diff --git a/DeviceCore.cpp b/DeviceCore.cpp
index a54fc9c..3515a6f 100644
--- a/DeviceCore.cpp
+++ b/DeviceCore.cpp
@@ -1404,8 +1404,10 @@ bool CDeviceCore::SetValue( TDeviceParam * Param, const char * Value, const int
 bool CDeviceCore::GetValue( TDeviceParam * Param, char * Value, int &Len )
 {
     // Validate
-    if (!Param || !Value)
+    if (!Param || !Value) {
+        Value[0] = 0;
         return false;
+    }
 
     // Check if return value longer than actual value
     switch (Param->DataType)
@@ -1448,6 +1450,7 @@ bool CDeviceCore::GetValue( TDeviceParam * Param, char * Value, int &Len )
             break;
 
         default :
+            Value[0] = 0;
             break;
     }
     return true;
@@ -1512,8 +1515,13 @@ bool CDeviceCore::GetCmdParam( const char * Start, char * Param, char ** NextPar
     int     ParamLen;
 
     // Get length of param
-    if ((NextDelimeter = strchr( (char*)Start, ',' ))) {
-        ParamLen = NextDelimeter - Start;
+    if (!Start || !*Start) {
+        Param[0]  = 0;
+        NextParam = NULL;
+        return false;
+    }
+    else if ((NextDelimeter = strchr( (char*)Start, ',' ))) {
+        ParamLen  = NextDelimeter - Start;
         *NextParam = NextDelimeter + 1;
     }
     else {
@@ -1537,162 +1545,147 @@ bool CDeviceCore::GetCmdParam( const char * Start, char * Param, char ** NextPar
 int CDeviceCore::HandleCommand( const char *ChannelName, const char * Data, const int MaxLen )
 {
     int             Len;
-    char            ParamName[50];
+    char            Value[50];
     char            * NextParam     = NULL;
     TDevice         * Device        = NULL;
-    TDeviceParam    * Param      = NULL;
+    TDeviceParam    * Param         = NULL;
     char            OutputStr[250];
+    bool            Error           = false;
 
     // Show accepted input
     Log->Output( LogLevel, dlHigh, loNormal, Data, MaxLen, "%s/%s: Channel '%s' - IN:",
                  ProcessName, Name, ChannelName );
 
     // Get command command
-    GetCmdParam( Data, ParamName, &NextParam );
-    if (!strcasecmp( "get", ParamName ))
+    GetCmdParam( Data, Value, &NextParam );
+    if (!strcasecmp( "get", Value ))
     {
-        // Check for additional parameters
-        if (!NextParam) {
-            // No Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Missing 'get' parameters",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
+        // Validate parameters
+        if (!GetCmdParam( NextParam, Value, &NextParam)) {
+            strcpy( OutputStr, "- Missing device name" );
+            Error = true;
+        }
+        else if (!(Device = GetDeviceByName( Value ))) {
+            strcpy( OutputStr, "- Device not found");
+            Error = true;
+        }
+        else if (!GetCmdParam( NextParam, Value, &NextParam )) {
+            strcpy( OutputStr, "- Missing parameter name" );
+            Error = true;
+        }
+        else if (!(Param = GetDeviceParam( Device, Value ))) {
+            strcpy( OutputStr, "- Device parameter not found");
+            Error = true;
+        }
+        else if (NextParam) {
+            strcpy( OutputStr, "- Too many parameters");
+            Error = true;
+        }
+        else {
+            sprintf( OutputStr, "> %s,%s = ", Device->Name, Param->Name );
+            Len = MaxLen - strlen(OutputStr) - 1;
+
+            if (!GetValue( (TDeviceParam*)Param, &OutputStr[ strlen(OutputStr) ], Len )) {
+                strcpy( OutputStr, "- Error getting parameter");
+                Error = true;
+            }
+            else {
+                strcat( OutputStr, "\n" );
+                Output( ChannelName, OutputStr, strlen(OutputStr) );
+            }
         }
 
-        // Get device name
-        GetCmdParam( NextParam, ParamName, &NextParam );
-        if (!(Device = GetDeviceByName( ParamName ))) {
-            // Unknown Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unknown 'get' Device: '%s'",
-                          ProcessName, Name, ChannelName, ParamName );
-            return MaxLen;
+        // Report error
+        if (Error) {
+            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' Get",
+                          ProcessName, Name, ChannelName, OutputStr );
+            strcat( OutputStr, "\n" );
+            Output( ChannelName, OutputStr, strlen(OutputStr) );
         }
-
-        // Get parameter name
-        GetCmdParam( NextParam, ParamName, &NextParam );
-        if (!(Param = GetDeviceParam( Device, ParamName ))) {
-            // Unknown Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unknown 'get' Param: '%s'",
-                          ProcessName, Name, ChannelName, ParamName );
-            return MaxLen;
-        }
-
-        // Check for additional parameters
-        if (NextParam) {
-            // Unused Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unnecessary 'get' parameters",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
-        }
-
-        // Build reply
-        sprintf( OutputStr, "get,%s,", Param->Name );
-        Len = MaxLen - strlen(OutputStr);
-
-        // Insert value
-        if (!GetValue( (TDeviceParam*)Param, &OutputStr[ strlen(OutputStr) ], Len ))
-            return false;
-
-        // Send reply
-        strcat( OutputStr, "\n" );
-        Output( ChannelName, OutputStr, strlen(OutputStr) );
-        return true;
     }
-    else if (!strcasecmp( "set", ParamName ))
+    else if (!strcasecmp( "set", Value ))
     {
-        // Check for additional parameters
-        if (!NextParam) {
-            // No Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Missing 'set' parameters",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
+        // Validate parameters
+        if (!GetCmdParam( NextParam, Value, &NextParam)) {
+            strcpy( OutputStr, "- Missing device name" );
+            Error = true;
+        }
+        else if (!(Device = GetDeviceByName( Value ))) {
+            strcpy( OutputStr, "- Device not found");
+            Error = true;
+        }
+        else if (!GetCmdParam( NextParam, Value, &NextParam )) {
+            strcpy( OutputStr, "- Missing parameter name" );
+            Error = true;
+        }
+        else if (!(Param = GetDeviceParam( Device, Value ))) {
+            strcpy( OutputStr, "- Device parameter not found");
+            Error = true;
+        }
+        else if (!GetCmdParam( NextParam, Value, &NextParam )) {
+            strcpy( OutputStr, "- Missing set value");
+            Error = true;
+        }
+        else if (NextParam) {
+            strcpy( OutputStr, "- Too many parameters");
+            Error = true;
+        }
+        else {
+            if (!SetValue( Param, Value, strlen(Value), true )) {
+                strcpy( OutputStr, "- Error seting parameter");
+                Error = true;
+            }
+            else {
+                sprintf( OutputStr, "> set %s,%s = %s\n", Device->Name, Param->Name, Value );
+                Output( ChannelName, OutputStr );
+            }
         }
 
-        // Get Device name
-        GetCmdParam( NextParam, ParamName, &NextParam );
-        if (!(Device = GetDeviceByName( ParamName ))) {
-            // Unknown Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unknown 'set' Device: '%s'",
-                          ProcessName, Name, ChannelName, ParamName );
-            return MaxLen;
+        // Report error
+        if (Error) {
+            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' Set",
+                          ProcessName, Name, ChannelName, OutputStr );
+            strcat( OutputStr, "\n" );
+            Output( ChannelName, OutputStr, strlen(OutputStr) );
         }
-
-        // Get parameter name
-        GetCmdParam( NextParam, ParamName, &NextParam );
-        if (!(Param = GetDeviceParam( Device, ParamName ))) {
-            // Unknown Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unknown 'set' Param: '%s'",
-                          ProcessName, Name, ChannelName, ParamName );
-            return MaxLen;
-        }
-
-        // Get parameter value
-        GetCmdParam( NextParam, ParamName, &NextParam );
-        if (strlen(ParamName) == 0) {
-            // No Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - No 'set' value parameter",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
-        }
-
-        // Check for additional parameters
-        if (NextParam) {
-            // Unused Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unnecessary 'set' parameters",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
-        }
-
-        // Set value
-        Len = MaxLen;
-        if (!SetValue( Param, ParamName, Len, true ))
-            return false;
-
-        // Build & send reply
-        sprintf( OutputStr, "set,%s,%s\n", Param->Name, ParamName );
-        Output( ChannelName, OutputStr );
-        return true;
     }
-    else if (!strcasecmp( "status", ParamName ))
+    else if (!strcasecmp( "status", Value ))
     {
-        // Check for additional parameters
-        if (!NextParam) {
-            // No Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Missing 'status' parameters",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
+        // Validate parameters
+        if (!GetCmdParam( NextParam, Value, &NextParam)) {
+            strcpy( OutputStr, "- Missing device name" );
+            Error = true;
+        }
+        else if (!(Device = GetDeviceByName( Value ))) {
+            strcpy( OutputStr, "- Device not found");
+            Error = true;
+        }
+        else if (NextParam) {
+            strcpy( OutputStr, "- Too many parameters");
+            Error = true;
+        }
+        else {
+            sprintf( OutputStr, "> %s - %s\n", Device->Name, ((Device->Online)? "online" : "offline") );
+            Output( ChannelName, OutputStr );
         }
 
-        // Get Device name
-        GetCmdParam( NextParam, ParamName, &NextParam );
-        if (!(Device = GetDeviceByName( ParamName ))) {
-            // Unknown Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unknown 'status' Device: '%s'",
-                          ProcessName, Name, ChannelName, ParamName );
-            return MaxLen;
+        // Report error
+        if (Error) {
+            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' Status",
+                          ProcessName, Name, ChannelName, OutputStr );
+            strcat( OutputStr, "\n" );
+            Output( ChannelName, OutputStr, strlen(OutputStr) );
         }
-
-        // Check for additional parameters
-        if (NextParam) {
-            // Unused Parameters
-            Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unnecessary 'status' parameters",
-                          ProcessName, Name, ChannelName );
-            return MaxLen;
-        }
-
-        // Build & send reply
-        sprintf( OutputStr, "status,%s,%d\n", Device->Name, Device->Online );
-        Output( ChannelName, OutputStr );
-        return true;
     }
     else
     {
         // Unrecognised command
-        Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s' - Unrecognized command: '%s'",
-                      ProcessName, Name, ChannelName, ParamName );
-        return MaxLen;
+        strcpy( OutputStr, "- Unknown command");
+        Log->Message( LogLevel, dlMedium, "%s/%s: Channel '%s', %s%s",
+                      ProcessName, Name, ChannelName, Value, OutputStr );
+        strcat( OutputStr, " (comma separated values)\n" );
+        Output( ChannelName, OutputStr, strlen(OutputStr) );
     }
-
     return MaxLen;
 }
 //---------------------------------------------------------------------------
diff --git a/DeviceCore.h b/DeviceCore.h
index f4bad96..2cd7347 100644
--- a/DeviceCore.h
+++ b/DeviceCore.h
@@ -231,6 +231,11 @@ protected:
             Param = &((*Param)->Next);
         return Param;
     }
+    inline TDeviceParamGroup * GetNextParamGroup( TDevice * Device, TDeviceParamGroup * LastParamGroup = NULL ) {
+        if (!Device) return NULL;
+        TDeviceParamGroup * ParamGroup = (LastParamGroup)? LastParamGroup->NextGroup : Device->FirstParamGroup;
+        return ParamGroup;
+    }
     inline TDeviceParam * GetNextReadParam( TDevice * Device, TDeviceParam * LastParam = NULL ) {
         if (!Device) return NULL;
         TDeviceParam * Param = (LastParam)? LastParam->Next : Device->FirstParam;