diff --git a/src/floppy.js b/src/floppy.js
index 3961317453..0d299f696d 100644
--- a/src/floppy.js
+++ b/src/floppy.js
@@ -318,7 +318,10 @@ FloppyController.prototype.port3F2_write = function(value)
     dbg_log("enable dma/irq: " + !!(value & 8), LOG_FLOPPY);
     dbg_log("reset fdc: " + !!(value & 4), LOG_FLOPPY);
     dbg_log("drive select: " + (value & 3), LOG_FLOPPY);
-    dbg_assert((value & 3) == 0, "guest: fdb not implemented");
+    if((value & 3) != 0)
+    {
+        dbg_log("guest: fdb not implemented");
+    }
     dbg_log("DOR = " + h(value), LOG_FLOPPY);
 
     this.dor = value;