--- nono/vm/sram.h	2026/04/29 17:04:53	1.1.1.6
+++ nono/vm/sram.h	2026/04/29 17:05:24	1.1.1.11
@@ -4,16 +4,20 @@
 // Licensed under nono-license.txt
 //
 
+//
+// SRAM
+//
+
 #pragma once
 
 #include "device.h"
 #include "mappedfile.h"
+#include <array>
 
-class SRAMDevice
-	: public IODevice
+class SRAMDevice : public IODevice
 {
 	using inherited = IODevice;
- private:
+
 	static const uint32 baseaddr = 0xed0000;
 
 	// Pluto-X によるホストファイル起動アドレス
@@ -21,22 +25,41 @@ class SRAMDevice
 
  public:
 	SRAMDevice();
-	virtual ~SRAMDevice() override;
+	~SRAMDevice() override;
 
 	bool Init() override;
-	void ResetHard() override;
+	void ResetHard(bool poweron) override;
 
-	uint64 Read8(uint32 addr) override;
-	uint64 Read16(uint32 addr) override;
-	uint64 Write8(uint32 addr, uint32 data) override;
-	uint64 Write16(uint32 addr, uint32 data) override;
-	uint64 Peek8(uint32 addr) override;
+	busdata Read8(uint32 addr) override;
+	busdata Read16(uint32 addr) override;
+	busdata Write8(uint32 addr, uint32 data) override;
+	busdata Write16(uint32 addr, uint32 data) override;
+	busdata Peek8(uint32 addr) override;
+	bool Poke8(uint32 addr, uint32 data) override;
+
+	void WriteEnable(bool value);
+	bool IsWriteable() const { return writeable; }
+
+	// SRAM の指定の位置の値を副作用なく読み出す
+	uint32 Get8(uint32 offset) const;
+	uint32 Get16(uint32 offset) const;
+	uint32 Get32(uint32 offset) const;
 
-	void write_enable(bool value);
+	// SRAM $ed0008.L RAM 容量を返す (ホストファイル起動用)
+	uint32 GetRAMSize() const { return Get32(0x0008); }
+
+	// SRAM $ed000c.L ROM 起動アドレスを返す (romemu 用)
+	uint32 GetROMAddr() const { return Get32(0x000c); }
+
+	// SRAM の初期値
+	static std::array<uint8, 0x60> InitialData;
 
  private:
+	// RAM 容量欄を設定値に同期させる。
+	void SyncRAMSize();
+
 	// アドレスデコーダ
-	uint64 Decoder(uint32 addr) const;
+	uint32 Decoder(uint32 addr) const;
 
 	// ファイル
 	std::string filename {};
@@ -44,9 +67,8 @@ class SRAMDevice
 	uint8 *mem {};
 
 	bool writeable {};
-
-	// ホストファイル起動用の読み出し値を返す
-	uint32 PeekHostBoot(uint32 offset) const;
 };
 
-extern std::unique_ptr<SRAMDevice> gSRAM;
+static inline SRAMDevice *GetSRAMDevice() {
+	return Object::GetObject<SRAMDevice>(OBJ_SRAM);
+}