diff --git a/21_midi2/main.go b/21_midi2/main.go
new file mode 100644
index 0000000..3a2cccf
--- /dev/null
+++ b/21_midi2/main.go
@@ -0,0 +1,895 @@
+package main
+
+import (
+	"image/color"
+	"machine"
+	"machine/usb/adc/midi"
+	"time"
+
+	pio "github.com/tinygo-org/pio/rp2-pio"
+	"github.com/tinygo-org/pio/rp2-pio/piolib"
+	"tinygo.org/x/drivers"
+	"tinygo.org/x/drivers/encoders"
+	"tinygo.org/x/drivers/ssd1306"
+	"tinygo.org/x/tinydraw"
+	"tinygo.org/x/tinyfont"
+	"tinygo.org/x/tinyfont/shnm"
+)
+
+const (
+	cable    = 0
+	channel  = 1  // ピアノチャンネル
+	drumCh   = 10 // ドラムチャンネル
+	velocity = 0x7F
+	bpm      = 100 // リズムパターンのテンポ
+
+	BassDrum      = 36 // バスドラム
+	SideStick     = 37 // サイドスティック/リムショット
+	SnareDrum     = 38 // スネアドラム
+	HandClap      = 39 // ハンドクラップ
+	ElectricSnare = 40 // エレクトリックスネア
+	LowFloorTom   = 41 // ローフロアタム
+	ClosedHiHat   = 42 // クローズドハイハット
+	HighFloorTom  = 43 // ハイフロアタム
+	PedalHiHat    = 44 // ペダルハイハット
+	LowTom        = 45 // ロータム
+	OpenHiHat     = 46 // オープンハイハット
+	LowMidTom     = 47 // ロー・ミッド・タム
+	HighMidTom    = 48 // ハイミッドタム
+	CrashCymbal1  = 49 // クラッシュシンバル1
+	HighTom       = 50 // ハイトム
+	RideCymbal1   = 51 // ライドシンバル1
+	ChineseCymbal = 52 // チャイニーズシンバル
+	RideBell      = 53 // ライドベル
+	Tambourine    = 54 // タンバリン
+	SplashCymbal  = 55 // スプラッシュシンバル
+	Cowbell       = 56 // カウベル
+	CrashCymbal2  = 57 // クラッシュシンバル2
+	Vibraslap     = 58 // ビブラスラップ
+	RideCymbal2   = 59 // ライドシンバル2
+	Maracas       = 70 // マラカス
+	Claves        = 75 // クラベス
+
+	// LED (GRB)
+	white  = 0x3F3F3FFF // 白色
+	red    = 0x00FF00FF // 赤色
+	green  = 0xFF0000FF // 緑色
+	blue   = 0x0000FFFF // 青色
+	yellow = 0xFFFF00FF // 黄色
+	purple = 0x008080FF // 紫色
+	pink   = 0x69FFB4FF // ピンク色
+	cyan   = 0xFF00FFFF // シアン
+	orange = 0x80FF00FF // オレンジ
+	black  = 0x000000FF // 黒色
+)
+
+// ディスプレイ用の色定義
+var (
+	displayWhite = color.RGBA{R: 0xFF, G: 0xFF, B: 0xFF, A: 0xFF}
+	displayBlack = color.RGBA{R: 0x00, G: 0x00, B: 0x00, A: 0xFF}
+	display      ssd1306.Device
+)
+
+// Not番号から音名のマッピング
+var noteNamesKatakana = map[midi.Note]string{
+	midi.C3: "ド3", midi.C4: "ド4", midi.C5: "ド5", midi.C6: "ド6",
+	midi.D3: "レ3", midi.D4: "レ4", midi.D5: "レ5", midi.D6: "レ6",
+	midi.E3: "ミ3", midi.E4: "ミ4", midi.E5: "ミ5", midi.E6: "ミ6",
+	midi.F3: "ファ3", midi.F4: "ファ4", midi.F5: "ファ5", midi.F6: "ファ6",
+	midi.G3: "ソ3", midi.G4: "ソ4", midi.G5: "ソ5", midi.G6: "ソ6",
+	midi.A3: "ラ3", midi.A4: "ラ4", midi.A5: "ラ5", midi.A6: "ラ6",
+	midi.B3: "シ3", midi.B4: "シ4", midi.B5: "シ5", midi.B6: "シ6",
+}
+
+// ドラム音のマッピング
+var drumNames = map[uint8]string{
+	BassDrum:      "バスドラム",
+	SideStick:     "リムショット",
+	SnareDrum:     "スネア",
+	HandClap:      "クラップ",
+	ElectricSnare: "Eスネア",
+	LowFloorTom:   "ロータム",
+	ClosedHiHat:   "ハイハット(閉)",
+	HighFloorTom:  "ハイタム",
+	PedalHiHat:    "ペダルHH",
+	LowTom:        "ロータム",
+	OpenHiHat:     "ハイハット(開)",
+	CrashCymbal1:  "クラッシュ",
+	RideCymbal1:   "ライド",
+	Cowbell:       "カウベル",
+	Claves:        "クラベス",
+	Maracas:       "マラカス",
+}
+
+var lastNoteOnTime time.Time
+var notesToTurnOff []uint8
+var lastRedrawTime time.Time
+
+type DrumPattern struct {
+	Name    string    // パターン名
+	Steps   [][]uint8 // 各ステップで鳴るドラム音のリスト
+	StepLen int       // 1ステップの長さ (ミリ秒)
+}
+
+var metronomeBeat = DrumPattern{
+	Name: "Metronome",
+	Steps: [][]uint8{
+		{SnareDrum}, // 1拍目: スネア
+		{},          // 2
+		{Claves},    // 3
+		{},          // 4
+		{Claves},    // 5
+		{},          // 6
+		{Claves},    // 7
+		{},          // 8
+		{Claves},    // 9
+		{},          // 10
+		{Claves},    // 11
+		{},          // 12
+		{Claves},    // 13
+		{},          // 14
+		{Claves},    // 15
+		{},          // 16
+	},
+	StepLen: 60000 / bpm / 4, // 16分音符の長さ
+}
+
+var basicBeat = DrumPattern{
+	Name: "8Beat",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat},  // 1拍目
+		{ClosedHiHat},            // 2
+		{SnareDrum, ClosedHiHat}, // 3
+		{OpenHiHat},              // 4
+		{BassDrum, ClosedHiHat},  // 5
+		{ClosedHiHat},            // 6
+		{SnareDrum, ClosedHiHat}, // 7
+		{ClosedHiHat},            // 8
+		{BassDrum, ClosedHiHat},  // 9
+		{ClosedHiHat},            // 10
+		{SnareDrum, ClosedHiHat}, // 11
+		{ClosedHiHat},            // 12
+		{BassDrum, ClosedHiHat},  // 13
+		{ClosedHiHat},            // 14
+		{SnareDrum, ClosedHiHat}, // 15
+		{CrashCymbal1},           // 16
+	},
+	StepLen: 60000 / 100 / 4,
+}
+
+var latinBeatBrazil = DrumPattern{
+	Name: "LatinBrazil",
+	Steps: [][]uint8{
+		{BassDrum, Maracas},  // 1
+		{Claves},             // 2
+		{SideStick, Maracas}, // 3
+		{Cowbell},            // 4
+
+		{BassDrum, Maracas},  // 5
+		{Claves},             // 6
+		{SideStick, Maracas}, // 7
+		{Cowbell},            // 8
+
+		{BassDrum, Maracas},  // 9
+		{Claves},             // 10
+		{SideStick, Maracas}, // 11
+		{Cowbell},            // 12
+
+		{SideStick, Maracas}, // 13
+		{Claves},             // 14
+		{Maracas, Cowbell},   // 15
+		{BassDrum, Claves},   // 16
+	},
+	StepLen: 60000 / 115 / 4,
+}
+
+var drumBassBeat1 = DrumPattern{
+	Name: "DnB 1",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat},  // 1
+		{ClosedHiHat},            // 2
+		{ClosedHiHat},            // 3
+		{BassDrum},               // 4
+		{SnareDrum, ClosedHiHat}, // 5
+		{ClosedHiHat},            // 6
+		{ClosedHiHat},            // 7
+		{BassDrum},               // 8
+		{ClosedHiHat},            // 9
+		{ClosedHiHat},            // 10
+		{ClosedHiHat},            // 11
+		{BassDrum},               // 12
+		{SnareDrum, ClosedHiHat}, // 13
+		{ClosedHiHat},            // 14
+		{ClosedHiHat},            // 15
+		{ClosedHiHat},            // 16
+	},
+	StepLen: 60000 / 174 / 4,
+}
+
+var drumBassBeat2 = DrumPattern{
+	Name: "DnB 2",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat}, // 1
+		{ClosedHiHat},           // 2
+		{ClosedHiHat},           // 3
+		{BassDrum},              // 4
+
+		{SnareDrum, ClosedHiHat}, // 5
+		{ClosedHiHat},            // 6
+		{ClosedHiHat, BassDrum},  // 7
+		{ClosedHiHat},            // 8
+
+		{BassDrum, ClosedHiHat}, // 9
+		{ClosedHiHat},           // 10
+		{SnareDrum},             // 11
+		{OpenHiHat},             // 12
+
+		{SnareDrum, ClosedHiHat}, // 13
+		{ClosedHiHat},            // 14
+		{SideStick, BassDrum},    // 15
+		{ClosedHiHat},            // 16
+	},
+	StepLen: 60000 / 176 / 4,
+}
+
+var drumBassJungle = DrumPattern{
+	Name: "DnB Jungle",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat, CrashCymbal1},
+		{ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+
+		{SnareDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+
+		{BassDrum, ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{OpenHiHat, SideStick},
+
+		{SnareDrum, ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{ClosedHiHat},
+	},
+	StepLen: 60000 / 185 / 4,
+}
+
+var drumBassRollin = DrumPattern{
+	Name: "DnB Rollin",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{BassDrum},
+		{ClosedHiHat},
+		{SnareDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{SnareDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{BassDrum, OpenHiHat},
+		{ClosedHiHat},
+		{SideStick, ClosedHiHat},
+		{ClosedHiHat},
+	},
+	StepLen: 60000 / 180 / 4,
+}
+
+var drumBassStepJump = DrumPattern{
+	Name: "DnB StepJump",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat, CrashCymbal1},
+		{},
+		{ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{},
+		{SnareDrum, OpenHiHat},
+		{BassDrum},
+		{ClosedHiHat},
+		{BassDrum},
+		{},
+		{ClosedHiHat},
+		{SnareDrum, ClosedHiHat},
+		{BassDrum},
+		{ClosedHiHat},
+		{SideStick},
+		{OpenHiHat},
+	},
+	StepLen: 60000 / 174 / 4,
+}
+
+var drumBassTechstep = DrumPattern{
+	Name: "DnB TechStep",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat},
+		{},
+		{ClosedHiHat},
+		{BassDrum, ClosedHiHat},
+		{SnareDrum},
+		{},
+		{BassDrum, ClosedHiHat},
+		{ClosedHiHat},
+		{BassDrum},
+		{ClosedHiHat},
+		{SnareDrum},
+		{ClosedHiHat},
+		{ClosedHiHat},
+		{},
+		{BassDrum, SideStick},
+		{ClosedHiHat},
+	},
+	StepLen: 60000 / 176 / 4,
+}
+
+var drumBassNeuro = DrumPattern{
+	Name: "DnB Neuro",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat, CrashCymbal1}, // 1
+		{},                                    // 2
+		{ClosedHiHat},                         // 3
+		{SnareDrum, ClosedHiHat},              // 4
+		{ClosedHiHat},                         // 5
+		{BassDrum, ClosedHiHat},               // 6
+		{ClosedHiHat},                         // 7
+		{ClosedHiHat},                         // 8
+		{BassDrum, ClosedHiHat},               // 9
+		{},                                    // 10
+		{ClosedHiHat, SnareDrum},              // 11
+		{OpenHiHat},                           // 12
+		{BassDrum, ClosedHiHat},               // 13
+		{ClosedHiHat},                         // 14
+		{SideStick, ClosedHiHat},              // 15
+		{ClosedHiHat},                         // 16
+	},
+	StepLen: 60000 / 178 / 4,
+}
+
+var drumBassLiquid = DrumPattern{
+	Name: "DnB Liquid",
+	Steps: [][]uint8{
+		{BassDrum, ClosedHiHat},  // 1
+		{ClosedHiHat},            // 2
+		{ClosedHiHat},            // 3
+		{SnareDrum, ClosedHiHat}, // 4
+		{ClosedHiHat},            // 5
+		{BassDrum, ClosedHiHat},  // 6
+		{ClosedHiHat},            // 7
+		{ClosedHiHat},            // 8
+		{BassDrum, ClosedHiHat},  // 9
+		{ClosedHiHat},            // 10
+		{SnareDrum, ClosedHiHat}, // 11
+		{ClosedHiHat},            // 12
+		{ClosedHiHat},            // 13
+		{ClosedHiHat},            // 14
+		{ClosedHiHat},            // 15
+		{ClosedHiHat},            // 16
+	},
+	StepLen: 60000 / 172 / 4,
+}
+
+var drumPatterns = []DrumPattern{
+	metronomeBeat,
+	basicBeat,
+	latinBeatBrazil,
+	drumBassBeat1,
+	drumBassBeat2,
+	drumBassJungle,
+	drumBassRollin,
+	drumBassStepJump,
+	drumBassTechstep,
+	drumBassNeuro,
+	drumBassLiquid,
+}
+
+type State struct {
+	Up               bool
+	Down             bool
+	Left             bool
+	Right            bool
+	Center           bool
+	RotaryButton     bool
+	RotaryLeft       bool
+	RotaryRight      bool
+	Keys             [12]bool
+	ActiveNotes      [12]string // 押されているキーに対応する音名
+	DrumPlaying      bool       // ドラムが再生中かどうか
+	DrumPatternIndex int        // 現在のドラムパターン
+}
+
+// WS2812B LED
+type WS2812B struct {
+	Pin machine.Pin
+	ws  *piolib.WS2812B
+}
+
+func NewWS2812B(pin machine.Pin) *WS2812B {
+	s, _ := pio.PIO0.ClaimStateMachine()
+	ws, _ := piolib.NewWS2812B(s, pin)
+	ws.EnableDMA(true)
+	return &WS2812B{
+		ws: ws,
+	}
+}
+
+func (ws *WS2812B) WriteRaw(rawGRB []uint32) error {
+	return ws.ws.WriteRaw(rawGRB)
+}
+
+func main() {
+	machine.I2C0.Configure(machine.I2CConfig{
+		Frequency: 2.8 * machine.MHz,
+		SDA:       machine.GPIO12,
+		SCL:       machine.GPIO13,
+	})
+
+	// ディスプレイ初期化
+	display = ssd1306.NewI2C(machine.I2C0)
+	display.Configure(ssd1306.Config{
+		Address: 0x3C,
+		Width:   128,
+		Height:  64,
+	})
+	display.SetRotation(drivers.Rotation180)
+	display.ClearDisplay()
+	time.Sleep(50 * time.Millisecond)
+
+	m := midi.Port()
+
+	colPins := []machine.Pin{
+		machine.GPIO5,
+		machine.GPIO6,
+		machine.GPIO7,
+		machine.GPIO8,
+	}
+
+	rowPins := []machine.Pin{
+		machine.GPIO9,
+		machine.GPIO10,
+		machine.GPIO11,
+	}
+
+	for _, c := range colPins {
+		c.Configure(machine.PinConfig{Mode: machine.PinOutput})
+		c.Low()
+	}
+
+	for _, c := range rowPins {
+		c.Configure(machine.PinConfig{Mode: machine.PinInputPulldown})
+	}
+
+	// ピアノ
+	notes := []midi.Note{
+		midi.D5,
+		midi.G4,
+		midi.C4,
+
+		midi.E5,
+		midi.A4,
+		midi.D4,
+
+		midi.F5,
+		midi.B4,
+		midi.E4,
+
+		midi.G5,
+		midi.C5,
+		midi.F4,
+	}
+
+	// Note Colors
+	noteColors := map[midi.Note]uint32{
+		midi.C4: white,
+		midi.C5: white,
+		midi.D4: red,
+		midi.D5: red,
+		midi.E4: green,
+		midi.E5: green,
+		midi.F4: blue,
+		midi.F5: blue,
+		midi.G4: yellow,
+		midi.G5: yellow,
+		midi.A4: purple,
+		midi.B4: pink,
+	}
+
+	state := State{
+		DrumPlaying:      false,
+		DrumPatternIndex: 0, // 最初のドラムパターンを選択
+	}
+
+	// LED
+	colors := make([]uint32, 12)
+	for i := range colors {
+		colors[i] = black
+	}
+
+	ws := NewWS2812B(machine.GPIO1)
+
+	// ロータリーエンコーダーボタン
+	rotaryButton := machine.GPIO2
+	rotaryButton.Configure(machine.PinConfig{Mode: machine.PinInputPullup})
+	prevRotaryButton := rotaryButton.Get()
+
+	// ジョイスティック
+	machine.InitADC()
+
+	ax := machine.ADC{Pin: machine.GPIO29}
+	ax.Configure(machine.ADCConfig{})
+	ay := machine.ADC{Pin: machine.GPIO28}
+	ay.Configure(machine.ADCConfig{})
+
+	// ロータリーエンコーダー
+	rotaryEncoder := encoders.NewQuadratureViaInterrupt(
+		machine.GPIO3,
+		machine.GPIO4,
+	)
+	rotaryEncoder.Configure(encoders.QuadratureConfig{
+		Precision: 4,
+	})
+	encOldValue := 0
+
+	// 初期化待ち
+	time.Sleep(1 * time.Second)
+
+	// 初期音色
+	pcOfs := 0x00 // Piano
+	m.Write(programChange(cable, channel, uint8(pcOfs)))
+
+	prevX := uint16(0)
+	prevY := uint16(0)
+
+	// 初期表示
+	redraw(state)
+
+	var lastDrumTime time.Time
+	currentStep := 0
+
+	ticker := time.Tick(1 * time.Millisecond)
+	for {
+		// ジョイスティック X 軸処理
+		{
+			x := ax.Get()
+			if 0x7000 <= x && x <= 0x9000 {
+				x = 0x8000
+			}
+			if prevX != x {
+				m.PitchBend(cable, channel, x>>2)
+				prevX = x
+			}
+		}
+
+		// ジョイスティック Y 軸処理
+		{
+			y := ay.Get()
+			if 0x7000 <= y && y <= 0x9000 {
+				y = 0x8000
+			}
+			if y >= 0x8000 {
+				if prevY != y {
+					m.ControlChange(cable, channel, midi.CCModulationWheel, byte((y-0x8000)>>8))
+					prevY = y
+				}
+			}
+		}
+
+		// ロータリーエンコーダー位置変更時の処理
+		if newValue := rotaryEncoder.Position(); newValue != encOldValue {
+			// エンコーダーの変化方向を検出
+			if newValue > encOldValue {
+				// 右回転 - ドラムパターンを次へ
+				state.DrumPatternIndex = (state.DrumPatternIndex + 1) % len(drumPatterns)
+			} else {
+				// 左回転 - ドラムパターンを前へ
+				state.DrumPatternIndex = (state.DrumPatternIndex - 1 + len(drumPatterns)) % len(drumPatterns)
+			}
+
+			// ディスプレイ更新
+			redraw(state)
+
+			encOldValue = newValue
+		}
+
+		// ロータリーエンコーダーボタン処理
+		currentRotaryButton := rotaryButton.Get()
+		if prevRotaryButton && !currentRotaryButton {
+			// ボタンが押された
+			state.DrumPlaying = !state.DrumPlaying
+			// ディスプレイ更新
+			redraw(state)
+		}
+		prevRotaryButton = currentRotaryButton
+
+		<-ticker
+		// ドラムパターン再生処理
+		if state.DrumPlaying && state.DrumPatternIndex >= 0 && state.DrumPatternIndex < len(drumPatterns) {
+			currentPattern := drumPatterns[state.DrumPatternIndex]
+
+			// ノートオフ処理（前回の音を止める）
+			if !lastNoteOnTime.IsZero() && time.Since(lastNoteOnTime) >= 40*time.Millisecond && len(notesToTurnOff) > 0 {
+				for _, note := range notesToTurnOff {
+					m.NoteOff(cable, drumCh, midi.Note(note), 0)
+				}
+				notesToTurnOff = nil // クリア
+			}
+
+			// 次のステップを再生する時間になったか確認
+			if lastDrumTime.IsZero() || time.Since(lastDrumTime) >= time.Duration(currentPattern.StepLen)*time.Millisecond {
+				// 新しい音を鳴らす
+				notesToTurnOff = currentPattern.Steps[currentStep] // オフにする必要のあるノートを保存
+				for _, note := range notesToTurnOff {
+					m.NoteOn(cable, drumCh, midi.Note(note), velocity)
+				}
+				lastNoteOnTime = time.Now() // ノートオン時刻を記録
+
+				// 次のステップに進む
+				currentStep = (currentStep + 1) % len(currentPattern.Steps)
+				lastDrumTime = time.Now()
+			}
+		}
+
+		// キーの状態更新と処理
+		for i, s := range getKeys(colPins, rowPins) {
+			note := notes[i]
+			switch s {
+			case off2on:
+				m.NoteOn(cable, channel, note, velocity)
+
+				// 対応する色をLEDに設定
+				if color, exists := noteColors[note]; exists {
+					colors[i] = color
+				} else {
+					colors[i] = white // マッピングがない場合は白色を使用
+				}
+
+				// カタカナ音名を保存
+				if name, exists := noteNamesKatakana[note]; exists {
+					state.ActiveNotes[i] = name
+				} else {
+					state.ActiveNotes[i] = ""
+				}
+
+				state.Keys[i] = true
+
+			case on2off:
+				m.NoteOff(cable, channel, note, velocity)
+
+				// LED の色をリセット
+				colors[i] = black
+
+				// 音名をクリア
+				state.ActiveNotes[i] = ""
+				state.Keys[i] = false
+			}
+		}
+
+		// redraw は毎フレームではなく、一定間隔にする（例: 100ms）
+		now := time.Now()
+		if true {
+			if lastRedrawTime.IsZero() || now.Sub(lastRedrawTime) >= 100*time.Millisecond {
+				// LED に色を反映
+				ws.WriteRaw(colors)
+
+				// 画面を更新
+				redraw(state)
+				lastRedrawTime = now
+			}
+		}
+	}
+}
+
+func redraw(state State) {
+	display.ClearBuffer()
+
+	sz := int16(8)
+
+	// ドラムパターン情報を表示
+	patternName := "なし"
+	if state.DrumPatternIndex >= 0 && state.DrumPatternIndex < len(drumPatterns) {
+		patternName = drumPatterns[state.DrumPatternIndex].Name
+	}
+	tinyfont.WriteLine(&display, &shnm.Shnmk12, 5, 12, patternName, displayWhite)
+
+	if state.DrumPlaying {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, 5, 24, "State: Playing", displayWhite)
+	} else {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, 5, 24, "State: Pausing", displayWhite)
+	}
+
+	// キーボード表示
+	x := 128/2 - (sz+2)*2
+
+	fontKeyNameX := x + (sz+2)*5 - 4
+	fontKeyNameY := (sz+2)*(3+0) + sz + 8
+
+	// 1行目のキー
+	Rectangle(state.Keys[0], &display, x+(sz+2)*0, (sz+2)*(3+0), sz, sz, displayWhite)
+	Rectangle(state.Keys[3], &display, x+(sz+2)*1, (sz+2)*(3+0), sz, sz, displayWhite)
+	Rectangle(state.Keys[6], &display, x+(sz+2)*2, (sz+2)*(3+0), sz, sz, displayWhite)
+	Rectangle(state.Keys[9], &display, x+(sz+2)*3, (sz+2)*(3+0), sz, sz, displayWhite)
+
+	// 音名表示
+	if state.ActiveNotes[0] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[0], displayWhite)
+	}
+	if state.ActiveNotes[3] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[3], displayWhite)
+	}
+	if state.ActiveNotes[6] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[6], displayWhite)
+	}
+	if state.ActiveNotes[9] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[9], displayWhite)
+	}
+
+	// 2行目のキー
+	Rectangle(state.Keys[1], &display, x+(sz+2)*0, (sz+2)*(3+1), sz, sz, displayWhite)
+	Rectangle(state.Keys[4], &display, x+(sz+2)*1, (sz+2)*(3+1), sz, sz, displayWhite)
+	Rectangle(state.Keys[7], &display, x+(sz+2)*2, (sz+2)*(3+1), sz, sz, displayWhite)
+	Rectangle(state.Keys[10], &display, x+(sz+2)*3, (sz+2)*(3+1), sz, sz, displayWhite)
+
+	// 音名表示
+	if state.ActiveNotes[1] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[1], displayWhite)
+	}
+	if state.ActiveNotes[4] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[4], displayWhite)
+	}
+	if state.ActiveNotes[7] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[7], displayWhite)
+	}
+	if state.ActiveNotes[10] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[10], displayWhite)
+	}
+
+	// 3行目のキー
+	Rectangle(state.Keys[2], &display, x+(sz+2)*0, (sz+2)*(3+2), sz, sz, displayWhite)
+	Rectangle(state.Keys[5], &display, x+(sz+2)*1, (sz+2)*(3+2), sz, sz, displayWhite)
+	Rectangle(state.Keys[8], &display, x+(sz+2)*2, (sz+2)*(3+2), sz, sz, displayWhite)
+	Rectangle(state.Keys[11], &display, x+(sz+2)*3, (sz+2)*(3+2), sz, sz, displayWhite)
+
+	// 音名表示
+	if state.ActiveNotes[2] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[2], displayWhite)
+	}
+	if state.ActiveNotes[5] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[5], displayWhite)
+	}
+	if state.ActiveNotes[8] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[8], displayWhite)
+	}
+	if state.ActiveNotes[11] != "" {
+		tinyfont.WriteLine(&display, &shnm.Shnmk12, fontKeyNameX, fontKeyNameY, state.ActiveNotes[11], displayWhite)
+	}
+
+	display.Display()
+}
+
+func Rectangle(b bool, d drivers.Displayer, x int16, y int16, w int16, h int16, c color.RGBA) error {
+	if b {
+		tinydraw.FilledRectangle(d, x, y, w, h, c)
+	} else {
+		tinydraw.Rectangle(d, x, y, w, h, c)
+	}
+	return nil
+}
+
+var States [12]state
+
+type state int8
+
+const (
+	off state = iota
+	off2on
+	off2on2
+	off2on3
+	off2on4
+	off2onX
+	on
+	on2off
+	on2off2
+	on2off3
+	on2off4
+	on2off5
+)
+
+func getKeys(colPins, rowPins []machine.Pin) []state {
+	colPins[0].Configure(machine.PinConfig{Mode: machine.PinOutput})
+	colPins[0].High()
+
+	States[0] = updateState(States[0], rowPins[0].Get())
+	States[1] = updateState(States[1], rowPins[1].Get())
+	States[2] = updateState(States[2], rowPins[2].Get())
+
+	colPins[0].Low()
+	colPins[0].Configure(machine.PinConfig{Mode: machine.PinInputPulldown})
+
+	colPins[1].Configure(machine.PinConfig{Mode: machine.PinOutput})
+	colPins[1].High()
+
+	States[3] = updateState(States[3], rowPins[0].Get())
+	States[4] = updateState(States[4], rowPins[1].Get())
+	States[5] = updateState(States[5], rowPins[2].Get())
+
+	colPins[1].Low()
+	colPins[1].Configure(machine.PinConfig{Mode: machine.PinInputPulldown})
+
+	colPins[2].Configure(machine.PinConfig{Mode: machine.PinOutput})
+	colPins[2].High()
+
+	States[6] = updateState(States[6], rowPins[0].Get())
+	States[7] = updateState(States[7], rowPins[1].Get())
+	States[8] = updateState(States[8], rowPins[2].Get())
+
+	colPins[2].Low()
+	colPins[2].Configure(machine.PinConfig{Mode: machine.PinInputPulldown})
+
+	colPins[3].Configure(machine.PinConfig{Mode: machine.PinOutput})
+	colPins[3].High()
+
+	States[9] = updateState(States[9], rowPins[0].Get())
+	States[10] = updateState(States[10], rowPins[1].Get())
+	States[11] = updateState(States[11], rowPins[2].Get())
+	colPins[3].Low()
+	colPins[3].Configure(machine.PinConfig{Mode: machine.PinInputPulldown})
+
+	return States[:]
+}
+
+func updateState(s state, btn bool) state {
+	ret := s
+	switch s {
+	case off:
+		if btn {
+			ret = off2on
+		}
+	case off2on:
+		ret = on
+	case on:
+		if !btn {
+			ret = on2off2
+		}
+	case on2off2:
+		if btn {
+			ret = on
+		} else {
+			ret = on2off3
+		}
+	case on2off3:
+		ret = on2off4
+		if btn {
+			ret = on
+		} else {
+			ret = on2off4
+		}
+	case on2off4:
+		if btn {
+			ret = on
+		} else {
+			ret = on2off5
+		}
+	case on2off5:
+		if btn {
+			ret = on
+		} else {
+			ret = on2off
+		}
+	case on2off:
+		ret = off
+	}
+	return ret
+}
+
+func programChange(cable, channel uint8, patch uint8) []byte {
+	var pbuf [4]byte
+	pbuf[0] = ((cable & 0xf) << 4) | midi.CINProgramChange
+	pbuf[1] = midi.MsgProgramChange | ((channel - 1) & 0x0f) // ← 1-origin に対応
+	pbuf[2] = patch & 0x7f
+	pbuf[3] = 0x00
+	return pbuf[:4]
+}