diff --git a/doc/spec/物理层优化.md b/doc/spec/物理层优化.md
index eeabb5f..97434ff 100644
--- a/doc/spec/物理层优化.md
+++ b/doc/spec/物理层优化.md
@@ -48,6 +48,11 @@
     - 上行relay在`isProbeAck`跳变状态直接拷贝下行寄存器信息，其它条件看上行输入的6个`isK`布尔信号直接转译8bit原始码
 
 
+* 上下行清硬件错误的条件增加为**上**行接收到`isK28_0`
+* 从站发生硬件错误时，软件先写`clr`寄存器预解锁，其后上行方向接收到K28_0完成正式解锁
+* 预解锁需要在K28_0之前，两者在同一拍到达将只会产生预解锁效果
+
+
 ---------------------------------------
 
 以下是大模型补充区域
diff --git a/src/main/scala/backBoard/shin/MstSlvSwitch.scala b/src/main/scala/backBoard/shin/MstSlvSwitch.scala
index 1a0aa69..2b52960 100644
--- a/src/main/scala/backBoard/shin/MstSlvSwitch.scala
+++ b/src/main/scala/backBoard/shin/MstSlvSwitch.scala
@@ -435,12 +435,28 @@ trait MstSlvSwitchSlave{ this: MstSlvSwitchBase =>
 
   }
 
-  slaveParser.io.intHWClr(0) := interface.io.intHWTrig(0) & interface.io.intHWClr(0)
-  slaveParser.io.intHWClr(1) := interface.io.intHWTrig(1) & interface.io.intHWClr(1)
-  downCDRInAxis.io.flush  := RegNext( interface.io.intHWTrig(0) & interface.io.intHWClr(0), false.B )
-  upCDRInAxis.io.flush    := RegNext( interface.io.intHWTrig(1) & interface.io.intHWClr(1), false.B )
-  downCDROut.io.flush := RegNext( interface.io.intHWTrig(0) & interface.io.intHWClr(0), false.B )
-  upCDROut.io.flush   := RegNext( interface.io.intHWTrig(1) & interface.io.intHWClr(1), false.B )
+  val intHWClr = for( _ <- 0 until 2) yield Wire(Bool())
+  val intHWClrCMDRev = for( _ <- 0 until 2) yield RegInit(false.B)
+
+  for( i <- 0 until 2 ){
+    when( interface.io.intHWTrig(i) & interface.io.intHWClr(i) ){
+      intHWClrCMDRev(i) := true.B
+    } .elsewhen( upCDRInAxis.io.isK28_0 ){
+      intHWClrCMDRev(i) := false.B
+    }
+
+    intHWClr(i) := intHWClrCMDRev(i) & upCDRInAxis.io.isK28_0
+  }
+
+
+
+
+  slaveParser.io.intHWClr(0) := intHWClr(0)
+  slaveParser.io.intHWClr(1) := intHWClr(1)
+  downCDRInAxis.io.flush  := RegNext( intHWClr(0), false.B )
+  upCDRInAxis.io.flush    := RegNext( intHWClr(1), false.B )
+  downCDROut.io.flush := RegNext( intHWClr(0), false.B )
+  upCDROut.io.flush   := RegNext( intHWClr(1), false.B )
 
   interface.io.lvds <> slaveParser.io.lvds