From 351becc03c6649fd6f1846c57444425ed63dc768 Mon Sep 17 00:00:00 2001
From: t-wallet <tw.personal@tutanota.com>
Date: Fri, 8 Mar 2024 14:24:47 +0100
Subject: [PATCH] component now handles backpressure and changed definition to
 return a Circuit

---
 src/Clash/Lattice/ECP5/UART.hs | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/src/Clash/Lattice/ECP5/UART.hs b/src/Clash/Lattice/ECP5/UART.hs
index 8b586ae2..f9855637 100644
--- a/src/Clash/Lattice/ECP5/UART.hs
+++ b/src/Clash/Lattice/ECP5/UART.hs
@@ -1,26 +1,31 @@
 {-#language FlexibleContexts #-}
 
-module Clash.Lattice.ECP5.UART (uartTx') where
+module Clash.Lattice.ECP5.UART
+    (uartTxC) where
 
 import Data.Maybe
-import Clash.Cores.Ethernet.PacketStream
+
 import Clash.Prelude
-import Protocols
+import Clash.Cores.Ethernet.PacketStream
 import Clash.Cores.UART
+import Protocols
+import Protocols.Internal
+
 
-convert :: Fwd (PacketStream dom 1 ()) -> Signal dom (Maybe (BitVector 8))
-convert = fmap $ fmap $ (head . _data)
+convertToTx :: Signal dom (Maybe (PacketStreamM2S 1 ())) -> Signal dom (Maybe (BitVector 8))
+convertToTx = fmap $ fmap $ (head . _data)
 
-uartTx'
+uartTxC
   :: forall (dom :: Domain)
             (baud :: Nat)
    . HiddenClockResetEnable dom
   => ValidBaud dom baud
   => SNat baud
   -- ^ The UART baud
-  -> Signal dom (Maybe (PacketStreamM2S 1 ()))
-  -- ^ The word to transmit
-  -> (Signal dom Bit, Signal dom Bool)
-  -- ^ The output bits for the tx line and an acknowledgement that the word
-  -- to transmit has been received
-uartTx' baud mWord = uartTx baud (convert mWord)
+  -> Circuit (PacketStream dom 1 ()) (CSignal dom Bit)
+  -- ^ This component receives a PacketStream and converts it to the UART transmitter input while relaying backpressure from the UART
+uartTxC baud = fromSignals ckt
+  where
+    ckt (fwd, _) =  (PacketStreamS2M <$> ack, CSignal txBit)
+      where
+        (txBit, ack) = uartTx baud (convertToTx fwd)