diff --git a/ground/src/libs/qymodem/src/qymodem.cpp b/ground/src/libs/qymodem/src/qymodem.cpp
index 9feaf6912..6425af47f 100644
--- a/ground/src/libs/qymodem/src/qymodem.cpp
+++ b/ground/src/libs/qymodem/src/qymodem.cpp
@@ -39,10 +39,10 @@ quint16 QymodemBase::UpdateCRC16(quint16 crcIn, quint8 byte)
         }
 
 
-quint16 QymodemBase::CRC16(const char* data, size_t size)
+quint16 QymodemBase::CRC16(const quint8* data, size_t size)
         {
         quint32 crc = 0;
-        const char* dataEnd = data+size;
+        const quint8* dataEnd = data+size;
         while(data<dataEnd)
                 crc = UpdateCRC16(crc,*data++);
         crc = UpdateCRC16(crc,0);
@@ -51,10 +51,10 @@ quint16 QymodemBase::CRC16(const char* data, size_t size)
         }
 
 
-quint8 QymodemBase::Checksum(const char* data, size_t size)
+quint8 QymodemBase::Checksum(const quint8* data, size_t size)
         {
         int sum = 0;
-        const char* dataEnd = data+size;
+        const quint8* dataEnd = data+size;
         while(data<dataEnd)
                 sum += *data++;
         return sum&0xffu;
@@ -63,9 +63,11 @@ quint8 QymodemBase::Checksum(const char* data, size_t size)
 
 int QymodemBase::InChar(long timeout)
         {
-        char c;
+        quint8 c;
+        char cc;
         Port.setTimeout(timeout);
-        int result =(int)Port.read(&c,1);
+        int result =(int)Port.read(&cc,1);
+        c=(quint8)cc;
         if(result==1)
                 return c;
         if(result==0)
@@ -76,8 +78,8 @@ int QymodemBase::InChar(long timeout)
 
 void QymodemBase::Cancel()
         {
-        const char CancelString[] = { CAN,CAN,CAN,CAN,CAN };
+        const quint8 CancelString[] = { CAN,CAN,CAN,CAN,CAN };
         Port.setTimeout(1000);
-        Port.write(CancelString,sizeof(CancelString));
+        Port.write((char*)CancelString,sizeof(CancelString));
          }
 
diff --git a/ground/src/libs/qymodem/src/qymodem.h b/ground/src/libs/qymodem/src/qymodem.h
index 9583446a8..db11a9bbc 100644
--- a/ground/src/libs/qymodem/src/qymodem.h
+++ b/ground/src/libs/qymodem/src/qymodem.h
@@ -26,6 +26,8 @@ class QymodemBase: public QThread
 signals:
     void Error(QString,int);
     void Information(QString,int);
+    ///
+    void Percent(int);
 
 protected:
 
@@ -41,7 +43,7 @@ protected:
 
         @return Sum of bytes in data, modulo 256.
         */
-    quint8 Checksum(const char* data, size_t size);
+    quint8 Checksum(const quint8* data, size_t size);
 
     /**
         Calculate CRC for a block of data.
@@ -51,7 +53,7 @@ protected:
 
         @return CRC of data.
         */
-    quint16 CRC16(const char* data, size_t size);
+    quint16 CRC16(const quint8* data, size_t size);
 
     /**
         Update CRC value by accumulating another byte of data.
@@ -107,7 +109,6 @@ protected:
         */
 
     QextSerialPort& Port;
-    int percent;
 };
 
 
diff --git a/ground/src/libs/qymodem/src/qymodem_tx.cpp b/ground/src/libs/qymodem/src/qymodem_tx.cpp
index ccd252d9b..d8383d662 100644
--- a/ground/src/libs/qymodem/src/qymodem_tx.cpp
+++ b/ground/src/libs/qymodem/src/qymodem_tx.cpp
@@ -79,7 +79,7 @@ int QymodemTx::SendInitialise(unsigned timeout)
         int c;
         for(;;)
                 {
-                const unsigned timeoutStep = 10;
+                const unsigned timeoutStep = 1000;
                 c = InChar(timeoutStep);
                 if(c=='G')
                         {
@@ -123,9 +123,9 @@ A zero sized block terminates the transfer.
 
 @pre SendInitialise() must have been successful.
 */
-int   QymodemTx::SendBlock(const char* data, size_t size)
+int   QymodemTx::SendBlock(const quint8* data, size_t size)
         {
-        char block[1+2+1024+2];	// buffer to hold data in the block
+        quint8 block[1+2+1024+2];	// buffer to hold data in the block
         int retryCount = 10;		// number of attempts to send the block
         bool waitForBlockACK = WaitForBlockACK;
 
@@ -173,13 +173,13 @@ do_retry:
         if(!retryCount--)
                 return ErrorBlockRetriesExceded;
 
-        char* out = block;
+        quint8* out = block;
         size_t outSize = blockSize;
         for(;;)
                 {
                 // send some data...
                 Port.setTimeout(1000);;
-                int result = (int)Port.write(out,outSize);
+                int result = (int)Port.write((char*)out,outSize);
                 if(result<0)
                         return result; // return error
                 if(result==0)
@@ -259,7 +259,7 @@ A zero sized block terminates the transfer.
 
 @pre SendInitialise() must have been successful.
 */
-int QymodemTx::SendData(const char* data, size_t size)
+int QymodemTx::SendData(const quint8* data, size_t size)
         {
         do
                 {
@@ -290,8 +290,9 @@ int QymodemTx::SendAll(InStream& in)
         do
                 {
                 // get data from input stream...
-                char data[1024];
-                int result = in.In(data,sizeof(data),&percent);
+                quint8 data[1024];
+                int result = in.In(data,sizeof(data));
+                emit Percent(in.percent);
                 if(result<0)
                         return ErrorInputStreamError;
 
@@ -316,11 +317,11 @@ Construct the data for the first block of a Y-Modem transfer.
 
 @return Zero if successful, or a negative error value if failed.
 */
-int QymodemTx::MakeBlock0(char* buffer, const char* fileName, size_t fileSize)
+int QymodemTx::MakeBlock0(quint8* buffer, const char* fileName, size_t fileSize)
         {
         // setup buffer for block 0...
-        char* out = buffer;
-        char* outEnd = buffer+128-1;
+        quint8* out = buffer;
+        quint8* outEnd = buffer+128-1;
         memset(buffer,0,128);
 
         // copy file name to block data...
@@ -378,7 +379,7 @@ int QymodemTx::SendX(InStream& in, unsigned timeout, bool kMode)
 int QymodemTx::SendY(const char* fileName, size_t size, InStream& in, unsigned timeout)
         {
         Use1KBlocks = true;
-        char buffer[128];
+        quint8 buffer[128];
         int result = MakeBlock0(buffer,fileName,size);
         if(result<0)
                 return result;
@@ -413,7 +414,7 @@ int QymodemTx::SendY(const char* fileName, size_t size, InStream& in, unsigned t
         result = SendBlock(buffer,sizeof(buffer));
         if(result<0)
                 return result;
-
+        emit Percent(100);
         return 0;
         }
 
diff --git a/ground/src/libs/qymodem/src/qymodem_tx.h b/ground/src/libs/qymodem/src/qymodem_tx.h
index a62e1ce4e..2643e1577 100755
--- a/ground/src/libs/qymodem/src/qymodem_tx.h
+++ b/ground/src/libs/qymodem/src/qymodem_tx.h
@@ -44,6 +44,7 @@ public:
         class InStream
                 {
         public:
+             int percent;
                 /**
                 Read data from the stream.
 
@@ -52,7 +53,7 @@ public:
 
                 @return Number of bytes successfully read, or a negative error value if failed.
                 */
-                virtual int In(char* data, size_t size, int * percent) =0;
+                virtual int In(quint8* data, size_t size) =0;
 
                 /**
                 Empty destructor to avoid compiler warnings.
@@ -105,10 +106,10 @@ public:
 
 private:
         int SendInitialise(unsigned timeout);
-        int SendBlock(const char* data, size_t size);
-        int SendData(const char* data, size_t size);
+        int SendBlock(const quint8* data, size_t size);
+        int SendData(const quint8* data, size_t size);
         int SendAll(InStream& in);
-        int MakeBlock0(char* buffer, const char* fileName, size_t fileSize);
+        int MakeBlock0(quint8* buffer, const char* fileName, size_t fileSize);
         int ProcessResponse(int c);
 private:
         size_t BlockNumber;
diff --git a/ground/src/libs/qymodem/src/qymodemsend.cpp b/ground/src/libs/qymodem/src/qymodemsend.cpp
index dce20c914..53803b794 100644
--- a/ground/src/libs/qymodem/src/qymodemsend.cpp
+++ b/ground/src/libs/qymodem/src/qymodemsend.cpp
@@ -20,12 +20,8 @@
 QymodemSend::QymodemSend(QextSerialPort& port)
     : QymodemTx(port)
     {
-        percent=0;
+
     }
-int QymodemSend::PercentSend()
-{
-    return percent;
-}
 
 /**
 Class for presenting a file as a input stream.
@@ -44,6 +40,8 @@ public:
 
         @return Zero if successful, or a negative error value if failed.
         */
+
+
     int Open(const char* fileName)
     {
         File = fopen(fileName,"rb");
@@ -95,9 +93,11 @@ public:
 
         @return Zero if successful, or a negative error value if failed.
         */
-    int In(char* data, size_t size, int * percent)
+    int In(quint8* data, size_t size)
     {
-        *percent = TotalSize ? ((quint64)TransferredSize*(quint64)100)/(quint64)TotalSize : 0;
+       // mutex.lock();
+        percent = TotalSize ? ((quint64)TransferredSize*(quint64)100)/(quint64)TotalSize : 0;
+        //mutex.unlock();
         fflush(stdout);
         size=fread(data,sizeof(quint8),size,File);
         if(size)
@@ -110,9 +110,11 @@ public:
         return 0;
     }
 private:
+  //  QMutex mutex;
     FILE* File;
     size_t TotalSize;
     size_t TransferredSize;
+
 };
 
 
@@ -140,10 +142,11 @@ void QymodemSend::Send()
     error = SendY(FileName,source.Size(),source,Timeout);
     if(error)
     {
-        emit Error("Error during file transfer, error "+QString(error),error);
+        emit Error("Error during file transfer, error "+QString::number(error),error);
     }
     else
     {
+
         emit Information("Sent OK",QymodemSend::InfoSent);
     }
     source.Close();
@@ -157,7 +160,7 @@ int QymodemSend::SendFile(QString filename)
         emit Error("File not found",QymodemSend::ErrorFileNotFound);
         return QymodemSend::ErrorFileNotFound;
     }
-    if(!Port.open(QIODevice::ReadWrite| QIODevice::Unbuffered))
+    if(!Port.open(QIODevice::ReadWrite))
     {
         emit Error("Could not open port",QymodemSend::ErrorCoulNotOpenPort);
         return QymodemSend::ErrorCoulNotOpenPort;
@@ -191,7 +194,7 @@ void QymodemSend::run()
         emit Error("File not found",QymodemSend::ErrorFileNotFound);
         return;
     }
-    if(!Port.open(QIODevice::ReadWrite| QIODevice::Unbuffered))
+    if(!Port.open(QIODevice::ReadWrite))
     {
         emit Error("Could not open port",QymodemSend::ErrorCoulNotOpenPort);
         return;
diff --git a/ground/src/libs/qymodem/src/qymodemsend.h b/ground/src/libs/qymodem/src/qymodemsend.h
index 20f532900..7e2bb3a8c 100644
--- a/ground/src/libs/qymodem/src/qymodemsend.h
+++ b/ground/src/libs/qymodem/src/qymodemsend.h
@@ -28,7 +28,6 @@ public:
     QymodemSend(QextSerialPort& port);
     int SendFile(QString filename);
     int SendFileT(QString filename);
-    int PercentSend();
 
 private:
     void run();