From 09b2823ef624469e258db1e5309f3cc63c9ea1a9 Mon Sep 17 00:00:00 2001
From: MadMaurice <madmaurice@zom.bi>
Date: Wed, 30 Aug 2023 22:16:57 +0200
Subject: [PATCH] memory - Add way to map register into address space

---
 Makeconf            |  1 +
 memory/register.cpp | 13 +++++++++++++
 memory/register.h   | 17 +++++++++++++++++
 3 files changed, 31 insertions(+)
 create mode 100644 memory/register.cpp
 create mode 100644 memory/register.h

diff --git a/Makeconf b/Makeconf
index 73b4f2c..695f9ca 100644
--- a/Makeconf
+++ b/Makeconf
@@ -2,6 +2,7 @@ modules := memory/mem_device \
            memory/bus \
            memory/ram \
            memory/bootrom_overlay \
+           memory/register \
            cpu/cpu \
            cpu/decoder
 
diff --git a/memory/register.cpp b/memory/register.cpp
new file mode 100644
index 0000000..2dcc64d
--- /dev/null
+++ b/memory/register.cpp
@@ -0,0 +1,13 @@
+#include <memory/register.h>
+
+void BoundRegister::write8(u16 addr, u8 data)
+{
+  if(addr) return;
+  reg = data;
+}
+
+u8 BoundRegister::read8(u16 addr)
+{
+  if(addr) return 0xFF;
+  return reg;
+}
diff --git a/memory/register.h b/memory/register.h
new file mode 100644
index 0000000..92aef64
--- /dev/null
+++ b/memory/register.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <misc/types.h>
+#include <memory/mem_device.h>
+
+class BoundRegister : public Mem_device {
+private:
+  u8& reg;
+public:
+  inline
+  BoundRegister(u8& reg)
+    : reg(reg)
+  {}
+
+  virtual void write8(u16 addr, u8 data);
+  virtual u8 read8(u16 addr);
+};