diff --git a/ground/src/experimental/USB_UPLOAD_TOOL/main.cpp b/ground/src/experimental/USB_UPLOAD_TOOL/main.cpp
index 47c7c8982..dc74e2ed6 100644
--- a/ground/src/experimental/USB_UPLOAD_TOOL/main.cpp
+++ b/ground/src/experimental/USB_UPLOAD_TOOL/main.cpp
@@ -93,13 +93,13 @@ int main(int argc, char *argv[])
             }
 
         }
-        else if(args.contains(COMPAREHASH) || args.contains(COMPAREALL))
+        else if(args.contains(COMPARECRC) || args.contains(COMPAREALL))
         {
             int index;
-            if(args.contains(COMPAREHASH))
+            if(args.contains(COMPARECRC))
             {
-                index=args.indexOf(COMPAREHASH);
-                action=OP_DFU::actionCompareHash;
+                index=args.indexOf(COMPARECRC);
+                action=OP_DFU::actionCompareCrc;
             }
             else
             {
@@ -218,6 +218,8 @@ int main(int argc, char *argv[])
                 cout<<"Error:Invalid Device";
                 return -1;
             }
+//            if(dfu.numberOfDevices==1)
+//                dfu.use_delay=false;
             if(!dfu.enterDFU(device))
             {
                 cout<<"Error:Could not enter DFU mode\n";
@@ -225,6 +227,12 @@ int main(int argc, char *argv[])
             }
             if (action==OP_DFU::actionProgram)
             {
+                if(((OP_DFU::device)dfu.devices[device]).Writable==false)
+                {
+                    cout<<"ERROR device not Writable\n";
+                    return false;
+                }
+
                 OP_DFU::Status retstatus=dfu.UploadFirmware(file.toAscii(),verify, device);
                 if(retstatus!=OP_DFU::Last_operation_Success)
                 {
@@ -244,23 +252,28 @@ int main(int argc, char *argv[])
             }
             else if (action==OP_DFU::actionDownload)
             {
+                if(((OP_DFU::device)dfu.devices[device]).Readable==false)
+                {
+                    cout<<"ERROR device not readable\n";
+                    return false;
+                }
                 qint32 size=((OP_DFU::device)dfu.devices[device]).SizeOfCode;
                 bool ret=dfu.SaveByteArrayToFile(file.toAscii(),dfu.StartDownload(size,OP_DFU::FW));
                 return ret;
             }
-            //            else if(action==OP_DFU::downdesc)
-            //            {
-            //                int size=((OP_DFU::device)dfu.devices[device]).SizeOfDesc;
-            //                cout<<"Description:"<<dfu.DownloadDescription(size).toLatin1().data()<<"\n";
-            //            }
-            else if(action==OP_DFU::actionCompareHash)
+            else if(action==OP_DFU::actionCompareCrc)
             {
-                dfu.CompareFirmware(file.toAscii(),OP_DFU::hashcompare);
+                dfu.CompareFirmware(file.toAscii(),OP_DFU::crccompare,device);
                 return 1;
             }
             else if(action==OP_DFU::actionCompareAll)
             {
-                dfu.CompareFirmware(file.toAscii(),OP_DFU::bytetobytecompare);
+                if(((OP_DFU::device)dfu.devices[device]).Readable==false)
+                {
+                    cout<<"ERROR device not readable\n";
+                    return false;
+                }
+                dfu.CompareFirmware(file.toAscii(),OP_DFU::bytetobytecompare,device);
                 return 1;
             }
 
diff --git a/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.cpp b/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.cpp
index 8cfc61ddd..0c846f5b3 100644
--- a/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.cpp
+++ b/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.cpp
@@ -6,6 +6,7 @@
 OP_DFU::OP_DFU(bool _debug): debug(_debug)
 {
     send_delay=10;
+    use_delay=true;
     int numDevices=0;
     cout<<"Please connect device now\n";
     int count=0;
@@ -148,7 +149,8 @@ bool OP_DFU::UploadData(qint32 const & numberOfBytes, QByteArray  & data)
 
         //        }
         // qDebug()<<" Data0="<<(int)data[0]<<" Data0="<<(int)data[1]<<" Data0="<<(int)data[2]<<" Data0="<<(int)data[3]<<" buf6="<<(int)buf[6]<<" buf7="<<(int)buf[7]<<" buf8="<<(int)buf[8]<<" buf9="<<(int)buf[9];
-        delay::msleep(send_delay);
+        //delay::msleep(send_delay);
+        if(int ret=StatusRequest()!=OP_DFU::uploading) return false;
         int result = hidHandle.send(0,buf, BUF_LEN, 5000);
      //   qDebug()<<"sent:"<<result;
         if(result<1)
@@ -165,8 +167,7 @@ bool OP_DFU::UploadData(qint32 const & numberOfBytes, QByteArray  & data)
 }
 OP_DFU::Status OP_DFU::UploadDescription(QString  & description)
 {
-    if(debug)
-        qDebug()<<"Starting uploading description";
+     cout<<"Starting uploading description\n";
     if(description.length()%4!=0)
     {      
         int pad=description.length()/4;
@@ -188,7 +189,7 @@ OP_DFU::Status OP_DFU::UploadDescription(QString  & description)
         return OP_DFU::abort;
     }
     int ret=StatusRequest();
-    qDebug()<<"------"<<ret;
+
     if(debug)
         qDebug()<<"Upload description Status="<<ret;
     return (OP_DFU::Status)ret;
@@ -486,12 +487,13 @@ OP_DFU::Status OP_DFU::UploadFirmware(const QString &sfile, const bool &verify,i
         }
         return OP_DFU::abort;
     }
-    cout<<"Erasing memory";
-    delay::msleep(3000);
+    cout<<"Erasing memory\n";
+    if(StatusRequest()==OP_DFU::abort) return OP_DFU::abort;
     for(int x=0;x<3;++x)
     {
         OP_DFU::Status ret=StatusRequest();
-        qDebug()<<"Erase returned:"<<StatusToString(ret);
+        if(debug)
+            qDebug()<<"Erase returned:"<<StatusToString(ret);
         if (ret==OP_DFU::uploading)
             break;
         else
@@ -518,7 +520,6 @@ OP_DFU::Status OP_DFU::UploadFirmware(const QString &sfile, const bool &verify,i
         return OP_DFU::abort;
     }
     ret=StatusRequest();
-  //  qDebug()<<"---------------------------"<<StatusToString(ret);
     if(ret==OP_DFU::Last_operation_Success)
     {
 
@@ -547,7 +548,7 @@ OP_DFU::Status OP_DFU::UploadFirmware(const QString &sfile, const bool &verify,i
     cout<<"Firmware Uploading succeeded\n";
     return ret;
 }
-OP_DFU::Status OP_DFU::CompareFirmware(const QString &sfile, const CompareType &type)
+OP_DFU::Status OP_DFU::CompareFirmware(const QString &sfile, const CompareType &type,int device)
 {
     cout<<"Starting Firmware Compare...\n";
     QFile file(sfile);
@@ -558,9 +559,7 @@ OP_DFU::Status OP_DFU::CompareFirmware(const QString &sfile, const CompareType &
         return OP_DFU::abort;
     }
     QByteArray arr=file.readAll();
-    QByteArray hash=QCryptographicHash::hash(arr,QCryptographicHash::Sha1);
-    if(debug)
-        qDebug()<<"hash size="<<hash.length()<<" -"<<hash;
+
     if(debug)
         qDebug()<<"Bytes Loaded="<<arr.length();
     if(arr.length()%4!=0)
@@ -571,18 +570,19 @@ OP_DFU::Status OP_DFU::CompareFirmware(const QString &sfile, const CompareType &
         pad=pad-arr.length();
         arr.append(QByteArray(pad,255));
     }
-    if(type==OP_DFU::hashcompare)
+    if(type==OP_DFU::crccompare)
     {
-        //        if(hash==StartDownload(hash.length(),OP_DFU::Hash))
-        //        {
-        //            cout<<"Compare Successfull Hashes MATCH!\n";
-        //        }
-        //        else
-        //        {
-        //            cout<<"Compare failed Hashes DONT MATCH!\n";
-        //        }
-        //        return StatusRequest();
-    }
+         quint32 crc=CRCFromQBArray(arr,devices[device].SizeOfCode);
+         if(crc==devices[device].FW_CRC)
+         {
+             cout<<"Compare Successfull CRC MATCH!\n";
+         }
+         else
+         {
+             cout<<"Compare failed CRC DONT MATCH!\n";
+         }
+         return StatusRequest();
+     }
     else
     {
         if(arr==StartDownload(arr.length(),OP_DFU::FW))
diff --git a/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.h b/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.h
index 15867cf6a..e7a9edf84 100644
--- a/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.h
+++ b/ground/src/experimental/USB_UPLOAD_TOOL/op_dfu.h
@@ -19,7 +19,7 @@ using namespace std;
 #define PROGRAMFW           "-p"     //done
 #define PROGRAMDESC         "-w"     //done
 #define VERIFY              "-v"     //done
-#define COMPAREHASH         "-cc"
+#define COMPARECRC         "-cc"
 #define COMPAREALL          "-ca"
 #define STATUSREQUEST       "-s"    //done
 #define LISTDEVICES         "-ls"   //done
@@ -36,7 +36,7 @@ public:
     };
     enum CompareType
     {
-        hashcompare,
+        crccompare,
         bytetobytecompare
     };
 
@@ -64,7 +64,7 @@ public:
         actionProgramAndVerify,
         actionDownload,
         actionCompareAll,
-        actionCompareHash,
+        actionCompareCrc,
         actionListDevs,
         actionStatusReq,
         actionReset,
@@ -119,11 +119,12 @@ public:
     QList<device> devices;
     int numberOfDevices;
     QString StatusToString(OP_DFU::Status  const & status);
-    OP_DFU::Status CompareFirmware(const QString &sfile, const CompareType &type);
+    OP_DFU::Status CompareFirmware(const QString &sfile, const CompareType &type,int device);
     quint32 CRC32WideFast(quint32 Crc, quint32 Size, quint32 *Buffer);
     quint32 CRCFromQBArray(QByteArray array, quint32 Size);
     void test();
     int send_delay;
+    bool use_delay;
 private:
     bool debug;
     int RWFlags;