diff --git a/.gitignore b/.gitignore
index 25609dc..efbcf41 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@
 vendor/
 *.temp
 .vscode
+.DS_Store
diff --git a/spec/tlv.t.go b/spec/tlv.t.go
index 8d114df..84671eb 100644
--- a/spec/tlv.t.go
+++ b/spec/tlv.t.go
@@ -36,9 +36,9 @@ func (t T) IsNodeMode() bool {
 
 // SetNodeMode will set T to indicates this packet contains
 // other packets.
-func (t T) SetNodeMode(flag bool) {
+func (t *T) SetNodeMode(flag bool) {
 	if flag {
-		t |= flagBitNode
+		*t |= flagBitNode
 	}
 }