diff --git a/apps/app_adsiprog.c b/apps/app_adsiprog.c
index 696b1cd7775cbba302164e63610fd490d5ec71a9..7b6e06d50a2c4cfe151a19a7dd8c6d051d7e0c55 100755
--- a/apps/app_adsiprog.c
+++ b/apps/app_adsiprog.c
@@ -666,7 +666,7 @@ static int showdisplay(char *buf, char *name, int id, char *args, struct adsi_sc
 	}
 				   
 	buf[0] = id;
-	buf[1] = (cmd << 6) | (disp->id & 0x2f); 
+	buf[1] = (cmd << 6) | (disp->id & 0x3f); 
 	buf[2] = ((line & 0x1f) << 3) | (flag & 0x7);
 	return 3;
 }