From 7948962d70abb04f25685ecd1bca04f2babd6a3c Mon Sep 17 00:00:00 2001
From: "Adrian.Conlon" <adrian.conlon@gmail.com>
Date: Thu, 10 Aug 2017 20:30:37 +0100
Subject: [PATCH] Because of its boot room, the LR35902 needs a custom clear
 mechanism.

Signed-off-by: Adrian.Conlon <adrian.conlon@gmail.com>
---
 LR35902/inc/Bus.h   | 8 +++++++-
 LR35902/src/Bus.cpp | 8 +++++++-
 inc/Memory.h        | 2 +-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/LR35902/inc/Bus.h b/LR35902/inc/Bus.h
index e1c956b..9646053 100644
--- a/LR35902/inc/Bus.h
+++ b/LR35902/inc/Bus.h
@@ -79,6 +79,8 @@ namespace EightBit {
 
 		void reset();
 
+		virtual void clear() override;
+
 		void writeRegister(int offset, uint8_t content) {
 			return Memory::write(BASE + offset, content);
 		}
@@ -95,10 +97,13 @@ namespace EightBit {
 			writeRegister(LY, 0);
 		}
 
+		void disableBootRom() { m_disableBootRom = true; }
+		void enableBootRom() { m_disableBootRom = false; }
+
 		void loadBootRom(const std::string& path);
 
 		bool isBootRom(uint16_t address) const {
-			return (address < m_boot.size()) && !peek(BASE + BOOT_DISABLE);
+			return !m_disableBootRom && (address < m_boot.size()) && !peek(BASE + BOOT_DISABLE);
 		}
 
 		virtual uint8_t peek(uint16_t address) const;
@@ -107,5 +112,6 @@ namespace EightBit {
 
 	private:
 		std::array<uint8_t, 0x100> m_boot;
+		bool m_disableBootRom;
 	};
 }
\ No newline at end of file
diff --git a/LR35902/src/Bus.cpp b/LR35902/src/Bus.cpp
index b56cdd2..b5cd1de 100644
--- a/LR35902/src/Bus.cpp
+++ b/LR35902/src/Bus.cpp
@@ -2,7 +2,8 @@
 #include "Bus.h"
 
 EightBit::Bus::Bus()
-: Memory(0xffff) {
+: Memory(0xffff),
+  m_disableBootRom(false) {
 }
 
 void EightBit::Bus::reset() {
@@ -10,6 +11,11 @@ void EightBit::Bus::reset() {
 	writeRegister(LCDC, 0x91);
 }
 
+void EightBit::Bus::clear() {
+	Memory::clear();
+	m_boot.fill(0);
+}
+
 void EightBit::Bus::loadBootRom(const std::string& path) {
 	auto size = loadMemory(path, 0);
 	if (size != 0x100)
diff --git a/inc/Memory.h b/inc/Memory.h
index 90dd4d7..8da332b 100644
--- a/inc/Memory.h
+++ b/inc/Memory.h
@@ -91,7 +91,7 @@ namespace EightBit {
 			write(value);
 		}
 
-		void clear();
+		virtual void clear();
 		void loadRom(const std::string& path, uint16_t offset);
 		void loadRam(const std::string& path, uint16_t offset);