From 4f567c75f939a1ea4f622adfed7f3813569ea7aa Mon Sep 17 00:00:00 2001
From: Adrian Conlon <Adrian.conlon@gmail.com>
Date: Tue, 25 Sep 2018 23:55:14 +0100
Subject: [PATCH] Probably doesn't work, but this is another style of MC6850
 event handling

Signed-off-by: Adrian Conlon <Adrian.conlon@gmail.com>
---
 MC6850/inc/MC6850.h   |  36 ++++++++++++++++++++----------------
 MC6850/src/MC6850.cpp | Bin 3490 -> 5026 bytes
 2 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/MC6850/inc/MC6850.h b/MC6850/inc/MC6850.h
index 88637df..2055f90 100644
--- a/MC6850/inc/MC6850.h
+++ b/MC6850/inc/MC6850.h
@@ -60,14 +60,14 @@ namespace EightBit {
 		};
 		
 		enum StatusRegisters {
-			RDRF	= 0b1,
-			TDRE	= 0b10,
-			kDCD	= 0b100,
-			kCTS	= 0b1000,
-			FE		= 0b10000,
-			OVRN	= 0b100000,
-			PE		= 0b1000000,
-			kIRQ	= 0b10000000,
+			STATUS_RDRF	= 0b1,
+			STATUS_TDRE	= 0b10,
+			STATUS_DCD	= 0b100,
+			STATUS_CTS	= 0b1000,
+			STATUS_FE	= 0b10000,
+			STATUS_OVRN	= 0b100000,
+			STATUS_PE	= 0b1000000,
+			STATUS_IRQ	= 0b10000000,
 		};
 
 		PinLevel& RXDATA() { return m_RXDATA; }	// Receive data, (I) Active high
@@ -93,10 +93,14 @@ namespace EightBit {
 
 		uint8_t& DATA() { return m_data; }		// Data, (I/O)
 
+		// Expose these internal registers, so we can update internal state
+		uint8_t& TDR() { return m_TDR; }		// Transmit data register;
+		uint8_t& RDR() { return m_RDR; }		// Receive data register;
+
 		void step(int cycles);
 
-		void fillRDR();
-		void drainTDR();
+		void markTransmitComplete();
+		void markReceiveStarting();
 
 		Signal<EventArgs> Accessing;
 		Signal<EventArgs> Accessed;
@@ -108,9 +112,6 @@ namespace EightBit {
 		Signal<EventArgs> Received;
 
 	private:
-		uint8_t& TDR() { return m_TDR; }	// Transmit data register;
-		uint8_t& RDR() { return m_RDR; }	// Receive data register;
-
 		uint8_t& status() { return m_status; }
 
 		bool selected();
@@ -119,8 +120,11 @@ namespace EightBit {
 
 		void step();
 
-		void drainRDR();
-		void fillTDR();
+		void startTransmit();
+		void markTransmitStarting();
+
+		void completeReceive();
+		void markReceiveComplete();
 
 		PinLevel m_RXDATA;
 		PinLevel m_TXDATA;
@@ -147,7 +151,7 @@ namespace EightBit {
 		// Control registers
 		int m_counterDivide;
 		int m_wordConfiguration;
-		int m_transmitterControl;
+		int m_transmitControl;
 		int m_receiveControl;
 
 		// Status registers
diff --git a/MC6850/src/MC6850.cpp b/MC6850/src/MC6850.cpp
index e4a7b175c420769de0fdb6a59289342596a16b8f..c94d5411909a159764ec294cceb18faacdab868d 100644
GIT binary patch
delta 1113
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delta 224
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