From dca2e1bb8eda2d74bfb0a080dc85b4a31d11f0a2 Mon Sep 17 00:00:00 2001
From: Adrian Conlon <Adrian.conlon@gmail.com>
Date: Sun, 2 Jun 2019 12:12:04 +0100
Subject: [PATCH] Bring the C++ code a little closer to the C# code.

Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
---
 M6532/src/M6532.cpp   |   2 +-
 MC6809/test/Board.cpp |   8 ++++----
 MC6850/inc/MC6850.h   |   2 +-
 MC6850/src/MC6850.cpp | Bin 8042 -> 7808 bytes
 inc/Device.h          |   8 ++++++++
 5 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/M6532/src/M6532.cpp b/M6532/src/M6532.cpp
index 35d5aef..ab2dc55 100644
--- a/M6532/src/M6532.cpp
+++ b/M6532/src/M6532.cpp
@@ -44,7 +44,7 @@ void EightBit::M6532::step() {
 	if (interruptTimer)
 		setFlag(IF(), Bit7);
 
-	interruptPA7 || interruptTimer ? lower(IRQ()) : raise(IRQ());
+	match(IRQ(), !(interruptPA7 || interruptTimer));
 
 	const auto read = raised(RW());
 	const auto write = lowered(RW());
diff --git a/MC6809/test/Board.cpp b/MC6809/test/Board.cpp
index 16e976c..ab49b05 100644
--- a/MC6809/test/Board.cpp
+++ b/MC6809/test/Board.cpp
@@ -113,10 +113,10 @@ EightBit::MemoryMapping Board::mapping(uint16_t address) {
 
 void Board::updateAciaPins() {
 	ACIA().DATA() = DATA();
-	ADDRESS().word & EightBit::Chip::Bit0 ? ACIA().raise(ACIA().RS()) : ACIA().lower(ACIA().RS());
-	ADDRESS().word & EightBit::Chip::Bit15 ? ACIA().raise(ACIA().CS0()) : ACIA().lower(ACIA().CS0());
-	ADDRESS().word & EightBit::Chip::Bit13 ? ACIA().raise(ACIA().CS1()) : ACIA().lower(ACIA().CS1());
-	ADDRESS().word & EightBit::Chip::Bit14 ? ACIA().raise(ACIA().CS2()) : ACIA().lower(ACIA().CS2());
+	EightBit::Device::match(ACIA().RS(), ADDRESS().word & EightBit::Chip::Bit0);
+	EightBit::Device::match(ACIA().CS0(), ADDRESS().word & EightBit::Chip::Bit15);
+	EightBit::Device::match(ACIA().CS1(), ADDRESS().word & EightBit::Chip::Bit13);
+	EightBit::Device::match(ACIA().CS2(), ADDRESS().word & EightBit::Chip::Bit14);
 }
 
 bool Board::accessAcia() {
diff --git a/MC6850/inc/MC6850.h b/MC6850/inc/MC6850.h
index 47f2e02..a5f7c08 100644
--- a/MC6850/inc/MC6850.h
+++ b/MC6850/inc/MC6850.h
@@ -205,7 +205,7 @@ namespace EightBit {
 		auto& RDR() { return m_RDR; }
 
 		bool activated() { return powered() && raised(E()) && selected(); }
-		bool selected();
+		bool selected() { return raised(CS0()) && raised(CS1()) && lowered(CS2()); }
 
 		void markTransmitComplete();
 		void markReceiveStarting();
diff --git a/MC6850/src/MC6850.cpp b/MC6850/src/MC6850.cpp
index 86d68b33929d45f646805a54be8317732b66ad64..c48ef131137ce1e3e51a5caf9e034ace11dec294 100644
GIT binary patch
delta 51
zcmaE5*I>Kh3hU$_QhJ-uux(?P%w<SqC}Buu$Y9W52x16f2nN!c3_1)7lN<TeH$UR*
G5C8zb4i4-9

delta 197
zcmZp$ePy@d3M+dOLp~7ZOr9vAE?&%#%8&!Z$qXexGKE2dL6bp&p?Y$lsBoeJLlHwF
zLnZ@A4M@hBA(+7ctOBG)4G6KRFho<41GK9gXhIQ^DMk=AlM6ZQH#4zqW1oD9SB+JH
g!Ja{3vLm~sxB`O}&}f844Td0w5QgB*pLu%)01=5LkpKVy

diff --git a/inc/Device.h b/inc/Device.h
index 1937a83..f027155 100644
--- a/inc/Device.h
+++ b/inc/Device.h
@@ -64,6 +64,14 @@ namespace EightBit {
 		static constexpr auto lowered(const PinLevel line) { return line == PinLevel::Low; }
 		static void lower(PinLevel& line) noexcept { line = PinLevel::Low; }
 
+		static void match(PinLevel& line, int condition) {
+			match(line, condition != 0);
+		}
+
+		static void match(PinLevel& line, bool condition) {
+			condition ? raise(line) : lower(line);
+		}
+
 		virtual ~Device() {};
 
 		[[nodiscard]] bool powered() noexcept { return raised(POWER()); }