diff --git a/src/main/scala/Switch/DMA.scala b/src/main/scala/Switch/DMA.scala
index 2156c6c..d6e3d39 100644
--- a/src/main/scala/Switch/DMA.scala
+++ b/src/main/scala/Switch/DMA.scala
@@ -33,7 +33,7 @@ abstract class DMAMstBase(val edgeOut: TLEdgeOut)(implicit p: Parameters) extend
 
   val rxBuff = Module(new RxBuff(8))
   val txBuff = Module(new TxBuff(0))
-  rxBuff.io.header.ready := true.B
+  rxBuff.headerIO.ready := true.B
 
 
   def stateIdle = 0.U
diff --git a/src/main/scala/Switch/PiPoBuff.scala b/src/main/scala/Switch/PiPoBuff.scala
new file mode 100644
index 0000000..91d77fa
--- /dev/null
+++ b/src/main/scala/Switch/PiPoBuff.scala
@@ -0,0 +1,147 @@
+package Switch
+
+import chisel3._
+import chisel3.util._
+
+import MAC._
+
+
+
+
+
+
+
+
+
+class PiPoBuffBase[T<:Data]( dp: Int, val threshold: Int = 32) extends Module{
+
+  class PiPoBuffIO extends Bundle{
+    val enq = Flipped(Decoupled(new Mac_Stream_Bundle))
+    val deq = Decoupled(new Mac_Stream_Bundle)
+  }
+
+  val io: PiPoBuffIO = IO(new PiPoBuffIO)
+
+  val isEnqPi = RegInit(true.B)
+  val isEnqPo = ~isEnqPi
+
+  val isDeqPi = RegInit(true.B)
+  val isDeqPo = ~isDeqPi
+
+
+  val buff = for( i <- 0 until 2 ) yield { Module(new Queue( new Mac_Stream_Bundle, dp )) }
+  val isReach = for( i <- 0 until 2 ) yield { RegInit(false.B) }
+  val cnt = RegInit(0.U((log2Ceil(dp)).W))
+
+
+
+  buff(0).io.enq.valid := isEnqPi & io.enq.valid
+  buff(0).io.enq.bits  := io.enq.bits
+
+  buff(1).io.enq.valid := isEnqPo & io.enq.valid
+  buff(1).io.enq.bits  := io.enq.bits
+
+  io.enq.ready :=
+    Mux1H(Seq(
+      isEnqPi -> buff(0).io.enq.ready,
+      isEnqPo -> buff(1).io.enq.ready
+    ))
+
+  when( io.enq.fire & io.enq.bits.isLast ){
+    isEnqPi := ~isEnqPi
+  }
+
+
+
+  when( io.enq.fire ){
+    when( io.enq.bits.isStart ){
+      cnt := 0.U      
+    } .otherwise{
+      cnt := cnt + 1.U
+    }
+  }
+
+
+
+  when( io.enq.fire ){
+    when( io.enq.bits.isStart ){
+      when( isEnqPi ){ isReach(0) := false.B }
+      when( isEnqPo ){ isReach(1) := false.B }
+    } .elsewhen(
+      io.enq.bits.isLast ||
+      (if( threshold != 0 ) { cnt === threshold.U } else {false.B})
+      ){
+      when( isEnqPi ){ isReach(0) := true.B }
+      when( isEnqPo ){ isReach(1) := true.B }
+    }
+  }
+
+
+  when( io.deq.fire & io.deq.bits.isLast ){
+    isDeqPi := ~isDeqPi
+  }
+
+  io.deq.valid :=
+    Mux1H(Seq(
+      isDeqPi -> ( buff(0).io.deq.valid & isReach(0) ),
+      isDeqPo -> ( buff(1).io.deq.valid & isReach(1) ),
+    ))
+
+  io.deq.bits :=
+    Mux1H(Seq(
+      isDeqPi -> buff(0).io.deq.bits,
+      isDeqPo -> buff(1).io.deq.bits,
+    ))
+
+  buff(0).io.deq.ready := io.deq.ready & isReach(0) & isDeqPi
+  buff(1).io.deq.ready := io.deq.ready & isReach(1) & isDeqPo
+}
+
+
+
+
+class RxBuff(threshold: Int = 8) extends PiPoBuffBase(2048, threshold){
+  val headerIO = IO(Decoupled(Vec( 20, UInt(8.W) ) ))
+
+
+
+  val header = for( i <- 0 until 2 ) yield { Reg(Vec( 20, UInt(8.W) )) }
+  val hValid = for( i <- 0 until 2 ) yield { RegInit(false.B) }
+
+
+  when( io.enq.fire ){
+    when( cnt < 20.U ){
+      when( isEnqPi ){ header(0)(cnt) := io.enq.bits.data } 
+      .elsewhen( isEnqPo ){ header(1)(cnt) := io.enq.bits.data
+      } .otherwise{
+        assert(false.B, "Assert Failed, Rx Under Run")
+      }
+    }
+  }
+
+
+  when( headerIO.fire ){
+    when( isDeqPi ) { hValid(0) := false.B }
+    when( isDeqPo ) { hValid(1) := false.B }
+  } .elsewhen( io.enq.fire & cnt === 20.U ){
+    when( isEnqPi ) { hValid(0) := true.B }
+    when( isEnqPo ) { hValid(1) := true.B }
+  }
+
+
+    headerIO.valid := 
+      Mux1H(Seq(
+        isDeqPi -> hValid(0),
+        isDeqPo -> hValid(1),
+      ))
+      
+    headerIO.bits  := 
+      Mux1H(Seq(
+        isDeqPi -> header(0),
+        isDeqPo -> header(1),
+      ))
+
+}
+
+class TxBuff(threshold: Int = 8) extends PiPoBuffBase(2048, threshold)
+
diff --git a/src/main/scala/Switch/RxBuff.scala b/src/main/scala/Switch/RxBuff.scala
deleted file mode 100644
index c997485..0000000
--- a/src/main/scala/Switch/RxBuff.scala
+++ /dev/null
@@ -1,142 +0,0 @@
-package Switch
-
-import chisel3._
-import chisel3.util._
-
-import MAC._
-
-
-
-
-class RxBuffIO extends Bundle{
-  val enq = Flipped(Decoupled(new Mac_Stream_Bundle))
-  val deq = Decoupled(new Mac_Stream_Bundle)
-  val header = Decoupled(Vec( 20, UInt(8.W) ) )
-}
-
-
-
-
-class RxBuffBase(val threshold: Int = 32) extends Module{
-  val io: RxBuffIO = IO(new RxBuffIO)
-
-  val isEnqPi = RegInit(true.B)
-  val isEnqPo = ~isEnqPi
-
-  val isDeqPi = RegInit(true.B)
-  val isDeqPo = ~isDeqPi
-
-
-  val buff = for( i <- 0 until 2 ) yield { Module(new Queue( new Mac_Stream_Bundle, 2048 )) }
-
-
-  val header = for( i <- 0 until 2 ) yield { Reg(Vec( 20, UInt(8.W) )) }
-  val hValid = for( i <- 0 until 2 ) yield { RegInit(false.B) }
-  val isReach = for( i <- 0 until 2 ) yield { RegInit(false.B) }
-  
-  val recCnt = RegInit(0.U(12.W))
-
-
-
-}
-
-
-trait RxBuffEnq{ this: RxBuffBase =>
-
-
-
-  buff(0).io.enq.valid := isEnqPi & io.enq.valid
-  buff(0).io.enq.bits  := io.enq.bits
-
-  buff(1).io.enq.valid := isEnqPo & io.enq.valid
-  buff(1).io.enq.bits  := io.enq.bits
-
-  io.enq.ready := (isEnqPi & buff(0).io.enq.ready) | (isEnqPo & buff(1).io.enq.ready)
-
-  when( io.enq.fire & io.enq.bits.isLast ){
-    isEnqPi := ~isEnqPi
-  }
-
-
-
-  when( io.enq.fire ){
-    when( io.enq.bits.isStart ){
-      recCnt := 0.U      
-    } .otherwise{
-      recCnt := recCnt + 1.U
-    }
-  }
-
-  when( io.enq.fire ){
-    when( recCnt < 20.U ){
-      when( isEnqPi ){ header(0)(recCnt) := io.enq.bits.data } 
-      .elsewhen( isEnqPo ){ header(1)(recCnt) := io.enq.bits.data
-      } .otherwise{
-        assert(false.B, "Assert Failed, Rx Under Run")
-      }
-    }
-  }
-
-  when( io.enq.fire ){
-    when( io.enq.bits.isStart ){
-      when( isEnqPi ){ isReach(0) := false.B }
-      when( isEnqPo ){ isReach(1) := false.B }
-    } .elsewhen(
-      io.enq.bits.isLast ||
-      (if( threshold != 0 ) {recCnt === threshold.U } else {false.B})
-      ){
-      when( isEnqPi ){ isReach(0) := true.B }
-      when( isEnqPo ){ isReach(1) := true.B }
-    }
-  }
-
-
-
-}
-
-trait RxBuffDeq{ this: RxBuffBase =>
-
-  when( io.header.fire ){
-    when( isDeqPi ) { hValid(0) := false.B }
-    when( isDeqPo ) { hValid(1) := false.B }
-  } .elsewhen( io.enq.fire & recCnt === 20.U ){
-    when( isEnqPi ) { hValid(0) := true.B }
-    when( isEnqPo ) { hValid(1) := true.B }
-  }
-
-
-  when( io.deq.fire & io.deq.bits.isLast ){
-    isDeqPi := ~isDeqPi
-  }
-
-
-  when( isDeqPi ){
-    io.deq.valid := buff(0).io.deq.valid & isReach(0)
-    io.deq.bits  := buff(0).io.deq.bits
-    buff(0).io.deq.ready := io.deq.ready & isReach(0)
-
-    buff(1).io.deq.ready := false.B
-
-    io.header.valid := hValid(0)
-    io.header.bits  := header(0)
-  } .otherwise{
-    assert( isDeqPo )
-    io.deq.valid := buff(1).io.deq.valid & isReach(1)
-    io.deq.bits  := buff(1).io.deq.bits
-    buff(1).io.deq.ready := io.deq.ready & isReach(1)
-
-    buff(0).io.deq.ready := false.B
-
-    io.header.valid := hValid(1)
-    io.header.bits  := header(1)
-  }
-
-
-
-}
-
-
-class RxBuff(threshold: Int = 8) extends RxBuffBase(threshold) with RxBuffEnq with RxBuffDeq{
-
-}
-
diff --git a/src/main/scala/Switch/SwitchNode.scala b/src/main/scala/Switch/SwitchNode.scala
index a3337f9..b105bbd 100644
--- a/src/main/scala/Switch/SwitchNode.scala
+++ b/src/main/scala/Switch/SwitchNode.scala
@@ -35,7 +35,7 @@ class MacNode(implicit p: Parameters) extends Mac{
   val rxBuff = Module(new RxBuff)
   val txBuff = Module(new TxBuff)
 
-  rxBuff.io.header.ready := true.B
+  rxBuff.headerIO.ready := true.B
 
   macTileLinkRx.io.rxEnq <> rxBuff.io.enq
   txBuff.io.deq <> macTileLinkTx.io.txDeq
diff --git a/src/main/scala/Switch/TxBuff.scala b/src/main/scala/Switch/TxBuff.scala.bk
similarity index 92%
rename from src/main/scala/Switch/TxBuff.scala
rename to src/main/scala/Switch/TxBuff.scala.bk
index d4e1830..d018398 100644
--- a/src/main/scala/Switch/TxBuff.scala
+++ b/src/main/scala/Switch/TxBuff.scala.bk
@@ -65,4 +65,4 @@ trait TxBuffDeq{ this: TxBuffBase =>
 }
 
 
-class TxBuff(threshold: Int = 8) extends TxBuffBase(threshold) with TxBuffEnq with TxBuffDeq
+