Index: /trunk/FACT++/gui/MainWindow.cc
===================================================================
--- /trunk/FACT++/gui/MainWindow.cc	(revision 10736)
+++ /trunk/FACT++/gui/MainWindow.cc	(revision 10737)
@@ -231,5 +231,5 @@
     const uint16_t idx = fPixelIdx->value();
 
-    const uint8_t d[3] = { idx&0xff, idx>>8, !b };
+    const uint8_t d[3] = { uint8_t(idx&0xff), uint8_t(idx>>8), !b };
 
     Dim::SendCommand("FTM_CONTROL/DISABLE_PIXEL", d);