qt: fix write data is slow

Author: ssp97

qt/writer.cpp

@@ -301,7 +301,7 @@ int Writer::writeData()
             break;
     }
 
-    if (read(pbuf, bufSize))
+    if (read(pbuf, writeDataAckLen))
         return -1;
 
     return 0;

qt/writer.h

@@ -16,6 +16,7 @@ class Writer : public QObject
     Q_OBJECT
 
     static const uint32_t bufSize = 64;
+    static const uint32_t writeDataAckLen = 10;
 
     SerialPort *serialPort = nullptr;
     QString portName;