--- nono/vm/busio.h	2026/04/29 17:04:31	1.1
+++ nono/vm/busio.h	2026/04/29 17:04:55	1.1.1.4
@@ -1,18 +1,21 @@
 //
 // nono
-// Copyright (C) 2020 isaki@NetBSD.org
+// Copyright (C) 2020 nono project
+// Licensed under nono-license.txt
 //
 
 // バスとデバイスとのインタフェース。
 // バスに対し、デバイスがどのように接続されているかを記述する。
 
+#pragma once
+
 #if !defined(SELFTEST)
 #include "device.h"
 #endif
 
 // バイトデバイスをバイト、ワード、ロングワードポートにミラー配置する共通部
 template <class T, int rshift>
-class BusIO_B_Base: public T
+class BusIO_B_Base : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
@@ -20,15 +23,15 @@ class BusIO_B_Base: public T
 	}
 
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		return T::Read(Decoder(addr));
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		return T::Write(Decoder(addr), data);
 	}
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		return T::Peek(Decoder(addr));
 	}
 };
@@ -36,18 +39,18 @@ class BusIO_B_Base: public T
 // バイトデバイスをバイトのまま配置する。
 // NPORT によるミラーを行う以外はこれを使わないのと何も変わらない。
 template <class T>
-class BusIO_B: public BusIO_B_Base<T, 0> { };
+class BusIO_B : public BusIO_B_Base<T, 0> { };
 // バイトデバイスをワードにミラー配置する。
 template <class T>
-class BusIO_BB: public BusIO_B_Base<T, 1> { };
+class BusIO_BB : public BusIO_B_Base<T, 1> { };
 // バイトデバイスをロングワードにミラー配置する。
 template <class T>
-class BusIO_BBBB: public BusIO_B_Base<T, 2> { };
+class BusIO_BBBB : public BusIO_B_Base<T, 2> { };
 
 // ワードデバイスをワードのまま配置する。
 // NPORT によるミラーを行う以外はこれを使わないのと何も変わらない。
 template <class T>
-class BusIO_W: public T
+class BusIO_W : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
@@ -55,27 +58,32 @@ class BusIO_W: public T
 	}
 
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return T::Read(Decoder(addr)) >> 8;
 		} else {
 			return T::Read(Decoder(addr)) & 0xff;
 		}
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		return T::Read(Decoder(addr));
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
-		PANIC("not implemented\n");
-		return (int64)-1;	// XXX 未確認
+	uint64 Write8(uint32 addr, uint32 data) override {
+		uint32 offset = Decoder(addr);
+		uint32 old = T::Read(offset);
+		if ((addr & 1) == 0) {
+			return T::Write(offset, ((data << 8) & 0xff00) | (old & 0x00ff));
+		} else {
+			return T::Write(offset, (old & 0xff00) | (data & 0x00ff));
+		}
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		return T::Write(Decoder(addr), data);
 	}
 
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return T::Peek(Decoder(addr)) >> 8;
 		} else {
@@ -85,12 +93,12 @@ class BusIO_W: public T
 };
 
 /* XXX: stub
-class BusIO_L: public T
+class BusIO_L : public T
 */
 
 // バイトデバイスを偶数アドレスに配置し、奇数アドレスはバスエラー。
 template <class T>
-class BusIO_BE: public T
+class BusIO_BE : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
@@ -98,29 +106,29 @@ class BusIO_BE: public T
 	}
 
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return T::Read(Decoder(addr));
 		} else {
 			return (int64)-1;
 		}
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		return (T::Read(Decoder(addr)) << 8) | 0xff;
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		if ((addr & 1) == 0) {
 			return T::Write(Decoder(addr), data);
 		} else {
 			return (int64)-1;
 		}
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		return T::Write(Decoder(addr), data >> 8);
 	}
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return T::Peek(Decoder(addr));
 		} else {
@@ -131,7 +139,7 @@ class BusIO_BE: public T
 
 // バイトデバイスを奇数アドレスに配置し、偶数アドレスはバスエラー。
 template <class T>
-class BusIO_EB: public T
+class BusIO_EB : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
@@ -139,29 +147,29 @@ class BusIO_EB: public T
 	}
 
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return (int64)-1;
 		} else {
 			return T::Read(Decoder(addr));
 		}
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		return T::Read(Decoder(addr)) | 0xff00;
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		if ((addr & 1) == 0) {
 			return (int64)-1;
 		} else {
 			return T::Write(Decoder(addr), data);
 		}
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		return T::Write(Decoder(addr), data & 0xff);
 	}
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return (int64)-1;
 		} else {
@@ -170,9 +178,50 @@ class BusIO_EB: public T
 	}
 };
 
+// バイトデバイスを奇数アドレスに配置し、偶数アドレスは非接続。
+template <class T>
+class BusIO_FB : public T
+{
+ private:
+	inline uint32 Decoder(uint32 addr) {
+		return (addr >> 1) & (T::NPORT - 1);
+	}
+
+ public:
+	uint64 Read8(uint32 addr) override {
+		if ((addr & 1) == 0) {
+			return 0xff;
+		} else {
+			return T::Read(Decoder(addr));
+		}
+	}
+	uint64 Read16(uint32 addr) override {
+		return T::Read(Decoder(addr)) | 0xff00;
+	}
+
+	uint64 Write8(uint32 addr, uint32 data) override {
+		if ((addr & 1) == 0) {
+			return 0;
+		} else {
+			return T::Write(Decoder(addr), data);
+		}
+	}
+	uint64 Write16(uint32 addr, uint32 data) override {
+		return T::Write(Decoder(addr), data & 0xff);
+	}
+
+	uint64 Peek8(uint32 addr) override {
+		if ((addr & 1) == 0) {
+			return 0xff;
+		} else {
+			return T::Peek(Decoder(addr));
+		}
+	}
+};
+
 // バイトデバイスをロングワードの先頭に配置し、他は非接続。
 template <class T>
-class BusIO_BFFF: public T
+class BusIO_BFFF : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
@@ -180,43 +229,43 @@ class BusIO_BFFF: public T
 	}
 
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		if ((addr & 3) == 0) {
 			return T::Read(Decoder(addr));
 		} else {
 			return 0xff;
 		}
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		if ((addr & 2) == 0) {
 			return (T::Read(Decoder(addr)) << 8) | 0xff;
 		} else {
 			return 0xffff;
 		}
 	}
-	virtual uint64 Read32(uint32 addr) {
+	uint64 Read32(uint32 addr) override {
 		return (T::Read(Decoder(addr)) << 24) | 0x00ffffff;
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		if ((addr & 3) == 0) {
 			return T::Write(Decoder(addr), data);
 		} else {
 			return 0;
 		}
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		if ((addr & 2) == 0) {
 			return T::Write(Decoder(addr), data >> 8);
 		} else {
 			return 0;
 		}
 	}
-	virtual uint64 Write32(uint32 addr, uint32 data) {
+	uint64 Write32(uint32 addr, uint32 data) override {
 		return T::Write(Decoder(addr), data >> 24);
 	}
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		if ((addr & 3) == 0) {
 			return T::Peek(Decoder(addr));
 		} else {
@@ -227,33 +276,33 @@ class BusIO_BFFF: public T
 
 // ワードデバイスをロングワードにミラー配置する。
 template <class T>
-class BusIO_WW: public T
+class BusIO_WW : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
 		return (addr >> 2) & (T::NPORT - 1);
 	}
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return T::Read(Decoder(addr)) >> 8;
 		} else {
 			return T::Read(Decoder(addr)) & 0xff;
 		}
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		return T::Read(Decoder(addr));
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		PANIC("not implemented\n");
 		return (int64)-1;	// XXX 未確認
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		return T::Write(Decoder(addr), data);
 	}
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return T::Peek(Decoder(addr)) >> 8;
 		} else {
@@ -264,14 +313,14 @@ class BusIO_WW: public T
 
 // ワードデバイスをロングワード先頭に配置し、他は非接続。
 template <class T>
-class BusIO_WF: public T
+class BusIO_WF : public T
 {
  private:
 	inline uint32 Decoder(uint32 addr) {
 		return (addr >> 2) & (T::NPORT - 1);
 	}
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		switch (addr & 3) {
 		 case 0:
 			return T::Read(Decoder(addr)) >> 8;
@@ -283,7 +332,7 @@ class BusIO_WF: public T
 		}
 		__unreachable();
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		if ((addr & 2) == 0) {
 			return T::Read(Decoder(addr));
 		} else {
@@ -291,18 +340,18 @@ class BusIO_WF: public T
 		}
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		PANIC("not implemented\n");
 		return 0;	// XXX 未確認
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		if ((addr & 2) == 0) {
 			return T::Write(Decoder(addr), data);
 		} else {
 			return 0;
 		}
 	}
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		switch (addr & 3) {
 		 case 0:
 			return T::Peek(Decoder(addr)) >> 8;
@@ -331,7 +380,7 @@ class BusIO_X68kSPC : public T
 	}
 
  public:
-	virtual uint64 Read8(uint32 addr) {
+	uint64 Read8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return (uint64)-1;
 		} else {
@@ -345,7 +394,7 @@ class BusIO_X68kSPC : public T
 			}
 		}
 	}
-	virtual uint64 Read16(uint32 addr) {
+	uint64 Read16(uint32 addr) override {
 		addr = Decoder(addr);
 		if (addr < 0x10) {
 			// 前半16ポートは SASI 跡地
@@ -355,7 +404,7 @@ class BusIO_X68kSPC : public T
 		}
 	}
 
-	virtual uint64 Write8(uint32 addr, uint32 data) {
+	uint64 Write8(uint32 addr, uint32 data) override {
 		if ((addr & 1) == 0) {
 			return (uint64)-1;
 		} else {
@@ -370,7 +419,7 @@ class BusIO_X68kSPC : public T
 			}
 		}
 	}
-	virtual uint64 Write16(uint32 addr, uint32 data) {
+	uint64 Write16(uint32 addr, uint32 data) override {
 		addr = Decoder(addr);
 		if (addr < 0x10) {
 			// 前半16ポートは SASI 跡地。
@@ -382,7 +431,7 @@ class BusIO_X68kSPC : public T
 		}
 	}
 
-	virtual uint64 Peek8(uint32 addr) {
+	uint64 Peek8(uint32 addr) override {
 		if ((addr & 1) == 0) {
 			return (uint64)-1;
 		} else {