--- nono/vm/gvram.cpp	2026/04/29 17:05:25	1.1.1.8
+++ nono/vm/gvram.cpp	2026/04/29 17:05:43	1.1.1.10
@@ -12,7 +12,6 @@
 // バイトアクセス時は HB() マクロを使用のこと。
 
 #include "gvram.h"
-#include "mpu.h"
 #include "videoctlr.h"
 
 // InsideOut p.135
@@ -22,9 +21,6 @@ static const busdata wait = busdata::Wai
 GVRAMDevice::GVRAMDevice()
 	: inherited(OBJ_GVRAM)
 {
-	uint devlen = 0x20'0000;	// XXX とりあえず
-
-	mem.reset(new uint8[devlen]);
 }
 
 // デストラクタ
@@ -32,44 +28,60 @@ GVRAMDevice::~GVRAMDevice()
 {
 }
 
-busdata
-GVRAMDevice::Read8(uint32 addr)
+// 初期化
+bool
+GVRAMDevice::Init()
 {
-	busdata data;
-	uint32 offset = addr - baseaddr;
-	data = mem[HB(offset)];
-	data |= wait;
-	return data;
+	uint devlen = 0x20'0000;	// XXX とりあえず
+	mem.reset(new(std::nothrow) uint8[devlen]);
+	if ((bool)mem == false) {
+		warnx("Cannot allocate %u bytes at %s", devlen, __method__);
+		return false;
+	}
+
+	return true;
 }
 
-busdata
-GVRAMDevice::Read16(uint32 addr)
+inline uint32
+GVRAMDevice::Decoder(uint32 addr) const
 {
-	busdata data;
-	uint32 offset = addr - baseaddr;
-	data = *(uint16 *)&mem[offset];
-	data |= wait;
-	return data;
+	return addr - baseaddr;
 }
 
 busdata
-GVRAMDevice::Write8(uint32 addr, uint32 data)
+GVRAMDevice::Read(busaddr addr)
 {
-	uint32 offset = addr - baseaddr;
-	mem[HB(offset)] = data;
-	return wait;
+	uint32 offset = Decoder(addr.Addr());
+	busdata data;
+
+	data = *(uint16 *)&mem[offset & ~1U];
+	data |= wait;
+	data |= BusData::Size2;
+	return data;
 }
 
 busdata
-GVRAMDevice::Write16(uint32 addr, uint32 data)
+GVRAMDevice::Write(busaddr addr, uint32 data)
 {
-	uint32 offset = addr - baseaddr;
-	*(uint16 *)&mem[offset] = data;
-	return wait;
+	uint32 offset = Decoder(addr.Addr());
+	uint32 reqsize = addr.GetSize();
+	uint32 datasize = std::min(2 - (offset & 1U), reqsize);
+	data >>= (reqsize - datasize) * 8;
+
+	if (datasize == 1) {
+		mem[HB(offset)] = data;
+	} else {
+		*(uint16 *)&mem[offset] = data;
+	}
+
+	busdata r = wait;
+	r |= busdata::Size(datasize);
+	return r;
 }
 
 busdata
-GVRAMDevice::Peek8(uint32 addr)
+GVRAMDevice::Peek1(uint32 addr)
 {
-	return mem[HB(addr - baseaddr)];
+	uint32 offset = Decoder(addr);
+	return mem[HB(offset)];
 }