Finish UartDebug

Author: schoeberl

7series.txt

@@ -18,5 +18,5 @@ puts [irscan xc7.tap 0x09]
 puts [drscan xc7.tap 32 0]  
 
 puts "Programming FPGA..."
-pld load 0 build/BitBang.bit
+pld load 0 build/UartDebug.bit
 exit

src/main/scala/debug/UartDebug.scala

@@ -15,20 +15,147 @@ class UartDebug(frequ: Int, baudRate: Int = 115200) extends Module {
     val din = Input(UInt(32.W))
   })
 
+  // ASCII -> hex including valid signal
+  def ascii2hex(in: UInt) = {
+    val out = Wire(UInt(8.W))
+    val valid = false.B
+    out := 16.U
+    switch(in) {
+      is('0'.U) { out := "h0".U }
+      is('1'.U) { out := "h1".U }
+      is('2'.U) { out := "h2".U }
+      is('3'.U) { out := "h3".U }
+      is('4'.U) { out := "h4".U }
+      is('5'.U) { out := "h5".U }
+      is('6'.U) { out := "h6".U }
+      is('7'.U) { out := "h7".U }
+      is('8'.U) { out := "h8".U }
+      is('9'.U) { out := "h9".U }
+      is('a'.U) { out := "ha".U }
+      is('b'.U) { out := "hb".U }
+      is('c'.U) { out := "hc".U }
+      is('d'.U) { out := "hd".U }
+      is('e'.U) { out := "he".U }
+      is('f'.U) { out := "hf".U }
+      is('A'.U) { out := "hA".U }
+      is('B'.U) { out := "hB".U }
+      is('C'.U) { out := "hC".U }
+      is('D'.U) { out := "hD".U }
+      is('E'.U) { out := "hE".U }
+      is('F'.U) { out := "hF".U }
+    }
+    (out(3, 0), out =/= 16.U)
+  }
+
+  def hex2ascii(in: UInt) = {
+    val out = Wire(UInt(8.W))
+    out := 0.U
+    switch(in) {
+      is("h0".U) { out := '0'.U }
+      is("h1".U) { out := '1'.U }
+      is("h2".U) { out := '2'.U }
+      is("h3".U) { out := '3'.U }
+      is("h4".U) { out := '4'.U }
+      is("h5".U) { out := '5'.U }
+      is("h6".U) { out := '6'.U }
+      is("h7".U) { out := '7'.U }
+      is("h8".U) { out := '8'.U }
+      is("h9".U) { out := '9'.U }
+      is("ha".U) { out := 'a'.U }
+      is("hb".U) { out := 'b'.U }
+      is("hc".U) { out := 'c'.U }
+      is("hd".U) { out := 'd'.U }
+      is("he".U) { out := 'e'.U }
+      is("hf".U) { out := 'f'.U }
+    }
+    out
+  }
+
   val tx = Module(new BufferedTx(100000000, baudRate))
   val rx = Module(new Rx(100000000, baudRate))
 
   io.tx := tx.io.txd
   rx.io.rxd := io.rx
 
-  tx.io.channel.bits := rx.io.channel.bits + 1.U
-  tx.io.channel.valid := rx.io.channel.valid
-  rx.io.channel.ready := tx.io.channel.ready
+  val inReg = RegInit(0.U(8.W))
+  val validReg = RegInit(false.B)
+
+  rx.io.channel.ready := true.B
+  when (rx.io.channel.valid) {
+    inReg := rx.io.channel.bits
+    validReg := true.B
+  }
+
+  tx.io.channel.bits := inReg
+  tx.io.channel.valid := false.B
+
+  when (tx.io.channel.ready && validReg) {
+    validReg := false.B
+    tx.io.channel.valid := true.B
+  }
+
+  val doutReg = RegInit(0x1234.U(32.W))
+  val doutShftReg = RegInit(0.U(32.W))
+  val dinShftReg = RegInit(0.U(32.W))
+  val cntRdReg = RegInit(0.U(4.W))
+
+  object State extends ChiselEnum {
+    val sIdle, sLineFeed, sWrite, sRead, sCr = Value
+  }
+  import State._
+  val stateReg = RegInit(sIdle)
 
-  io.dout := 0x1234.U
-  when (tx.io.channel.valid && tx.io.channel.ready) {
-    io.dout := tx.io.channel.bits
+  switch(stateReg) {
+    is(sIdle) {
+      when (validReg && inReg === 'w'.U) {
+        stateReg := sWrite
+        doutShftReg := 0.U
+      }
+      when (validReg && inReg === 'r'.U) {
+        stateReg := sRead
+        dinShftReg := io.din
+        cntRdReg := 8.U
+      }
+    }
+    is(sWrite) {
+      when (validReg) {
+        when (inReg === '\r'.U) {
+          stateReg := sLineFeed
+          doutReg := doutShftReg
+        }
+        val (out, valid) = ascii2hex(inReg)
+        when (valid) {
+          doutShftReg := doutShftReg(31, 8)
+          doutShftReg := doutShftReg ## out
+        }
+      }
+    }
+    is(sLineFeed) {
+      tx.io.channel.valid := true.B
+      tx.io.channel.bits := '\n'.U
+      when (tx.io.channel.ready) {
+        stateReg := sIdle
+      }
+    }
+    is(sRead) {
+      when (cntRdReg =/= 0.U) {
+        tx.io.channel.valid := true.B
+        tx.io.channel.bits := hex2ascii(dinShftReg(31, 28))
+        when (tx.io.channel.ready) {
+          dinShftReg := dinShftReg << 4
+          cntRdReg := cntRdReg - 1.U
+        }
+      }
+      when (cntRdReg === 0.U) {
+        tx.io.channel.valid := true.B
+        tx.io.channel.bits := '\r'.U
+        when (tx.io.channel.ready) {
+          stateReg := sLineFeed
+        }
+      }
+    }
   }
+  io.dout := doutReg
 }
 
 object UartDebug extends App {

src/test/scala/debug/UartDebugTest.scala

@@ -10,8 +10,8 @@ class UartDebugTestTop extends Module {
   val io = IO(new Bundle {
     val inRx = new UartIO()
     val outTx = Flipped(new UartIO())
-    val dout = Output(UInt(32.W))
-    val din = Input(UInt(32.W))
+    // val dout = Output(UInt(32.W))
+    // val din = Input(UInt(32.W))
   })
 
   val tx = Module(new BufferedTx(100000000, 100000000/16))
@@ -24,20 +24,29 @@ class UartDebugTestTop extends Module {
 
   dbg.io.rx := tx.io.txd
   rx.io.rxd := dbg.io.tx
-  io.dout := dbg.io.dout
-  dbg.io.din := io.din
+  dbg.io.din := ~dbg.io.dout
 }
 
 class UartDebugTest extends AnyFlatSpec with ChiselScalatestTester {
   "UartDebug" should "work" in {
     test(new UartDebugTestTop()).withAnnotations(Seq(WriteVcdAnnotation)) { dut =>
-      dut.io.din.poke(0xabcd.U)
-      dut.clock.setTimeout(10001)
-      dut.io.outTx.valid.poke(true.B)
-      dut.io.outTx.bits.poke(0x42.U)
-      dut.clock.step(10)
-      dut.io.outTx.valid.poke(false.B)
-      dut.clock.step(1000)
+      def write(c: Char): Unit = {
+        dut.io.outTx.valid.poke(true.B)
+        dut.io.outTx.bits.poke(c.U)
+        while (!dut.io.outTx.ready.peekBoolean()) {
+          dut.clock.step(1)
+        }
+        dut.clock.step(1)
+        dut.io.outTx.valid.poke(false.B)
+      }
+
+      val s = "w123xabc\r r "
+      for (c <- s) {
+        write(c)
+      }
+      dut.clock.setTimeout(0)
+      // TODO: real checks would be nice, not jst waveform inspection
+      dut.clock.step(5000)
     }
   }
 }