From 9f9f7a8de591b09708ac81b0d41ffb2ef57f53bf Mon Sep 17 00:00:00 2001
From: BlackMark <me@blackmark.me>
Date: Sat, 3 Aug 2019 17:52:28 +0200
Subject: [PATCH] Added flushing of transmit buffer

---
 hardware.hpp  |  7 ++++++-
 hardware0.hpp | 14 ++++++++++++++
 hardware1.hpp | 14 ++++++++++++++
 uart.hpp      |  5 +++++
 4 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/hardware.hpp b/hardware.hpp
index 37100a0..aef1724 100644
--- a/hardware.hpp
+++ b/hardware.hpp
@@ -64,9 +64,14 @@ class Hardware {
 		return *Registers::IO_REG;
 	}
 
+	static bool txActive() FORCE_INLINE
+	{
+		return !(*Registers::CTRL_STAT_REG_A & (1 << CtrlFlagsA::DATA_REG_EMPTY));
+	}
+
 	static void txByteBlocking(const typename cfg::data_t &byte) FORCE_INLINE
 	{
-		while (!(*Registers::CTRL_STAT_REG_A & (1 << CtrlFlagsA::DATA_REG_EMPTY)))
+		while (txActive())
 			;
 
 		*Registers::IO_REG = byte;
diff --git a/hardware0.hpp b/hardware0.hpp
index 8ce0629..7c36201 100644
--- a/hardware0.hpp
+++ b/hardware0.hpp
@@ -105,6 +105,12 @@ class Hardware0 {
 		return HardwareImpl::peekBlocking();
 	}
 
+	static void flushTx() FORCE_INLINE
+	{
+		while (HardwareImpl::txActive())
+			;
+	}
+
   private:
 	using HardwareImpl = detail::Hardware<detail::Registers0, detail::ControlFlagsA0, detail::ControlFlagsB0,
 	                                      detail::ControlFlagsC0, cfg, mode, driven>;
@@ -164,6 +170,14 @@ class Hardware0<mode, cfg, Driven::INTERRUPT> {
 		return (sm_rxBuf.head != sm_rxBuf.tail);
 	}
 
+	static void flushTx() FORCE_INLINE
+	{
+		while (sm_txBuf.head != sm_txBuf.tail)
+			;
+		while (HardwareImpl::txActive())
+			;
+	}
+
   private:
 	using HardwareImpl = detail::Hardware<detail::Registers0, detail::ControlFlagsA0, detail::ControlFlagsB0,
 	                                      detail::ControlFlagsC0, cfg, mode, Driven::INTERRUPT>;
diff --git a/hardware1.hpp b/hardware1.hpp
index 5528b32..06deeaf 100644
--- a/hardware1.hpp
+++ b/hardware1.hpp
@@ -109,6 +109,12 @@ class Hardware1 {
 		return HardwareImpl::peekBlocking();
 	}
 
+	static void flushTx() FORCE_INLINE
+	{
+		while (HardwareImpl::txActive())
+			;
+	}
+
   private:
 	using HardwareImpl = detail::Hardware<detail::Registers1, detail::ControlFlagsA1, detail::ControlFlagsB1,
 	                                      detail::ControlFlagsC1, cfg, mode, driven>;
@@ -168,6 +174,14 @@ class Hardware1<mode, cfg, Driven::INTERRUPT> {
 		return (sm_rxBuf.head != sm_rxBuf.tail);
 	}
 
+	static void flushTx() FORCE_INLINE
+	{
+		while (sm_txBuf.head != sm_txBuf.tail)
+			;
+		while (HardwareImpl::txActive())
+			;
+	}
+
   private:
 	using HardwareImpl = detail::Hardware<detail::Registers1, detail::ControlFlagsA1, detail::ControlFlagsB1,
 	                                      detail::ControlFlagsC1, cfg, mode, Driven::INTERRUPT>;
diff --git a/uart.hpp b/uart.hpp
index e87124d..91326ab 100644
--- a/uart.hpp
+++ b/uart.hpp
@@ -88,6 +88,11 @@ class Uart {
 		return Driver::peek();
 	}
 
+	static void flushTx()
+	{
+		Driver::flushTx();
+	}
+
 	static void txString(const char *str)
 	{
 		static_assert(Driver::DATA_BITS == DataBits::EIGHT, "Strings are only supported with 8 data bits");