--- nono/vm/gvram.cpp	2026/04/29 17:05:18	1.1.1.7
+++ nono/vm/gvram.cpp	2026/04/29 17:05:25	1.1.1.8
@@ -15,6 +15,9 @@
 #include "mpu.h"
 #include "videoctlr.h"
 
+// InsideOut p.135
+static const busdata wait = busdata::Wait(9 * 40_nsec);
+
 // コンストラクタ
 GVRAMDevice::GVRAMDevice()
 	: inherited(OBJ_GVRAM)
@@ -29,41 +32,43 @@ GVRAMDevice::~GVRAMDevice()
 {
 }
 
-uint64
+busdata
 GVRAMDevice::Read8(uint32 addr)
 {
-	mpu->AddCycle(9);	// Inside/Out p.135
+	busdata data;
 	uint32 offset = addr - baseaddr;
-	return mem[HB(offset)];
+	data = mem[HB(offset)];
+	data |= wait;
+	return data;
 }
 
-uint64
+busdata
 GVRAMDevice::Read16(uint32 addr)
 {
-	mpu->AddCycle(9);	// Inside/Out p.135
+	busdata data;
 	uint32 offset = addr - baseaddr;
-	return *(uint16 *)&mem[offset];
+	data = *(uint16 *)&mem[offset];
+	data |= wait;
+	return data;
 }
 
-uint64
+busdata
 GVRAMDevice::Write8(uint32 addr, uint32 data)
 {
-	mpu->AddCycle(9);	// Inside/Out p.135
 	uint32 offset = addr - baseaddr;
 	mem[HB(offset)] = data;
-	return 0;
+	return wait;
 }
 
-uint64
+busdata
 GVRAMDevice::Write16(uint32 addr, uint32 data)
 {
-	mpu->AddCycle(9);	// Inside/Out p.135
 	uint32 offset = addr - baseaddr;
 	*(uint16 *)&mem[offset] = data;
-	return 0;
+	return wait;
 }
 
-uint64
+busdata
 GVRAMDevice::Peek8(uint32 addr)
 {
 	return mem[HB(addr - baseaddr)];