--- nono/vm/subram.h	2026/04/29 17:05:17	1.1.1.1
+++ nono/vm/subram.h	2026/04/29 17:06:00	1.1.1.5
@@ -17,26 +17,35 @@ class SubRAMBaseDevice : public IODevice
 {
 	using inherited = IODevice;
  public:
-	SubRAMBaseDevice(int objid_, uint ramsize_kb);
-	virtual ~SubRAMBaseDevice() override;
+	SubRAMBaseDevice(uint objid_, uint ramsize_kb);
+	~SubRAMBaseDevice() override;
 
+	bool Init() override;
 	void ResetHard(bool poweron) override;
 
-	uint64 Read8(uint32 addr) override;
-	uint64 Read16(uint32 addr) override;
-	uint64 Read32(uint32 addr) override;
-	uint64 Write8(uint32 addr, uint32 data) override;
-	uint64 Write16(uint32 addr, uint32 data) override;
-	uint64 Write32(uint32 addr, uint32 data) override;
-	uint64 Peek8(uint32 addr) override;
-	uint64 Poke8(uint32 addr, uint32 data) override;
+	busdata Read(busaddr addr) override;
+	busdata Write(busaddr addr, uint32 data) override;
+	busdata Peek1(uint32 addr) override;
+	bool Poke1(uint32 addr, uint32 data) override;
+
+	// XP からのバイトアクセス
+	busdata Read1(uint32 addr) override;
+	busdata Write1(uint32 addr, uint32 data) override;
+
+	// Lance からのワードアクセス (これは override ではない)
+	busdata Read2(uint32 addr);
+	busdata Write2(uint32 addr, uint32 data);
+	busdata Peek2(uint32 addr) const;
 
  private:
 	// アドレスデコーダ
-	uint64 Decoder(uint32 addr) const;
+	uint32 Decoder(uint32 addr) const;
+
+	// RAM 容量(バイト単位)を取得
+	uint GetSize() const { return mask + 1; }
 
 	std::unique_ptr<uint8[]> ram {};
-	uint ramsize {};
+	uint32 mask {};
 };
 
 // サブメモリ (XP/Lance との共有 RAM)
@@ -44,21 +53,21 @@ class SubRAMDevice : public SubRAMBaseDe
 {
 	using inherited = SubRAMBaseDevice;
  public:
-	SubRAMDevice(int ramsize_kb);
+	explicit SubRAMDevice(uint ramsize_kb);
 	~SubRAMDevice() override;
 
 	void ResetHard(bool poweron) override;
 };
 
-// サブメモリ2 (XP の非共有部)
+// サブメモリ 2 (XP の非共有部)
 class SubRAM2Device : public SubRAMBaseDevice
 {
 	using inherited = SubRAMBaseDevice;
  public:
-	SubRAM2Device(int ramsize_kb);
+	explicit SubRAM2Device(uint ramsize_kb);
 	~SubRAM2Device() override;
 };
 
-static inline SubRAMDevice *GetSubRAMDevice() {
+inline SubRAMDevice *GetSubRAMDevice() {
 	return Object::GetObject<SubRAMDevice>(OBJ_SUBRAM);
 }