建立从站状态机

src/main/scala/backBoard/shin/SlaveParser.scala

@@ -4,16 +4,87 @@ import chisel3._
 import chisel3.util._
 
 class SlaveParserIO extends Module{
+  val downOut = Decoupled(new AXIS_Bundle(8))
+  val downIn  = Flipped( Decoupled(new AXIS_Bundle(8)) )
 
+  val upOut = Decoupled(new AXIS_Bundle(8))
+  val upIn  = Flipped( Decoupled(new AXIS_Bundle(8)) )
+
+  val sram
 }
 
 abstract class SlaveParserBase extends Module{
   val io: SlaveParserIO = IO(new SlaveParserIO)
 
+  val FRAME_STYLE_COMMON = 0.U
+  val FRAME_STYLE_PROBE  = 1.U
 
+
+  val STATE_IDLE            = 0.U //空闲
+  val STATE_HEADER          = 1.U //长度/ /保留2bits //包类型
+  val STATE_PAYLOAD_INDEX_STYLE   = 4.U //子报文设备索引 //子报文类型
+  val STATE_PAYLOAD_ADDR    = 6.U //子报文地址
+  val STATE_PAYLOAD_OP_LENGTH   = 7.U //子报文命令类型 //子报文长度
+  val STATE_PAYLOAD_WORKCNT = 9.U //子报文工作计数
+  val STATE_PAYLOAD_DATA    = 10.U //子报文数据
+  val STATE_CRC             = 11.U //CRC校验
+  val STATE_ERROR           = 12.U //
+
+
+  val downStateNext = Wire(UInt(4.W))
+  val downStateCurr = RegNext(downStateNext, STATE_IDLE(4.W))
+
+  val lengthCnt = Reg(UInt(11.W)) //动态计数器
+  val subMsgCnt = Reg(UInt(7.W)) //子报文不超过64个？
+  val subMsgLenAim = Reg(UInt(11.W)) //子报文长度
+  val FrameLenAim  = Reg(UInt(11.W)) //帧长度目标
+  val FrameLenCnt  = Reg(UInt(11.W)) //帧长度计数
+  val isCrcPass: Bool
+  val isTxEnd: Bool
+  val isShortRx: Bool //接收长度小于预期
+
+  downStateNext := 
+    Mux1H(Seq(
+                                                        //必须使用上升沿触发，以避免前一帧长度超过预期
+      ( downStateCurr === STATE_IDLE                ) -> Mux( ~RegNext(io.downIn.axis.valid) & io.downIn.axis.valid, STATE_HEADER, STATE_IDLE ), 
+      ( downStateCurr === STATE_HEADER              ) -> Mux( isShortRx, STATE_ERROR,
+          MuxCase( STATE_ERROR, Array(
+            ( io.downIn.axis.bits(1,0) === FRAME_STYLE_COMMON ) -> STATE_PAYLOAD_INDEX_STYLE,
+            ( io.downIn.axis.bits(1,0) === FRAME_STYLE_PROBE  ) -> STATE_CRC,
+          ))
+        ),
+      ( downStateCurr === STATE_PAYLOAD_INDEX_STYLE ) -> Mux( isShortRx, STATE_ERROR,
+          STATE_PAYLOAD_ADDR
+        ),
+      ( downStateCurr === STATE_PAYLOAD_ADDR        ) -> Mux( isShortRx,
+          STATE_PAYLOAD_OP_LENGTH
+        ),
+      ( downStateCurr === STATE_PAYLOAD_OP_LENGTH   ) -> Mux( isShortRx,
+          STATE_PAYLOAD_WORKCNT
+        ),
+      ( downStateCurr === STATE_PAYLOAD_WORKCNT     ) -> Mux( isShortRx,
+          Mux( lengthCnt === (2 - 1).U, STATE_PAYLOAD_DATA, STATE_PAYLOAD_WORKCNT )
+        ),
+      ( downStateCurr === STATE_PAYLOAD_DATA        ) -> Mux( isShortRx, 
+          Mux( lengthCnt === (subMsgLen - 1.U), 
+            Mux(FrameLenCnt === FrameLenAim, STATE_CRC, STATE_PAYLOAD_INDEX_STYLE
+          ), STATE_PAYLOAD_DATA )
+        ),
+      ( downStateCurr === STATE_CRC                 ) -> Mux( isShortRx, 
+          Mux( lengthCnt === (4 - 1).U, Mux( isCrcPass, STATE_IDLE, STATE_ERROR), STATE_CRC )
+        ),
+      ( downStateCurr === STATE_ERROR               ) -> Mux( isTxEnd, STATE_IDLE, STATE_ERROR ), 
+    ))
+
+  // assert( ~(downStateCurr === STATE_HEADER              & ~io.downIn.axis.fire), "Assert Failed!" )
+  // assert( ~(downStateCurr === STATE_PAYLOAD_INDEX_STYLE & ~io.downIn.axis.fire), "Assert Failed!" )
+  // assert( ~(downStateCurr === STATE_PAYLOAD_ADDR        & ~io.downIn.axis.fire), "Assert Failed!" )
 }
 
 
+
+
+
 class SlaveParser extends SlaveParserBase{
 
 }