diff --git a/src/main/scala/backBoard/shin/SlaveParser.scala b/src/main/scala/backBoard/shin/SlaveParser.scala
index 987bcb7..5bab42e 100644
--- a/src/main/scala/backBoard/shin/SlaveParser.scala
+++ b/src/main/scala/backBoard/shin/SlaveParser.scala
@@ -674,7 +674,8 @@ trait SlaveParserSync{ this: SlaveParserBase =>
   }
 
   when( RegNext(isSync) & ~isSync ){
-    deltaMstSlvDeltaTimeStamp := (mstDeltaTimeStamp - slvDeltaTimeStamp) >> 1
+    val deltaMstSlvDeltaTimeStamp_org = mstDeltaTimeStamp - slvDeltaTimeStamp
+    deltaMstSlvDeltaTimeStamp := Cat( deltaMstSlvDeltaTimeStamp_org.extract(deltaMstSlvDeltaTimeStamp_org.getWidth-1), deltaMstSlvDeltaTimeStamp_org(deltaMstSlvDeltaTimeStamp_org.getWidth-1, 1) ) //(mstDeltaTimeStamp - slvDeltaTimeStamp) >> 1
   } .elsewhen( RegNext(RegNext(isSync)) & ~RegNext(isSync) ){
     deltaFinal := mstSlvDeltaTimeStamp + deltaMstSlvDeltaTimeStamp
   }