--- nono/vm/xpbus.cpp	2026/04/29 17:05:18	1.1.1.1
+++ nono/vm/xpbus.cpp	2026/04/29 17:05:25	1.1.1.2
@@ -8,6 +8,21 @@
 // XP プロセッサの物理バス
 //
 
+// IODevice
+//   +-- MainbusDevice (InitMainbus() と Read/Write に FC 版がある)
+//   |    +-- Mainbus24Device
+//   |    |    +-- LunaMainbus
+//   |    |    |    +-- Luna1Mainbus
+//   |    |    |    +-- Luna88kMainbus
+//   |    |    +-- NewsMainbus
+//   |    |    +-- Virt68kMainbus
+//   |    +-- X68kMainbus
+//   |    +-- X68kIODevice
+//   |
+//   |       +-------------+
+//   +-------| XPbusDevice | (これはただの IODevice)
+//           +-------------+
+
 // 00000H +-------------------+
 //        | 3Port RAM (128KB) |
 // 20000H +-------------------+
@@ -83,7 +98,7 @@ XPbusDevice::SearchDevice(uint32 addr) c
 	return nopio;
 }
 
-uint64
+busdata
 XPbusDevice::Read8(uint32 addr)
 {
 	addr &= 0x000fffff;
@@ -91,7 +106,7 @@ XPbusDevice::Read8(uint32 addr)
 	return d->Read8(addr);
 }
 
-uint64
+busdata
 XPbusDevice::Read16(uint32 addr)
 {
 	addr &= 0x000fffff;
@@ -99,7 +114,7 @@ XPbusDevice::Read16(uint32 addr)
 	return d->Read16(addr);
 }
 
-uint64
+busdata
 XPbusDevice::Read32(uint32 addr)
 {
 	addr &= 0x000fffff;
@@ -107,7 +122,7 @@ XPbusDevice::Read32(uint32 addr)
 	return d->Read32(addr);
 }
 
-uint64
+busdata
 XPbusDevice::Write8(uint32 addr, uint32 data)
 {
 	addr &= 0x000fffff;
@@ -115,7 +130,7 @@ XPbusDevice::Write8(uint32 addr, uint32
 	return d->Write8(addr, data);
 }
 
-uint64
+busdata
 XPbusDevice::Write16(uint32 addr, uint32 data)
 {
 	addr &= 0x000fffff;
@@ -123,7 +138,7 @@ XPbusDevice::Write16(uint32 addr, uint32
 	return d->Write16(addr, data);
 }
 
-uint64
+busdata
 XPbusDevice::Write32(uint32 addr, uint32 data)
 {
 	addr &= 0x000fffff;
@@ -131,7 +146,7 @@ XPbusDevice::Write32(uint32 addr, uint32
 	return d->Write32(addr, data);
 }
 
-uint64
+busdata
 XPbusDevice::Peek8(uint32 addr)
 {
 	addr &= 0x000fffff;
@@ -139,11 +154,12 @@ XPbusDevice::Peek8(uint32 addr)
 	return d->Peek8(addr);
 }
 
-// このアドレスを担当する次段の IODevice を返す (IOContainerDevice 用)
-IODevice *
-XPbusDevice::GetDevice(uint32 addr) const
+bool
+XPbusDevice::Poke8(uint32 addr, uint32 data)
 {
-	return SearchDevice(addr & 0x000fffff);
+	addr &= 0x000fffff;
+	IODevice *d = SearchDevice(addr);
+	return d->Poke8(addr, data);
 }
 
 // RMCR レジスタを取得する
@@ -179,28 +195,28 @@ XPRAMDevice::~XPRAMDevice()
 {
 }
 
-uint64
+busdata
 XPRAMDevice::Read8(uint32 addr)
 {
 	addr &= 0x1ff;
 	return ram[addr];
 }
 
-uint64
+busdata
 XPRAMDevice::Read16(uint32 addr)
 {
 	putlog(0, "should not be called?");
-	return (uint64)-1;
+	return busdata::BusErr;
 }
 
-uint64
+busdata
 XPRAMDevice::Read32(uint32 addr)
 {
 	putlog(0, "should not be called?");
-	return (uint64)-1;
+	return busdata::BusErr;
 }
 
-uint64
+busdata
 XPRAMDevice::Write8(uint32 addr, uint32 data)
 {
 	addr &= 0x1ff;
@@ -208,33 +224,33 @@ XPRAMDevice::Write8(uint32 addr, uint32
 	return 0;
 }
 
-uint64
+busdata
 XPRAMDevice::Write16(uint32 addr, uint32 data)
 {
 	putlog(0, "should not be called?");
-	return (uint64)-1;
+	return busdata::BusErr;
 }
 
-uint64
+busdata
 XPRAMDevice::Write32(uint32 addr, uint32 data)
 {
 	putlog(0, "should not be called?");
-	return (uint64)-1;
+	return busdata::BusErr;
 }
 
-uint64
+busdata
 XPRAMDevice::Peek8(uint32 addr)
 {
 	addr &= 0x1ff;
 	return ram[addr];
 }
 
-uint64
+bool
 XPRAMDevice::Poke8(uint32 addr, uint32 data)
 {
 	if ((int32)data >= 0) {
 		addr &= 0x1ff;
 		ram[addr] = data;
 	}
-	return 0;
+	return true;
 }