial-request-data-multi-reply.c
old mode 100644
new mode 100755
index 36831bc..0f1fb7a
--- a/bin/mbus-serial-request-data-multi-reply.c
+++ b/bin/mbus-serial-request-data-multi-reply.c
@@ -73,13 +73,19 @@ main(int argc, char **argv)
         mbus_register_recv_event(&mbus_dump_recv_event);
     }
  
-    if ((handle = mbus_connect_serial(device)) == NULL)
+    if ((handle = mbus_context_serial(device)) == NULL)
     {
-        fprintf(stderr, "Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
         return 1;
     }
 
-    if (mbus_serial_set_baudrate(handle->m_serial_handle, baudrate) == -1)
+    if (!mbus_connect(handle))
+    {
+        printf("Failed to setup connection to M-bus gateway\n");
+        return 1;
+    }
+
+    if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
         printf("Failed to set baud rate.\n");
         return 1;
@@ -110,7 +116,7 @@ main(int argc, char **argv)
         return 1;
     }
     
-    while (mbus_recv_frame(handle, &reply) != -1);
+    mbus_purge_frames(handle);
     
     //
     // resend SND_NKE, maybe the first get lost
@@ -129,7 +135,7 @@ main(int argc, char **argv)
         return 1;
     }
 
-    while (mbus_recv_frame(handle, &reply) != -1);
+    mbus_purge_frames(handle);
 
     if (strlen(addr_str) == 16)
     {
@@ -193,6 +199,7 @@ main(int argc, char **argv)
     free(xml_result);
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-serial-request-data.c b/bin/mbus-serial-request-data.c
old mode 100644
new mode 100755
index 219a49d..46526a7
--- a/bin/mbus-serial-request-data.c
+++ b/bin/mbus-serial-request-data.c
@@ -70,13 +70,19 @@ main(int argc, char **argv)
         mbus_register_recv_event(&mbus_dump_recv_event);
     }
  
-    if ((handle = mbus_connect_serial(device)) == NULL)
+    if ((handle = mbus_context_serial(device)) == NULL)
     {
-        fprintf(stderr, "Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
         return 1;
     }
 
-    if (mbus_serial_set_baudrate(handle->m_serial_handle, baudrate) == -1)
+    if (mbus_connect(handle) == -1)
+    {
+        printf("Failed to setup connection to M-bus gateway\n");
+        return 1;
+    }
+
+    if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
         printf("Failed to set baud rate.\n");
         return 1;
@@ -162,6 +168,7 @@ main(int argc, char **argv)
     }
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-serial-scan-secondary.c b/bin/mbus-serial-scan-secondary.c
old mode 100644
new mode 100755
index 960c066..b395c63
--- a/bin/mbus-serial-scan-secondary.c
+++ b/bin/mbus-serial-scan-secondary.c
@@ -102,13 +102,19 @@ main(int argc, char **argv)
         return 1;
     }
 
-    if ((handle = mbus_connect_serial(device)) == NULL)
+    if ((handle = mbus_context_serial(device)) == NULL)
     {
-        fprintf(stderr, "Failed to setup connection to M-bus gateway: %s\n", mbus_error_str());
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
         return 1;
     }
 
-    if (mbus_serial_set_baudrate(handle->m_serial_handle, baudrate) == -1)
+    if (!mbus_connect(handle))
+    {
+        printf("Failed to setup connection to M-bus gateway\n");
+        return 1;
+    }
+
+    if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
         fprintf(stderr, "Failed to set baud rate.\n");
         return 1;
@@ -153,7 +159,7 @@ main(int argc, char **argv)
     mbus_scan_2nd_address_range(handle, 0, addr_mask);
 
     mbus_disconnect(handle);
-
+    mbus_context_free(handle);
     //printf("Summary: Tried %ld address masks and found %d devices.\n", probe_count, match_count);
 
     free(addr_mask);
diff --git a/bin/mbus-serial-scan.c b/bin/mbus-serial-scan.c
old mode 100644
new mode 100755
index 3d7c8bf..1d2d0f8
--- a/bin/mbus-serial-scan.c
+++ b/bin/mbus-serial-scan.c
@@ -62,13 +62,19 @@ main(int argc, char **argv)
         mbus_register_recv_event(&mbus_dump_recv_event);
     }
     
-    if ((handle = mbus_connect_serial(device)) == NULL)
+    if ((handle = mbus_context_serial(device)) == NULL)
+    {
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
     {
         printf("Failed to setup connection to M-bus gateway\n");
         return 1;
     }
 
-    if (mbus_serial_set_baudrate(handle->m_serial_handle, baudrate) == -1)
+    if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
         printf("Failed to set baud rate.\n");
         return 1;
@@ -97,7 +103,7 @@ main(int argc, char **argv)
         
         ret = mbus_recv_frame(handle, &reply);
 
-        if (ret == -1)
+        if (ret == -3)
         {
             continue;
         }
@@ -108,22 +114,15 @@ main(int argc, char **argv)
         if (ret == -2)
         {
             /* check for more data (collision) */
-            while (mbus_recv_frame(handle, &reply) != -1);
-            
+            mbus_purge_frames(handle);
             printf("Collision at address %d\n", address);
-            
             continue;
         } 
 
         if (mbus_frame_type(&reply) == MBUS_FRAME_TYPE_ACK)
         {
             /* check for more data (collision) */
-            while (mbus_recv_frame(handle, &reply) != -1)
-            {
-                ret = -2;
-            }
-    
-            if (ret == -2)
+            if (mbus_purge_frames(handle))
             {
                 printf("Collision at address %d\n", address);
                 
@@ -135,6 +134,7 @@ main(int argc, char **argv)
     }
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-serial-select-secondary.c b/bin/mbus-serial-select-secondary.c
old mode 100644
new mode 100755
index a5b7067..624a384
--- a/bin/mbus-serial-select-secondary.c
+++ b/bin/mbus-serial-select-secondary.c
@@ -53,13 +53,19 @@ main(int argc, char **argv)
         return 1;
     }
 
-    if ((handle = mbus_connect_serial(device)) == NULL)
+    if ((handle = mbus_context_serial(device)) == NULL)
     {
-        printf("Failed to setup connection to M-bus device: %s\n", mbus_error_str());
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
         return 1;
     }
 
-    if (mbus_serial_set_baudrate(handle->m_serial_handle, baudrate) == -1)
+    if (mbus_connect(handle) == -1)
+    {
+        printf("Failed to setup connection to M-bus gateway\n");
+        return 1;
+    }
+
+    if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
         printf("Failed to set baud rate.\n");
         return 1;
@@ -73,7 +79,7 @@ main(int argc, char **argv)
 
     ret = mbus_recv_frame(handle, &reply);
 
-    if (ret == -1)
+    if (ret == -3)
     {
         printf("No reply from device with secondary address %s: %s\n", argv[2], mbus_error_str());
         return 1;
@@ -93,7 +99,7 @@ main(int argc, char **argv)
             return 1;
         }
 
-        if (mbus_recv_frame(handle, &reply) == -1)
+        if (mbus_recv_frame(handle, &reply) != 0)
         {
             printf("Failed to recieve reply from selected secondary device: %s\n", mbus_error_str());
             return 1;
@@ -113,6 +119,7 @@ main(int argc, char **argv)
  
     free(addr);
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-serial-switch-baudrate.c b/bin/mbus-serial-switch-baudrate.c
old mode 100644
new mode 100755
index 4a0d91e..e67b98c
--- a/bin/mbus-serial-switch-baudrate.c
+++ b/bin/mbus-serial-switch-baudrate.c
@@ -52,13 +52,19 @@ main(int argc, char **argv)
         return 0;
     }
 
-    if ((handle = mbus_connect_serial(device)) == NULL)
+    if ((handle = mbus_context_serial(device)) == NULL)
     {
-        printf("Failed to setup connection to M-bus device: %s\n", mbus_error_str());
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
+    {
+        printf("Failed to setup connection to M-bus gateway\n");
         return 1;
     }
     
-    if (mbus_serial_set_baudrate(handle->m_serial_handle, source_baudrate) == -1)
+    if (mbus_serial_set_baudrate(handle, source_baudrate) == -1)
     {
         printf("Failed to set baud rate.\n");
         return 1;
@@ -72,7 +78,7 @@ main(int argc, char **argv)
 
     ret = mbus_recv_frame(handle, &reply);  
     
-    if (ret == -1)
+    if (ret == -3)
     {
         printf("No reply from device\n");
         return 1;
@@ -88,6 +94,7 @@ main(int argc, char **argv)
     }
     
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-tcp-request-data-multi-reply.c b/bin/mbus-tcp-request-data-multi-reply.c
old mode 100644
new mode 100755
index 7c165c0..7d421f0
--- a/bin/mbus-tcp-request-data-multi-reply.c
+++ b/bin/mbus-tcp-request-data-multi-reply.c
@@ -62,7 +62,13 @@ main(int argc, char **argv)
         mbus_register_recv_event(&mbus_dump_recv_event);
     }
     
-    if ((handle = mbus_connect_tcp(host, port)) == NULL)
+    if ((handle = mbus_context_tcp(host, port)) == NULL)
+    {
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
     {
         fprintf(stderr, "Failed to setup connection to M-bus gateway\n");
         return 1;
@@ -157,6 +163,7 @@ main(int argc, char **argv)
     free(xml_result);
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-tcp-request-data.c b/bin/mbus-tcp-request-data.c
old mode 100644
new mode 100755
index fce7b7b..1ed504f
--- a/bin/mbus-tcp-request-data.c
+++ b/bin/mbus-tcp-request-data.c
@@ -62,7 +62,13 @@ main(int argc, char **argv)
         mbus_register_recv_event(&mbus_dump_recv_event);
     }
     
-    if ((handle = mbus_connect_tcp(host, port)) == NULL)
+    if ((handle = mbus_context_tcp(host, port)) == NULL)
+    {
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
     {
         fprintf(stderr, "Failed to setup connection to M-bus gateway\n");
         return 1;
@@ -113,9 +119,9 @@ main(int argc, char **argv)
 
     if (mbus_recv_frame(handle, &reply) != 0)
     {
-        fprintf(stderr, "Failed to receive M-Bus response frame.\n");
+        fprintf(stderr, "Failed to receive M-Bus response frame: %s\n", mbus_error_str());
         return 1;
-    }    
+    }
 
     //
     // parse data and print in XML format
@@ -147,6 +153,7 @@ main(int argc, char **argv)
     }
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-tcp-scan-secondary.c b/bin/mbus-tcp-scan-secondary.c
old mode 100644
new mode 100755
index 6a97484..bd1c12f
--- a/bin/mbus-tcp-scan-secondary.c
+++ b/bin/mbus-tcp-scan-secondary.c
@@ -57,9 +57,15 @@ main(int argc, char **argv)
         return 1;
     }
 
-    if ((handle = mbus_connect_tcp(host, port)) == NULL)
+    if ((handle = mbus_context_tcp(host, port)) == NULL)
     {
-        fprintf(stderr, "Failed to setup connection to M-bus gateway: %s\n", mbus_error_str());
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
+    {
+        fprintf(stderr, "Failed to setup connection to M-bus gateway\n");
         return 1;
     }
     
@@ -103,6 +109,7 @@ main(int argc, char **argv)
     mbus_scan_2nd_address_range(handle, 0, addr_mask);
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
 
     //printf("Summary: Tried %ld address masks and found %d devices.\n", probe_count, match_count);
 
diff --git a/bin/mbus-tcp-scan.c b/bin/mbus-tcp-scan.c
old mode 100644
new mode 100755
index d6dcee4..2776018
--- a/bin/mbus-tcp-scan.c
+++ b/bin/mbus-tcp-scan.c
@@ -17,7 +17,6 @@
 #include <stdio.h>
 #include <mbus/mbus.h>
 
-
 //------------------------------------------------------------------------------
 // Execution starts here:
 //------------------------------------------------------------------------------
@@ -52,7 +51,13 @@ main(int argc, char **argv)
         mbus_register_recv_event(&mbus_dump_recv_event);
     }
      
-    if ((handle = mbus_connect_tcp(host, port)) == NULL)
+    if ((handle = mbus_context_tcp(host, port)) == NULL)
+    {
+        printf("Scan failed: Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
     {
         printf("Scan failed: Could not setup connection to M-bus gateway: %s\n",  mbus_error_str());
         return 1;
@@ -81,7 +86,7 @@ main(int argc, char **argv)
         
         ret = mbus_recv_frame(handle, &reply);
 
-        if (ret == -1)
+        if (ret == -3)
         {
             continue;
         }
@@ -92,33 +97,26 @@ main(int argc, char **argv)
         if (ret == -2)
         {
             /* check for more data (collision) */
-            while (mbus_recv_frame(handle, &reply) != -1);
-            
+            mbus_purge_frames(handle);
             printf("Collision at address %d\n", address);
-            
             continue;
         } 
 
         if (mbus_frame_type(&reply) == MBUS_FRAME_TYPE_ACK)
         {
             /* check for more data (collision) */
-            while (mbus_recv_frame(handle, &reply) != -1)
-            {
-                ret = -2;
-            }
-    
-            if (ret == -2)
+            if (mbus_purge_frames(handle))
             {
                 printf("Collision at address %d\n", address);
-                
                 continue;
             }
-                
+
             printf("Found a M-Bus device at address %d\n", address);
         }
     }
 
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/bin/mbus-tcp-select-secondary.c b/bin/mbus-tcp-select-secondary.c
old mode 100644
new mode 100755
index 712abe2..5268650
--- a/bin/mbus-tcp-select-secondary.c
+++ b/bin/mbus-tcp-select-secondary.c
@@ -45,9 +45,15 @@ main(int argc, char **argv)
         return 1;
     }
 
-    if ((handle = mbus_connect_tcp(host, port)) == NULL)
+    if ((handle = mbus_context_tcp(host, port)) == NULL)
     {
-        printf("Failed to setup connection to M-bus gateway: %s\n", mbus_error_str());
+        fprintf(stderr, "Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        return 1;
+    }
+
+    if (mbus_connect(handle) == -1)
+    {
+        fprintf(stderr, "Failed to setup connection to M-bus gateway\n");
         return 1;
     }
 
@@ -59,7 +65,7 @@ main(int argc, char **argv)
 
     ret = mbus_recv_frame(handle, &reply);
 
-    if (ret == -1)
+    if (ret == -3)
     {
         printf("No reply from device with secondary address %s: %s\n", argv[3], mbus_error_str());
         return 1;
@@ -79,7 +85,7 @@ main(int argc, char **argv)
             return 1;
         }
 
-        if (mbus_recv_frame(handle, &reply) == -1)
+        if (mbus_recv_frame(handle, &reply) != 0)
         {
             printf("Failed to recieve reply from selected secondary device: %s\n", mbus_error_str());
             return 1;
@@ -99,6 +105,7 @@ main(int argc, char **argv)
  
     free(addr);
     mbus_disconnect(handle);
+    mbus_context_free(handle);
     return 0;
 }
 
diff --git a/mbus/mbus-protocol-aux.c b/mbus/mbus-protocol-aux.c
old mode 100644
new mode 100755
index bba0cbc..cb11257
--- a/mbus/mbus-protocol-aux.c
+++ b/mbus/mbus-protocol-aux.c
@@ -12,6 +12,8 @@
 //------------------------------------------------------------------------------
 
 #include "mbus-protocol-aux.h"
+#include "mbus-serial.h"
+#include "mbus-tcp.h"
 
 #include <stdio.h>
 #include <string.h>
@@ -1308,74 +1310,120 @@ mbus_frame_data_xml_normalized(mbus_frame_data *data)
 }
 
 mbus_handle *
-mbus_connect_serial(const char * device)
+mbus_context_serial(const char *device)
 {
-    mbus_serial_handle * serial_handle;
-    if ((serial_handle = mbus_serial_connect((char*)device)) == NULL)
-    {
-        MBUS_ERROR("%s: Failed to setup serial connection to M-bus gateway on %s.\n",
-                   __PRETTY_FUNCTION__, 
-                   device);
-        return NULL;
-    }
+    mbus_handle *handle;
+    mbus_serial_data *serial_data;
+    char error_str[128];
 
-    mbus_handle * handle;
-    if ((handle = (mbus_handle * ) malloc(sizeof(mbus_handle))) == NULL)
+    if ((handle = (mbus_handle *) malloc(sizeof(mbus_handle))) == NULL)
     {
         MBUS_ERROR("%s: Failed to allocate handle.\n", __PRETTY_FUNCTION__);
         return NULL;
     }
+
+    if ((serial_data = (mbus_serial_data *)malloc(sizeof(mbus_serial_data))) == NULL)
+    {
+        snprintf(error_str, sizeof(error_str), "%s: failed to allocate memory for handle\n", __PRETTY_FUNCTION__);
+        mbus_error_str_set(error_str);
+        free(handle);
+        return NULL;
+    }
+
     handle->is_serial = 1;
-    handle->m_serial_handle = serial_handle;
+    handle->auxdata = serial_data;
+    handle->open = mbus_serial_connect;
+    handle->close = mbus_serial_disconnect;
+    handle->recv = mbus_serial_recv_frame;
+    handle->send = mbus_serial_send_frame;
+    handle->free_auxdata = mbus_serial_data_free;
+
+    if ((serial_data->device = strdup(device)) == NULL)
+    {
+        snprintf(error_str, sizeof(error_str), "%s: failed to allocate memory for device\n", __PRETTY_FUNCTION__);
+        mbus_error_str_set(error_str);
+        free(serial_data);
+        free(handle);
+        return NULL;
+    }
+
     return handle;
 }
 
-
 mbus_handle *
-mbus_connect_tcp(const char * host, int port)
+mbus_context_tcp(const char *host, int port)
 {
-    mbus_tcp_handle * tcp_handle;
-    if ((tcp_handle = mbus_tcp_connect((char*)host, port)) == NULL)
-    {
-        MBUS_ERROR("%s: Failed to setup tcp connection to M-bus gateway on %s, port %d.\n", 
-                   __PRETTY_FUNCTION__,
-                   host,
-                   port);
-        return NULL;
-    }
+    mbus_handle *handle;
+    mbus_tcp_data *tcp_data;
+    char error_str[128];
 
-    mbus_handle * handle;
-    if ((handle = (mbus_handle * ) malloc(sizeof(mbus_handle))) == NULL)
+    if ((handle = (mbus_handle *) malloc(sizeof(mbus_handle))) == NULL)
     {
         MBUS_ERROR("%s: Failed to allocate handle.\n", __PRETTY_FUNCTION__);
         return NULL;
     }
+
+    if ((tcp_data = (mbus_tcp_data *)malloc(sizeof(mbus_tcp_data))) == NULL)
+    {
+        snprintf(error_str, sizeof(error_str), "%s: failed to allocate memory for handle\n", __PRETTY_FUNCTION__);
+        mbus_error_str_set(error_str);
+        free(handle);
+        return NULL;
+    }
+
     handle->is_serial = 0;
-    handle->m_tcp_handle = tcp_handle;
+    handle->auxdata = tcp_data;
+    handle->open = mbus_tcp_connect;
+    handle->close = mbus_tcp_disconnect;
+    handle->recv = mbus_tcp_recv_frame;
+    handle->send = mbus_tcp_send_frame;
+    handle->free_auxdata = mbus_tcp_data_free;
+
+    tcp_data->port = port;
+    if ((tcp_data->host = strdup(host)) == NULL)
+    {
+        snprintf(error_str, sizeof(error_str), "%s: failed to allocate memory for host\n", __PRETTY_FUNCTION__);
+        mbus_error_str_set(error_str);
+        free(tcp_data);
+        free(handle);
+        return NULL;
+    }
+
     return handle;
 }
 
+void
+mbus_context_free(mbus_handle * handle)
+{
+    if (handle)
+    {
+        handle->free_auxdata(handle);
+        free(handle);
+    }
+}
+
+int
+mbus_connect(mbus_handle * handle)
+{
+    if (handle == NULL)
+    {
+        MBUS_ERROR("%s: Invalid M-Bus handle for disconnect.\n", __PRETTY_FUNCTION__);
+        return -1;
+    }
+
+    return handle->open(handle);
+}
+
 int
 mbus_disconnect(mbus_handle * handle)
 {
     if (handle == NULL)
     {
         MBUS_ERROR("%s: Invalid M-Bus handle for disconnect.\n", __PRETTY_FUNCTION__);
-        return 0;
+        return -1;
     }
 
-    if (handle->is_serial)
-    {
-        mbus_serial_disconnect(handle->m_serial_handle);
-        handle->m_serial_handle = NULL;
-    }
-    else
-    {
-        mbus_tcp_disconnect(handle->m_tcp_handle);
-        handle->m_tcp_handle = NULL;
-    }
-    free(handle);
-    return 0;
+    return handle->close(handle);
 }
 
 int
@@ -1386,24 +1434,17 @@ mbus_recv_frame(mbus_handle * handle, mbus_frame *frame)
     if (handle == NULL)
     {
         MBUS_ERROR("%s: Invalid M-Bus handle for receive.\n", __PRETTY_FUNCTION__);
-        return 0;
+        return -1;
     }
 
     if (frame == NULL)
     {
         MBUS_ERROR("%s: Invalid frame.\n", __PRETTY_FUNCTION__);
-        return 0;
+        return -1;
     }
 
-    if (handle->is_serial)
-    {
-        result = mbus_serial_recv_frame(handle->m_serial_handle, frame);    
-    }
-    else
-    {
-        result = mbus_tcp_recv_frame(handle->m_tcp_handle, frame);
-    }
-    
+    result = handle->recv(handle, frame);
+
     if (frame != NULL)
     {
         /* set timestamp to receive time */
@@ -1413,6 +1454,24 @@ mbus_recv_frame(mbus_handle * handle, mbus_frame *frame)
     return result;
 }
 
+int mbus_purge_frames(mbus_handle *handle)
+{
+    int err, received;
+    mbus_frame reply;
+
+    received = 0;
+    while (1)
+    {
+        err = mbus_recv_frame(handle, &reply);
+        if (err != -2 && err != 0)
+            break;
+
+        received = 1;
+    }
+
+    return received;
+}
+
 int
 mbus_send_frame(mbus_handle * handle, mbus_frame *frame)
 {
@@ -1422,15 +1481,7 @@ mbus_send_frame(mbus_handle * handle, mbus_frame *frame)
         return 0;
     }
 
-    if (handle->is_serial)
-    {
-        return mbus_serial_send_frame(handle->m_serial_handle, frame);
-    }
-    else
-    {
-        return mbus_tcp_send_frame(handle->m_tcp_handle, frame);
-    }
-    return 0;
+    return handle->send(handle, frame);
 }
 
 //------------------------------------------------------------------------------
@@ -1751,7 +1802,7 @@ mbus_select_secondary_address(mbus_handle * handle, const char *mask)
 
     ret = mbus_recv_frame(handle, &reply);
 
-    if (ret == -1)
+    if (ret == -3)
     {
         return MBUS_PROBE_NOTHING;
     }    
@@ -1759,20 +1810,14 @@ mbus_select_secondary_address(mbus_handle * handle, const char *mask)
     if (ret == -2)
     {
         /* check for more data (collision) */
-        while (mbus_recv_frame(handle, &reply) != -1);
-
+        mbus_purge_frames(handle);
         return MBUS_PROBE_COLLISION;
     }
 
     if (mbus_frame_type(&reply) == MBUS_FRAME_TYPE_ACK)
     {
         /* check for more data (collision) */
-        while (mbus_recv_frame(handle, &reply) != -1)
-        {
-            ret = -2;
-        }
-
-        if (ret == -2)
+        if (mbus_purge_frames(handle))
         {
             return MBUS_PROBE_COLLISION;
         }
@@ -1817,7 +1862,7 @@ mbus_probe_secondary_address(mbus_handle * handle, const char *mask, char *match
 
         ret = mbus_recv_frame(handle, &reply);
 
-        if (ret == -1)
+        if (ret == -3)
         {
             return MBUS_PROBE_NOTHING;
         }
diff --git a/mbus/mbus-protocol-aux.h b/mbus/mbus-protocol-aux.h
old mode 100644
new mode 100755
index 39cc454..71eeecd
--- a/mbus/mbus-protocol-aux.h
+++ b/mbus/mbus-protocol-aux.h
@@ -20,9 +20,11 @@
  * the data processing.
  * Typical use might be (in oversimplified "pseudocode"):
  * \verbatim
- * mbus_handle = mbus_connect_serial(device);
+ * mbus_handle = mbus_context_serial(device);
  *   or
- * mbus_handle = mbus_connect_tcp(host, port);
+ * mbus_handle = mbus_context_tcp(host, port);
+ *
+ * mbus_connect(mbus_handle);
  *
  *  ...
  *
@@ -45,6 +47,7 @@
  *  ...
  *
  * mbus_disconnect(mbus_handle);
+ * mbus_context_free(mbus_handle);
  * \endverbatim
  *
  * Note that the quantity values are partially "normalized". For example energy
@@ -60,28 +63,28 @@
 #ifndef __MBUS_PROTOCOL_AUX_H__
 #define __MBUS_PROTOCOL_AUX_H__
 
-#include <mbus/mbus.h>
-#include <mbus/mbus-protocol.h>
-#include <mbus/mbus-serial.h>
-#include <mbus/mbus-tcp.h>
+#include "mbus-protocol.h"
 
 #define MBUS_PROBE_NOTHING   0
 #define MBUS_PROBE_SINGLE    1
 #define MBUS_PROBE_COLLISION 2
 #define MBUS_PROBE_ERROR     -1
 
-
 /**
  * Unified MBus handle type encapsulating either Serial or TCP gateway.
  */
-typedef struct _mbus_handle {
-    char is_serial;                           /**< _handle type (non zero for serial) */
-    union {
-        mbus_tcp_handle    * m_tcp_handle;    /**< TCP gateway handle */
-        mbus_serial_handle * m_serial_handle; /**< Serial gateway handle */
-    };
-} mbus_handle;
+struct _mbus_handle {
+    int fd;
+    char is_serial; /**< _handle type (non zero for serial) */
+    int (*open) (struct _mbus_handle *handle);
+    int (*close) (struct _mbus_handle *handle);
+    int (*send) (struct _mbus_handle *handle, mbus_frame *frame);
+    int (*recv) (struct _mbus_handle *handle, mbus_frame *frame);
+    void (*free_auxdata) (struct _mbus_handle *handle);
+    void *auxdata;
+};
 
+typedef struct _mbus_handle mbus_handle;
 
 /**
  * MBus slave address type (primary/secodary address)
@@ -141,25 +144,42 @@ void mbus_register_scan_progress(void (*event)(mbus_handle * handle, const char
 void mbus_register_found_event(void (*event)(mbus_handle * handle, mbus_frame *frame));
 
 /** 
- * Connects to serial gateway and initializes MBus handle
+ * Allocate and initialize M-Bus serial context.
  * 
  * @param device Serial device (like /dev/ttyUSB0 or /dev/ttyS0)
  * 
  * @return Initialized "unified" handler when successful, NULL otherwise;
  */
-mbus_handle * mbus_connect_serial(const char * device);
+mbus_handle * mbus_context_serial(const char *device);
 
 /** 
- * Connects to TCP gateway and initializes MBus handle
+ * Allocate and initialize M-Bus TCP context.
  * 
  * @param host Gateway host
  * @param port Gateway port
  * 
  * @return Initialized "unified" handler when successful, NULL otherwise;
  */
-mbus_handle * mbus_connect_tcp(const char *host, int port);
+mbus_handle * mbus_context_tcp(const char *host, int port);
 
 /** 
+ * Deallocate memory used by M-Bus context.
+ *
+ * @param handle Initialized handle
+ *
+ */
+void mbus_context_free(mbus_handle * handle);
+
+/**
+ * Connect to serial bus or TCP gateway depending on context.
+ *
+ * @param handle Initialized handle
+ *
+ * @return Zero when successful.
+ */
+int mbus_connect(mbus_handle * handle);
+
+/**
  * Disconnects the "unified" handle.
  * 
  * @param handle Initialized handle
@@ -179,6 +199,15 @@ int mbus_disconnect(mbus_handle * handle);
 int mbus_recv_frame(mbus_handle * handle, mbus_frame *frame);
 
 /** 
+ * Used for handling collisions. Blocks as long as receiving frames or corrupted data.
+ *
+ * @param handle Initialized handle
+ *
+ * @return Zero when nothing received, one otherwise.
+ */
+int mbus_purge_frames(mbus_handle * handle);
+
+/**
  * Sends frame using "unified" handle
  * 
  * @param handle Initialized handle
diff --git a/mbus/mbus-protocol.c b/mbus/mbus-protocol.c
old mode 100644
new mode 100755
index 45df1be..e11dfe9
--- a/mbus/mbus-protocol.c
+++ b/mbus/mbus-protocol.c
@@ -13,7 +13,7 @@
 #include <stdio.h>
 #include <string.h>
 
-#include <mbus/mbus-protocol.h>
+#include "mbus-protocol.h"
 
 static int parse_debug = 0, debug = 0;
 static char error_str[512];
diff --git a/mbus/mbus-protocol.h b/mbus/mbus-protocol.h
old mode 100644
new mode 100755
diff --git a/mbus/mbus-serial.c b/mbus/mbus-serial.c
old mode 100644
new mode 100755
index 7a1aa28..d28e7eb
--- a/mbus/mbus-serial.c
+++ b/mbus/mbus-serial.c
@@ -20,49 +20,48 @@
 #include <errno.h>
 #include <string.h>
 
-#include <mbus/mbus.h>
-#include <mbus/mbus-serial.h>
+#include "mbus-serial.h"
+#include "mbus-protocol-aux.h"
+#include "mbus-protocol.h"
 
 #define PACKET_BUFF_SIZE 2048
 
 //------------------------------------------------------------------------------
 /// Set up a serial connection handle.
 //------------------------------------------------------------------------------
-mbus_serial_handle *
-mbus_serial_connect(char *device)
+int
+mbus_serial_connect(mbus_handle *handle)
 {
-    mbus_serial_handle *handle;
+    mbus_serial_data *serial_data;
+    const char *device;
+    struct termios *term;
 
-    if (device == NULL)
-    {
-        return NULL;
-    }
+    if (handle == NULL)
+        return -1;
 
-    if ((handle = (mbus_serial_handle *)malloc(sizeof(mbus_serial_handle))) == NULL)
-    {
-        fprintf(stderr, "%s: failed to allocate memory for handle\n", __PRETTY_FUNCTION__);
-        return NULL;
-    }
-
-    handle->device = device; // strdup?
+    serial_data = (mbus_serial_data *) handle->auxdata;
+    if (serial_data == NULL || serial_data->device == NULL)
+        return -1;
 
+    device = serial_data->device;
+    term = &(serial_data->t);
     //
     // create the SERIAL connection
     //
 
     // Use blocking read and handle it by serial port VMIN/VTIME setting
-    if ((handle->fd = open(handle->device, O_RDWR | O_NOCTTY)) < 0)
+    if ((handle->fd = open(device, O_RDWR | O_NOCTTY)) < 0)
     {
         fprintf(stderr, "%s: failed to open tty.", __PRETTY_FUNCTION__);
-        return NULL;
+        return -1;
     }
 
-    memset(&(handle->t), 0, sizeof(handle->t));
-    handle->t.c_cflag |= (CS8|CREAD|CLOCAL);
-    handle->t.c_cflag |= PARENB;
+    memset(term, 0, sizeof(*term));
+    term->c_cflag |= (CS8|CREAD|CLOCAL);
+    term->c_cflag |= PARENB;
 
     // No received data still OK
-    handle->t.c_cc[VMIN]  = 0;
+    term->c_cc[VMIN]  = 0;
 
     // Wait at most 0.2 sec.Note that it starts after first received byte!!
     // I.e. if CMIN>0 and there are no data we would still wait forever...
@@ -71,58 +70,60 @@ mbus_serial_connect(char *device)
     // The time structure of various link layer communication types is described in EN60870-5-1. The answer time
     // between the end of a master send telegram and the beginning of the response telegram of the slave shall be
     // between 11 bit times and (330 bit times + 50ms).
-    //  
+    //
     // For 2400Bd this means (330 + 11) / 2400 + 0.05 = 188.75 ms (added 11 bit periods to receive first byte).
     // I.e. timeout of 0.2s seems appropriate for 2400Bd.
 
-    handle->t.c_cc[VTIME] = 2; // Timeout in 1/10 sec
+    term->c_cc[VTIME] = 2; // Timeout in 1/10 sec
 
-    cfsetispeed(&(handle->t), B2400);
-    cfsetospeed(&(handle->t), B2400);
+    cfsetispeed(term, B2400);
+    cfsetospeed(term, B2400);
 
 #ifdef MBUS_SERIAL_DEBUG
-    printf("%s: t.c_cflag = %x\n", __PRETTY_FUNCTION__, handle->t.c_cflag);
-    printf("%s: t.c_oflag = %x\n", __PRETTY_FUNCTION__, handle->t.c_oflag);
-    printf("%s: t.c_iflag = %x\n", __PRETTY_FUNCTION__, handle->t.c_iflag);
-    printf("%s: t.c_lflag = %x\n", __PRETTY_FUNCTION__, handle->t.c_lflag);
-#endif 
+    printf("%s: t.c_cflag = %x\n", __PRETTY_FUNCTION__, term->c_cflag);
+    printf("%s: t.c_oflag = %x\n", __PRETTY_FUNCTION__, term->c_oflag);
+    printf("%s: t.c_iflag = %x\n", __PRETTY_FUNCTION__, term->c_iflag);
+    printf("%s: t.c_lflag = %x\n", __PRETTY_FUNCTION__, term->c_lflag);
+#endif
 
-    tcsetattr(handle->fd, TCSANOW, &(handle->t));
+    tcsetattr(handle->fd, TCSANOW, term);
 
-    return handle;    
+    return 0;
 }
 
 //------------------------------------------------------------------------------
 // Set baud rate for serial connection
 //------------------------------------------------------------------------------
 int
-mbus_serial_set_baudrate(mbus_serial_handle *handle, int baudrate)
+mbus_serial_set_baudrate(mbus_handle *handle, int baudrate)
 {
     speed_t speed;
 
     if (handle == NULL)
         return -1;
 
+    mbus_serial_data *serial_data = (mbus_serial_data *) handle->auxdata;
+
     switch (baudrate)
     {
         case 300:
             speed = B300;
-            handle->t.c_cc[VTIME] = 12; // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = 12; // Timeout in 1/10 sec
             break;
 
         case 1200:
             speed = B1200;
-            handle->t.c_cc[VTIME] = 4;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = 4;  // Timeout in 1/10 sec
             break;
 
         case 2400:
             speed = B2400;
-            handle->t.c_cc[VTIME] = 2;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = 2;  // Timeout in 1/10 sec
             break;
 
         case 9600:
             speed = B9600;
-            handle->t.c_cc[VTIME] = 1;  // Timeout in 1/10 sec
+            serial_data->t.c_cc[VTIME] = 1;  // Timeout in 1/10 sec
             break;
 
        default:
@@ -130,19 +131,19 @@ mbus_serial_set_baudrate(mbus_serial_handle *handle, int baudrate)
     }
 
     // Set input baud rate
-    if (cfsetispeed(&(handle->t), speed) != 0)
+    if (cfsetispeed(&(serial_data->t), speed) != 0)
     {
         return -1;
     }
 
     // Set output baud rate
-    if (cfsetospeed(&(handle->t), speed) != 0)
+    if (cfsetospeed(&(serial_data->t), speed) != 0)
     {
         return -1;
     }
 
     // Change baud rate immediately
-    if (tcsetattr(handle->fd, TCSANOW, &(handle->t)) != 0)
+    if (tcsetattr(handle->fd, TCSANOW, &(serial_data->t)) != 0)
     {
         return -1;
     }
@@ -155,7 +156,7 @@ mbus_serial_set_baudrate(mbus_serial_handle *handle, int baudrate)
 //
 //------------------------------------------------------------------------------
 int
-mbus_serial_disconnect(mbus_serial_handle *handle)
+mbus_serial_disconnect(mbus_handle *handle)
 {
     if (handle == NULL)
     {
@@ -163,17 +164,28 @@ mbus_serial_disconnect(mbus_serial_handle *handle)
     }
 
     close(handle->fd);
-    
-    free(handle);
 
     return 0;
 }
 
+void
+mbus_serial_data_free(mbus_handle *handle)
+{
+    mbus_serial_data *serial_data;
+
+    if (handle)
+    {
+        serial_data = (mbus_serial_data *) handle->auxdata;
+        free(serial_data->device);
+        free(serial_data);
+    }
+}
+
 //------------------------------------------------------------------------------
 //
 //------------------------------------------------------------------------------
 int
-mbus_serial_send_frame(mbus_serial_handle *handle, mbus_frame *frame)
+mbus_serial_send_frame(mbus_handle *handle, mbus_frame *frame)
 {
     u_char buff[PACKET_BUFF_SIZE];
     int len, ret;
@@ -225,7 +237,7 @@ mbus_serial_send_frame(mbus_serial_handle *handle, mbus_frame *frame)
 //
 //------------------------------------------------------------------------------
 int
-mbus_serial_recv_frame(mbus_serial_handle *handle, mbus_frame *frame)
+mbus_serial_recv_frame(mbus_handle *handle, mbus_frame *frame)
 {
     char buff[PACKET_BUFF_SIZE];
     int len, remaining, nread, timeouts;
diff --git a/mbus/mbus-serial.h b/mbus/mbus-serial.h
old mode 100644
new mode 100755
index 5c2999a..6203784
--- a/mbus/mbus-serial.h
+++ b/mbus/mbus-serial.h
@@ -19,23 +19,21 @@
 #define MBUS_SERIAL_H
 
 #include <termios.h>
-#include <mbus/mbus.h>
-
-typedef struct _mbus_serial_handle {
+#include "mbus-protocol-aux.h"
+#include "mbus-protocol.h"
 
+typedef struct _mbus_serial_data
+{
     char *device;
-
-    int fd;
     struct termios t;
- 
-} mbus_serial_handle;
+} mbus_serial_data;
 
-
-mbus_serial_handle *mbus_serial_connect(char *device);
-int                 mbus_serial_disconnect(mbus_serial_handle *handle);
-int                 mbus_serial_send_frame(mbus_serial_handle *handle, mbus_frame *frame);
-int                 mbus_serial_recv_frame(mbus_serial_handle *handle, mbus_frame *frame);
-int                 mbus_serial_set_baudrate(mbus_serial_handle *handle, int baudrate);
+int                 mbus_serial_connect(mbus_handle *handle);
+int                 mbus_serial_disconnect(mbus_handle *handle);
+int                 mbus_serial_send_frame(mbus_handle *handle, mbus_frame *frame);
+int                 mbus_serial_recv_frame(mbus_handle *handle, mbus_frame *frame);
+int                 mbus_serial_set_baudrate(mbus_handle *handle, int baudrate);
+void                mbus_serial_data_free(mbus_handle *handle);
 #endif /* MBUS_SERIAL_H */
 
 
diff --git a/mbus/mbus-tcp.c b/mbus/mbus-tcp.c
old mode 100644
new mode 100755
index f29e8ce..f81a1cd
--- a/mbus/mbus-tcp.c
+++ b/mbus/mbus-tcp.c
@@ -21,49 +21,43 @@
 #include <stdio.h>
 #include <string.h>
 #include <strings.h>
+#include <errno.h>
 
-#include <mbus/mbus.h>
-#include <mbus/mbus-tcp.h>
+#include "mbus-tcp.h"
 
 #define PACKET_BUFF_SIZE 2048
 
 //------------------------------------------------------------------------------
 /// Setup a TCP/IP handle.
 //------------------------------------------------------------------------------
-mbus_tcp_handle *
-mbus_tcp_connect(char *host, int port)
+int
+mbus_tcp_connect(mbus_handle *handle)
 {
-    mbus_tcp_handle *handle;
-
+    char error_str[128], *host;
     struct hostent *host_addr;
     struct sockaddr_in s;
     struct timeval time_out;
+    mbus_tcp_data *tcp_data;
+    int port;
 
-    if (host == NULL)
-    {
-        return NULL;
-    }
+    if (handle == NULL)
+        return -1;
 
-    if ((handle = (mbus_tcp_handle *)malloc(sizeof(mbus_tcp_handle))) == NULL)
-    {
-        char error_str[128];
-        snprintf(error_str, sizeof(error_str), "%s: failed to allocate memory for handle\n", __PRETTY_FUNCTION__);
-        mbus_error_str_set(error_str);
-        return NULL;
-    }
+    tcp_data = (mbus_tcp_data *) handle->auxdata;
+    if (tcp_data == NULL || tcp_data->host == NULL)
+        return -1;
 
-    handle->host = host; // strdup ?
-    handle->port = port;
+    host = tcp_data->host;
+    port = tcp_data->port;
 
     //
     // create the TCP connection
     //
-    if ((handle->sock = socket(AF_INET,SOCK_STREAM, 0)) < 0)
+    if ((handle->fd = socket(AF_INET,SOCK_STREAM, 0)) < 0)
     {
-        char error_str[128];
         snprintf(error_str, sizeof(error_str), "%s: failed to setup a socket.", __PRETTY_FUNCTION__);
         mbus_error_str_set(error_str);
-        return NULL;
+        return -1;
     }
 
     s.sin_family = AF_INET;
@@ -72,47 +66,54 @@ mbus_tcp_connect(char *host, int port)
     /* resolve hostname */
     if ((host_addr = gethostbyname(host)) == NULL)
     {
-        char error_str[128];
         snprintf(error_str, sizeof(error_str), "%s: unknown host: %s", __PRETTY_FUNCTION__, host);
         mbus_error_str_set(error_str);
-        free(handle);
-        return NULL;
+        return -1;
     }
 
     memcpy((void *)(&s.sin_addr), (void *)(host_addr->h_addr), host_addr->h_length);
 
-    if (connect(handle->sock, (struct sockaddr *)&s, sizeof(s)) < 0)
+    if (connect(handle->fd, (struct sockaddr *)&s, sizeof(s)) < 0)
     {
-        char error_str[128];
         snprintf(error_str, sizeof(error_str), "%s: Failed to establish connection to %s:%d", __PRETTY_FUNCTION__, host, port);
         mbus_error_str_set(error_str);
-        free(handle);
-        return NULL;
+        return -1;
     }
 
     // Set a timeout
     time_out.tv_sec  = 4; //seconds
     time_out.tv_usec = 0;
-    setsockopt(handle->sock, SOL_SOCKET, SO_SNDTIMEO, &time_out, sizeof(time_out));
-    setsockopt(handle->sock, SOL_SOCKET, SO_RCVTIMEO, &time_out, sizeof(time_out));
+    setsockopt(handle->fd, SOL_SOCKET, SO_SNDTIMEO, &time_out, sizeof(time_out));
+    setsockopt(handle->fd, SOL_SOCKET, SO_RCVTIMEO, &time_out, sizeof(time_out));
 
-    return handle;    
+    return 0;
+}
+
+void
+mbus_tcp_data_free(mbus_handle *handle)
+{
+    mbus_tcp_data *tcp_data;
+
+    if (handle)
+    {
+        tcp_data = (mbus_tcp_data *) handle->auxdata;
+        free(tcp_data->host);
+        free(tcp_data);
+    }
 }
 
 //------------------------------------------------------------------------------
 //
 //------------------------------------------------------------------------------
 int
-mbus_tcp_disconnect(mbus_tcp_handle *handle)
+mbus_tcp_disconnect(mbus_handle *handle)
 {
     if (handle == NULL)
     {
         return -1;
     }
 
-    close(handle->sock);
-    
-    free(handle);
+    close(handle->fd);
 
     return 0;
 }
@@ -121,7 +122,7 @@ mbus_tcp_disconnect(mbus_tcp_handle *handle)
 //
 //------------------------------------------------------------------------------
 int
-mbus_tcp_send_frame(mbus_tcp_handle *handle, mbus_frame *frame)
+mbus_tcp_send_frame(mbus_handle *handle, mbus_frame *frame)
 {
     u_char buff[PACKET_BUFF_SIZE];
     int len, ret;
@@ -139,7 +140,7 @@ mbus_tcp_send_frame(mbus_tcp_handle *handle, mbus_frame *frame)
         return -1;
     }
 
-    if ((ret = write(handle->sock, buff, len)) == len)
+    if ((ret = write(handle->fd, buff, len)) == len)
     {
         //
         // call the send event function, if the callback function is registered
@@ -161,69 +162,59 @@ mbus_tcp_send_frame(mbus_tcp_handle *handle, mbus_frame *frame)
 //------------------------------------------------------------------------------
 //
 //------------------------------------------------------------------------------
-int
-mbus_tcp_recv_frame(mbus_tcp_handle *handle, mbus_frame *frame)
+int mbus_tcp_recv_frame(mbus_handle *handle, mbus_frame *frame)
 {
     char buff[PACKET_BUFF_SIZE];
-    int len, remaining, nread, timeouts;
-    
-    if (handle == NULL || frame == NULL)
-    {
+    int len, remaining, nread;
+
+    if (handle == NULL || frame == NULL) {
         fprintf(stderr, "%s: Invalid parameter.\n", __PRETTY_FUNCTION__);
         return -1;
     }
 
-    memset((void *)buff, 0, sizeof(buff));
+    memset((void *) buff, 0, sizeof(buff));
 
     //
     // read data until a packet is received
     //
     remaining = 1; // start by reading 1 byte
     len = 0;
-    timeouts = 0;
 
     do {
-    
-        if ((nread = read(handle->sock, &buff[len], remaining)) == -1)
-        {
+retry:
+        nread = read(handle->fd, &buff[len], remaining);
+        switch (nread) {
+        case -1:
+            if (errno == EINTR)
+                goto retry;
+
+            if (errno == EAGAIN || errno == EWOULDBLOCK) {
+                mbus_error_str_set("M-Bus tcp transport layer response timeout has been reached.");
+                return -3;
+            }
+
             mbus_error_str_set("M-Bus tcp transport layer failed to read data.");
             return -1;
+        case 0:
+            mbus_error_str_set("M-Bus tcp transport layer connection closed by remote host.");
+            return -4;
+        default:
+            len += nread;
         }
-        
-        if (nread == 0)
-        {
-            timeouts++;
-            
-            if (timeouts >= 3)
-            {
-                // abort to avoid endless loop
-                fprintf(stderr, "%s: Timeout\n", __PRETTY_FUNCTION__);
-                break;
-            }
-        }
-
-        len += nread;
-
     } while ((remaining = mbus_parse(frame, buff, len)) > 0);
-    
-    if (len == 0)
-    {
-        // No data received
-        return -1;
-    }
-    
+
     //
     // call the receive event function, if the callback function is registered
-    // 
+    //
     if (_mbus_recv_event)
         _mbus_recv_event(MBUS_HANDLE_TYPE_TCP, buff, len);
-      
-    if (remaining != 0)
-    {
+
+    if (remaining < 0) {
         mbus_error_str_set("M-Bus layer failed to parse data.");
         return -2;
     }
-  
+
     return 0;
 }
 
+
diff --git a/mbus/mbus-tcp.h b/mbus/mbus-tcp.h
old mode 100644
new mode 100755
index 73a8fc8..6de12a7
--- a/mbus/mbus-tcp.h
+++ b/mbus/mbus-tcp.h
@@ -18,22 +18,20 @@
 #ifndef MBUS_TCP_H
 #define MBUS_TCP_H
 
-#include <mbus/mbus.h>
-
-typedef struct _mbus_tcp_handle {
+#include "mbus-protocol.h"
+#include "mbus-protocol-aux.h"
 
+typedef struct _mbus_tcp_data
+{
     char *host;
-
     int port;
-    int sock;
+} mbus_tcp_data;
 
-} mbus_tcp_handle;
-
-
-mbus_tcp_handle *mbus_tcp_connect(char *host, int port);
-int              mbus_tcp_disconnect(mbus_tcp_handle *handle);
-int              mbus_tcp_send_frame(mbus_tcp_handle *handle, mbus_frame *frame);
-int              mbus_tcp_recv_frame(mbus_tcp_handle *handle, mbus_frame *frame);
+int              mbus_tcp_connect(mbus_handle *handle);
+int              mbus_tcp_disconnect(mbus_handle *handle);
+int              mbus_tcp_send_frame(mbus_handle *handle, mbus_frame *frame);
+int              mbus_tcp_recv_frame(mbus_handle *handle, mbus_frame *frame);
+void             mbus_tcp_data_free(mbus_handle *handle);
 
 #endif /* MBUS_TCP_H */