diff --git a/fhem/CHANGED b/fhem/CHANGED
index 0b1c5dc83..1687da2d7 100644
--- a/fhem/CHANGED
+++ b/fhem/CHANGED
@@ -1,5 +1,6 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+  - change: 66_ECMD: ReadyFn added (fixes issue under Windows)
   - change: 02_RSS: use a GUID in RSS; urlq source for img command
   - feature: 70_PushNotifier improve usebility, configuration without cURL (xusader)
   - bugfix: SYSMON: prevent empty line im log by userReadings
diff --git a/fhem/FHEM/66_ECMD.pm b/fhem/FHEM/66_ECMD.pm
index 23df467b2..5173a3fdd 100644
--- a/fhem/FHEM/66_ECMD.pm
+++ b/fhem/FHEM/66_ECMD.pm
@@ -41,7 +41,7 @@ sub ECMD_Clear($);
 #sub ECMD_Parse($$$$$);
 sub ECMD_Read($);
 sub ECMD_ReadAnswer($$);
-#sub ECMD_Ready($);
+sub ECMD_Ready($);
 sub ECMD_Write($$$);
 
 
@@ -61,6 +61,7 @@ ECMD_Initialize($)
 # Consumer
   $hash->{DefFn}   = "ECMD_Define";
   $hash->{UndefFn} = "ECMD_Undef";
+  $hash->{ReadyFn} = "ECMD_Ready";
   $hash->{GetFn}   = "ECMD_Get";
   $hash->{SetFn}   = "ECMD_Set";
   $hash->{AttrFn}  = "ECMD_Attr";
@@ -150,6 +151,25 @@ ECMD_Log($$$)
   Log3 $hash, $loglevel , "$name: $logmsg";
 }
 
+#####################################
+sub
+ECMD_Ready($) 
+{
+  my ($hash) = @_;
+
+  return DevIo_OpenDev($hash, 1, "ECMD_DoInit")
+                if($hash->{STATE} eq "disconnected");
+
+  # This is relevant for windows/USB only
+  my $po = $hash->{USBDev};
+  my ($BlockingFlags, $InBytes, $OutBytes, $ErrorFlags);
+  if($po) {
+    ($BlockingFlags, $InBytes, $OutBytes, $ErrorFlags) = $po->status;
+  }
+  return ($InBytes && $InBytes>0);
+}
+
+
 #####################################
 sub
 ECMD_SimpleRead($)