diff --git a/aa-graph.h b/aa-graph.h
new file mode 100644
index 0000000..c375c0e
--- /dev/null
+++ b/aa-graph.h
@@ -0,0 +1,924 @@
+#ifndef GRAPH_H
+#define GRAPH_H
+
+const char graph_html[] PROGMEM = R"rawliteral(
+<!DOCTYPE html>
+<html>
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
+    <title>CAN Signal Graph Setup - Byun Logger</title>
+    <style>
+        * { margin: 0; padding: 0; box-sizing: border-box; }
+        body {
+            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
+            background: linear-gradient(135deg, #43cea2 0%, #185a9d 100%);
+            min-height: 100vh;
+            padding: 10px;
+        }
+        .container {
+            max-width: 1600px;
+            margin: 0 auto;
+            background: white;
+            border-radius: 15px;
+            box-shadow: 0 20px 60px rgba(0,0,0,0.3);
+            overflow: hidden;
+        }
+        .header {
+            background: linear-gradient(135deg, #43cea2 0%, #185a9d 100%);
+            color: white;
+            padding: 20px;
+            text-align: center;
+        }
+        .header h1 { font-size: 1.8em; margin-bottom: 5px; }
+        .header p { opacity: 0.9; font-size: 0.9em; }
+        .nav {
+            background: #2c3e50;
+            padding: 10px;
+            display: flex;
+            gap: 10px;
+            flex-wrap: wrap;
+            justify-content: center;
+        }
+        .nav a {
+            color: white;
+            text-decoration: none;
+            padding: 10px 15px;
+            border-radius: 5px;
+            transition: all 0.3s;
+            font-size: 0.9em;
+        }
+        .nav a:hover { background: #34495e; }
+        .nav a.active { background: #3498db; }
+        .content { padding: 15px; }
+        
+        .dbc-upload {
+            background: #f8f9fa;
+            padding: 20px;
+            border-radius: 10px;
+            margin-bottom: 15px;
+            border: 2px solid #e0e0e0;
+        }
+        .upload-area {
+            border: 3px dashed #43cea2;
+            border-radius: 10px;
+            padding: 30px 20px;
+            text-align: center;
+            cursor: pointer;
+            transition: all 0.3s;
+            background: white;
+        }
+        .upload-area:hover { 
+            background: #f0f9ff; 
+            border-color: #185a9d;
+            transform: translateY(-2px);
+        }
+        .upload-area input { display: none; }
+        .upload-icon {
+            font-size: 3em;
+            margin-bottom: 10px;
+        }
+        
+        .signal-selector {
+            background: #f8f9fa;
+            padding: 15px;
+            border-radius: 10px;
+            margin-bottom: 15px;
+            border: 2px solid #e0e0e0;
+        }
+        
+        .search-container {
+            margin-bottom: 15px;
+            position: relative;
+        }
+        .search-box {
+            width: 100%;
+            padding: 12px 12px 12px 40px;
+            border: 2px solid #43cea2;
+            border-radius: 8px;
+            font-size: 0.95em;
+            transition: all 0.3s;
+        }
+        .search-box:focus {
+            outline: none;
+            border-color: #185a9d;
+            box-shadow: 0 0 0 3px rgba(67, 206, 162, 0.1);
+        }
+        .search-icon {
+            position: absolute;
+            left: 12px;
+            top: 50%;
+            transform: translateY(-50%);
+            color: #43cea2;
+            font-size: 1.2em;
+        }
+        .search-info {
+            margin-top: 8px;
+            padding: 8px 12px;
+            background: #e3f2fd;
+            border-radius: 5px;
+            font-size: 0.85em;
+            color: #185a9d;
+            font-weight: 600;
+        }
+        .no-results {
+            text-align: center;
+            padding: 40px 20px;
+            color: #666;
+            font-size: 0.95em;
+        }
+        .no-results-icon {
+            font-size: 3em;
+            margin-bottom: 10px;
+            opacity: 0.5;
+        }
+        
+        .sort-controls {
+            display: flex;
+            gap: 10px;
+            margin-bottom: 15px;
+            align-items: center;
+            flex-wrap: wrap;
+        }
+        .sort-label {
+            font-weight: 600;
+            color: #333;
+            font-size: 0.9em;
+        }
+        .sort-btn {
+            padding: 8px 15px;
+            border: 2px solid #43cea2;
+            background: white;
+            border-radius: 5px;
+            font-size: 0.85em;
+            cursor: pointer;
+            transition: all 0.3s;
+            font-weight: 600;
+        }
+        .sort-btn:hover {
+            background: #f0f9ff;
+            transform: translateY(-2px);
+        }
+        .sort-btn.active {
+            background: #43cea2;
+            color: white;
+        }
+        .signal-grid {
+            display: grid;
+            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
+            gap: 10px;
+            margin-top: 15px;
+        }
+        .signal-item {
+            background: white;
+            padding: 12px;
+            border-radius: 8px;
+            border: 2px solid #ddd;
+            cursor: pointer;
+            transition: all 0.3s;
+            position: relative;
+        }
+        .signal-item:hover { 
+            border-color: #43cea2; 
+            transform: translateY(-2px);
+            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
+        }
+        .signal-item.selected { 
+            border-color: #185a9d; 
+            background: linear-gradient(135deg, rgba(67, 206, 162, 0.1) 0%, rgba(24, 90, 157, 0.1) 100%);
+        }
+        .signal-item.selected::before {
+            content: '✓';
+            position: absolute;
+            top: 8px;
+            right: 8px;
+            background: #185a9d;
+            color: white;
+            width: 24px;
+            height: 24px;
+            border-radius: 50%;
+            display: flex;
+            align-items: center;
+            justify-content: center;
+            font-weight: 700;
+            font-size: 0.9em;
+        }
+        .signal-name { 
+            font-weight: 600; 
+            color: #333; 
+            margin-bottom: 5px; 
+            font-size: 0.95em;
+            padding-right: 30px;
+        }
+        .signal-info { 
+            font-size: 0.8em; 
+            color: #666; 
+            line-height: 1.5;
+        }
+        .signal-info-row {
+            margin-bottom: 3px;
+        }
+        .highlight {
+            background-color: #ffeb3b;
+            padding: 2px 0;
+            font-weight: 600;
+        }
+        
+        .controls {
+            display: flex;
+            gap: 8px;
+            margin-bottom: 15px;
+            flex-wrap: wrap;
+        }
+        .btn {
+            padding: 10px 20px;
+            border: none;
+            border-radius: 5px;
+            font-size: 0.9em;
+            font-weight: 600;
+            cursor: pointer;
+            transition: all 0.3s;
+        }
+        .btn-primary { background: linear-gradient(135deg, #43cea2 0%, #185a9d 100%); color: white; }
+        .btn-success { background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%); color: white; }
+        .btn-danger { background: linear-gradient(135deg, #eb3349 0%, #f45c43 100%); color: white; }
+        .btn-secondary { background: linear-gradient(135deg, #bdc3c7 0%, #95a5a6 100%); color: white; }
+        .btn:hover { 
+            transform: translateY(-2px); 
+            box-shadow: 0 5px 15px rgba(0,0,0,0.3); 
+        }
+        
+        h2 {
+            color: #333;
+            margin: 20px 0 15px 0;
+            padding-bottom: 8px;
+            border-bottom: 3px solid #43cea2;
+            font-size: 1.3em;
+        }
+        
+        .status { 
+            padding: 12px 15px; 
+            border-radius: 8px; 
+            margin-bottom: 15px; 
+            font-size: 0.9em;
+            border-left: 4px solid;
+        }
+        .status.success { 
+            background: #d4edda; 
+            color: #155724;
+            border-color: #28a745;
+        }
+        .status.error { 
+            background: #f8d7da; 
+            color: #721c24;
+            border-color: #dc3545;
+        }
+        .status.info {
+            background: #d1ecf1;
+            color: #0c5460;
+            border-color: #17a2b8;
+        }
+        
+        .selection-info {
+            background: linear-gradient(135deg, #e3f2fd 0%, #f0f9ff 100%);
+            padding: 15px 20px;
+            border-radius: 8px;
+            margin-bottom: 15px;
+            border-left: 4px solid #185a9d;
+            font-size: 0.95em;
+            color: #333;
+            display: flex;
+            justify-content: space-between;
+            align-items: center;
+            flex-wrap: wrap;
+            gap: 10px;
+        }
+        .selection-info strong {
+            color: #185a9d;
+            font-size: 1.1em;
+        }
+        .selection-count {
+            background: #185a9d;
+            color: white;
+            padding: 8px 16px;
+            border-radius: 20px;
+            font-weight: 700;
+            font-size: 1em;
+        }
+        
+        .info-box {
+            background: linear-gradient(135deg, #e3f2fd 0%, #f0f9ff 100%);
+            padding: 15px 20px;
+            border-radius: 8px;
+            margin-top: 15px;
+            border-left: 4px solid #185a9d;
+        }
+        .info-box p {
+            color: #333;
+            font-size: 0.9em;
+            margin: 0;
+            line-height: 1.6;
+        }
+        .info-box strong {
+            color: #185a9d;
+        }
+        
+        @media (max-width: 768px) {
+            body { padding: 5px; }
+            .header h1 { font-size: 1.5em; }
+            .content { padding: 10px; }
+            .signal-grid { 
+                grid-template-columns: 1fr; 
+                gap: 8px; 
+            }
+            h2 { font-size: 1.1em; }
+            .controls {
+                flex-direction: column;
+            }
+            .btn {
+                width: 100%;
+            }
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <div class="header">
+            <h1>📊 CAN Signal Graph Setup</h1>
+            <p>Configure real-time signal visualization (Max 20 signals)</p>
+        </div>
+        
+        <div class="nav">
+            <a href="/">📊 Monitor</a>
+            <a href="/transmit">📤 Transmit</a>
+            <a href="/graph" class="active">📈 Graph</a>
+            <a href="/graph-view">📊 Graph View</a>
+            <a href="/settings">⚙️ Settings</a>
+            <a href="/serial">📟 Serial</a>
+        </div>
+        
+        <div class="content">
+            <div id="status" class="status" style="display:none;"></div>
+            
+            <h2>📁 Upload DBC File</h2>
+            <div class="dbc-upload">
+                <div class="upload-area" onclick="document.getElementById('dbc-file').click()">
+                    <input type="file" id="dbc-file" accept=".dbc" onchange="loadDBCFile(event)">
+                    <div class="upload-icon">📄</div>
+                    <p style="font-size: 1.1em; margin-bottom: 8px; font-weight: 600;">Click or Drag & Drop DBC File</p>
+                    <p style="color: #666; font-size: 0.85em;" id="dbc-status">No file loaded</p>
+                </div>
+            </div>
+            
+            <div id="signal-section" style="display:none;">
+                <h2>🎯 Select Signals (Max 20)</h2>
+                
+                <div class="selection-info">
+                    <div>
+                        <strong>Selected Signals</strong>
+                    </div>
+                    <div class="selection-count">
+                        <span id="selected-count">0</span> / 20
+                    </div>
+                </div>
+                
+                <div class="controls">
+                    <button class="btn btn-success" onclick="startGraphing()">▶️ Start Graph Viewer</button>
+                    <button class="btn btn-danger" onclick="stopGraphing()">⏹️ Stop Logging</button>
+                    <button class="btn btn-secondary" onclick="clearSelection()">🗑️ Clear Selection</button>
+                    <button class="btn btn-primary" onclick="debugDBCInfo()">🐛 Debug Info</button>
+                </div>
+                
+                <div class="signal-selector">
+                    <div class="search-container">
+                        <span class="search-icon">🔍</span>
+                        <input type="text" 
+                               id="search-box" 
+                               class="search-box" 
+                               placeholder="Search by signal name, CAN ID (hex/dec), message name, or unit..."
+                               oninput="filterSignals()">
+                        <div id="search-info" class="search-info" style="display:none;"></div>
+                    </div>
+                    
+                    <div class="sort-controls">
+                        <span class="sort-label">📊 Sort by:</span>
+                        <button class="sort-btn active" id="sort-selection" onclick="setSortMode('selection')">
+                            ✓ Selection Order
+                        </button>
+                        <button class="sort-btn" id="sort-name-asc" onclick="setSortMode('name-asc')">
+                            🔼 Name (A→Z)
+                        </button>
+                        <button class="sort-btn" id="sort-name-desc" onclick="setSortMode('name-desc')">
+                            🔽 Name (Z→A)
+                        </button>
+                        <button class="sort-btn" id="sort-id-asc" onclick="setSortMode('id-asc')">
+                            🔼 CAN ID
+                        </button>
+                    </div>
+                    <div id="signal-list" class="signal-grid"></div>
+                </div>
+                
+                <div class="info-box">
+                    <p>
+                        <strong>ℹ️ How to use:</strong>
+                    </p>
+                    <p style="margin-top: 8px;">
+                        1. Select signals from the list above (click to toggle)<br>
+                        2. Click <strong>"▶️ Start Graph Viewer"</strong> to open a new window<br>
+                        3. The graph will display real-time data from the selected signals<br>
+                        4. Your selections are automatically saved in browser storage
+                    </p>
+                </div>
+            </div>
+        </div>
+    </div>
+    
+    <script>
+        let ws;
+        let dbcData = { messages: {}, valueTables: {} };
+        let selectedSignals = [];
+        let allSignals = [];
+        let filteredSignals = [];
+        let sortMode = 'selection';
+        let searchQuery = '';
+        const MAX_SIGNALS = 20;
+        
+        function initWebSocket() {
+            ws = new WebSocket('ws://' + window.location.hostname + ':81');
+            
+            ws.onopen = function() {
+                console.log('✓ WebSocket connected');
+            };
+            
+            ws.onclose = function() {
+                console.log('✗ WebSocket disconnected');
+                setTimeout(initWebSocket, 3000);
+            };
+            
+            ws.onmessage = function(event) {
+                try {
+                    const data = JSON.parse(event.data);
+                    // 필요시 처리
+                } catch(e) {
+                    console.error('Parse error:', e);
+                }
+            };
+        }
+        
+        function loadDBCFile(event) {
+            const file = event.target.files[0];
+            if (!file) return;
+            
+            showStatus('Loading DBC file: ' + file.name, 'info');
+            
+            const reader = new FileReader();
+            reader.onload = function(e) {
+                const content = e.target.result;
+                parseDBCContent(content);
+                document.getElementById('dbc-status').textContent = '✓ ' + file.name;
+                
+                saveDBCToLocalStorage(content, file.name);
+            };
+            reader.readAsText(file);
+        }
+        
+        function saveDBCToLocalStorage(content, filename) {
+            try {
+                localStorage.setItem('dbc_content', content);
+                localStorage.setItem('dbc_filename', filename);
+                console.log('✓ DBC saved to localStorage:', filename);
+            } catch(e) {
+                console.error('✗ Failed to save DBC:', e);
+                showStatus('Failed to save DBC to storage', 'error');
+            }
+        }
+        
+        function loadDBCFromLocalStorage() {
+            try {
+                const content = localStorage.getItem('dbc_content');
+                const filename = localStorage.getItem('dbc_filename');
+                
+                if (content && filename) {
+                    parseDBCContent(content);
+                    document.getElementById('dbc-status').textContent = '✓ ' + filename + ' (restored)';
+                    showStatus('DBC file restored: ' + filename, 'success');
+                    console.log('✓ DBC restored:', filename);
+                    return true;
+                }
+            } catch(e) {
+                console.error('✗ Failed to load DBC:', e);
+            }
+            return false;
+        }
+        
+        function parseDBCContent(content) {
+            console.log('=== Parsing DBC File ===');
+            dbcData = { messages: {}, valueTables: {} };
+            allSignals = [];
+            const lines = content.split('\n');
+            let currentMessage = null;
+            
+            // 1단계: VAL_ (Value Table) 파싱
+            for (let line of lines) {
+                line = line.trim();
+                
+                if (line.startsWith('VAL_ ')) {
+                    const match = line.match(/VAL_\s+(\d+)\s+(\w+)\s+(.+);/);
+                    if (match) {
+                        const msgId = parseInt(match[1]);
+                        const sigName = match[2];
+                        const valuesStr = match[3];
+                        
+                        const normalizedMsgId = (msgId & 0x80000000) ? (msgId & 0x1FFFFFFF) : msgId;
+                        const key = normalizedMsgId + '_' + sigName;
+                        dbcData.valueTables[key] = {};
+                        
+                        const valueMatches = valuesStr.matchAll(/(\d+)\s+"([^"]+)"/g);
+                        for (let vm of valueMatches) {
+                            dbcData.valueTables[key][parseInt(vm[1])] = vm[2];
+                        }
+                        
+                        console.log('  Value Table: ' + key, dbcData.valueTables[key]);
+                    }
+                }
+            }
+            
+            // 2단계: BO_ (Message) 및 SG_ (Signal) 파싱
+            for (let line of lines) {
+                line = line.trim();
+                
+                if (line.startsWith('BO_ ')) {
+                    const match = line.match(/BO_\s+(\d+)\s+(\w+)\s*:\s*(\d+)/);
+                    if (match) {
+                        let id = parseInt(match[1]);
+                        const name = match[2];
+                        const dlc = parseInt(match[3]);
+                        
+                        if (id & 0x80000000) {
+                            id = id & 0x1FFFFFFF;
+                        }
+                        
+                        currentMessage = {
+                            id: id,
+                            name: name,
+                            dlc: dlc,
+                            signals: []
+                        };
+                        dbcData.messages[id] = currentMessage;
+                        
+                        console.log('Message: ID=' + id + ' (0x' + id.toString(16).toUpperCase() + ') Name=' + name + ' DLC=' + dlc);
+                    }
+                }
+                else if (line.startsWith('SG_ ') && currentMessage) {
+                    const match = line.match(/SG_\s+(\w+)\s*:\s*(\d+)\|(\d+)@([01])([+-])\s*$([^,]+),([^)]+)$\s*$$([^$$]+)$$\s*"([^"]*)"/);
+                    if (match) {
+                        const signalName = match[1];
+                        const signal = {
+                            name: signalName,
+                            startBit: parseInt(match[2]),
+                            bitLength: parseInt(match[3]),
+                            byteOrder: match[4] === '0' ? 'motorola' : 'intel',
+                            signed: match[5] === '-',
+                            factor: parseFloat(match[6]),
+                            offset: parseFloat(match[7]),
+                            minMax: match[8],
+                            unit: match[9],
+                            messageId: currentMessage.id,
+                            messageName: currentMessage.name,
+                            messageDlc: currentMessage.dlc
+                        };
+                        
+                        const vtKey = currentMessage.id + '_' + signalName;
+                        if (dbcData.valueTables[vtKey]) {
+                            signal.valueTable = dbcData.valueTables[vtKey];
+                            console.log('  Signal (with VT): ' + signalName);
+                        } else {
+                            console.log('  Signal: ' + signalName);
+                        }
+                        
+                        currentMessage.signals.push(signal);
+                        allSignals.push(signal);
+                    }
+                }
+            }
+            
+            console.log('=== Parsing Complete ===');
+            console.log('Total Messages: ' + Object.keys(dbcData.messages).length);
+            console.log('Total Signals: ' + allSignals.length);
+            console.log('Total Value Tables: ' + Object.keys(dbcData.valueTables).length);
+            
+            filteredSignals = [...allSignals];
+            displaySignals();
+            showStatus('DBC loaded: ' + Object.keys(dbcData.messages).length + ' messages, ' + allSignals.length + ' signals', 'success');
+        }
+        
+        function filterSignals() {
+            searchQuery = document.getElementById('search-box').value.toLowerCase().trim();
+            
+            if (searchQuery === '') {
+                filteredSignals = [...allSignals];
+                document.getElementById('search-info').style.display = 'none';
+            } else {
+                filteredSignals = allSignals.filter(signal => {
+                    const nameMatch = signal.name.toLowerCase().includes(searchQuery);
+                    const idDecMatch = signal.messageId.toString().includes(searchQuery);
+                    const idHex = signal.messageId.toString(16).toLowerCase();
+                    const idHexMatch = idHex.includes(searchQuery) || idHex.includes(searchQuery.replace('0x', ''));
+                    const msgNameMatch = signal.messageName.toLowerCase().includes(searchQuery);
+                    const unitMatch = signal.unit && signal.unit.toLowerCase().includes(searchQuery);
+                    
+                    return nameMatch || idDecMatch || idHexMatch || msgNameMatch || unitMatch;
+                });
+                
+                const searchInfo = document.getElementById('search-info');
+                searchInfo.textContent = '🔍 Showing ' + filteredSignals.length + ' of ' + allSignals.length + ' signals';
+                searchInfo.style.display = 'block';
+            }
+            
+            displaySignals();
+        }
+        
+        function highlightText(text, query) {
+            if (!query) return text;
+            
+            const regex = new RegExp('(' + query.replace(/[.*+?^${}()|[$$\$$/g, '\\$&') + ')', 'gi');
+            return text.replace(regex, '<span class="highlight">$1</span>');
+        }
+        
+        function setSortMode(mode) {
+            sortMode = mode;
+            
+            document.querySelectorAll('.sort-btn').forEach(btn => btn.classList.remove('active'));
+            document.getElementById('sort-' + mode).classList.add('active');
+            
+            displaySignals();
+            console.log('Sort mode:', mode);
+        }
+        
+        function sortSignals(signals) {
+            if (sortMode === 'name-asc') {
+                return signals.sort((a, b) => a.name.localeCompare(b.name));
+            } else if (sortMode === 'name-desc') {
+                return signals.sort((a, b) => b.name.localeCompare(a.name));
+            } else if (sortMode === 'id-asc') {
+                return signals.sort((a, b) => a.messageId - b.messageId);
+            } else {
+                const selected = signals.filter(s => isSignalSelected(s));
+                const notSelected = signals.filter(s => !isSignalSelected(s));
+                return [...selected, ...notSelected];
+            }
+        }
+        
+        function isSignalSelected(signal) {
+            return selectedSignals.some(s => 
+                s.messageId === signal.messageId && s.name === signal.name);
+        }
+        
+        function displaySignals() {
+            const signalList = document.getElementById('signal-list');
+            signalList.innerHTML = '';
+            
+            const sortedSignals = sortSignals([...filteredSignals]);
+            
+            if (sortedSignals.length === 0) {
+                signalList.innerHTML = 
+                    '<div class="no-results">' +
+                    '<div class="no-results-icon">🔍</div>' +
+                    '<div><strong>No signals found</strong></div>' +
+                    '<div style="margin-top: 8px; color: #999;">Try a different search term</div>' +
+                    '</div>';
+                return;
+            }
+            
+            sortedSignals.forEach(signal => {
+                const item = document.createElement('div');
+                item.className = 'signal-item';
+                
+                if (isSignalSelected(signal)) {
+                    item.classList.add('selected');
+                }
+                
+                item.onclick = () => toggleSignal(signal, item);
+                
+                const canIdHex = '0x' + signal.messageId.toString(16).toUpperCase().padStart(3, '0');
+                const canIdDec = signal.messageId;
+                
+                const highlightedName = highlightText(signal.name, searchQuery);
+                const highlightedId = highlightText(canIdHex, searchQuery);
+                const highlightedMsgName = highlightText(signal.messageName, searchQuery);
+                const unitText = signal.unit ? highlightText(signal.unit, searchQuery) : 'no unit';
+                
+                item.innerHTML = 
+                    '<div class="signal-name">' + highlightedName + '</div>' +
+                    '<div class="signal-info">' +
+                    '<div class="signal-info-row">📍 CAN ID: ' + highlightedId + ' (' + canIdDec + ')</div>' +
+                    '<div class="signal-info-row">📦 Message: ' + highlightedMsgName + '</div>' +
+                    '<div class="signal-info-row">📊 Bit: ' + signal.startBit + '|' + signal.bitLength + ' | Unit: ' + unitText + '</div>' +
+                    '</div>';
+                
+                signalList.appendChild(item);
+            });
+            
+            document.getElementById('signal-section').style.display = 'block';
+            updateSelectionCount();
+        }
+        
+        function updateSelectionCount() {
+            document.getElementById('selected-count').textContent = selectedSignals.length;
+        }
+        
+        function toggleSignal(signal, element) {
+            const index = selectedSignals.findIndex(s => 
+                s.messageId === signal.messageId && s.name === signal.name);
+            
+            if (index >= 0) {
+                selectedSignals.splice(index, 1);
+                element.classList.remove('selected');
+            } else {
+                if (selectedSignals.length >= MAX_SIGNALS) {
+                    showStatus('⚠️ Maximum ' + MAX_SIGNALS + ' signals allowed!', 'error');
+                    return;
+                }
+                selectedSignals.push(signal);
+                element.classList.add('selected');
+            }
+            
+            updateSelectionCount();
+            saveSelectedSignals();
+            
+            if (sortMode === 'selection') {
+                displaySignals();
+            }
+        }
+        
+        function clearSelection() {
+            selectedSignals = [];
+            document.querySelectorAll('.signal-item').forEach(item => {
+                item.classList.remove('selected');
+            });
+            
+            updateSelectionCount();
+            saveSelectedSignals();
+            
+            if (sortMode === 'selection') {
+                displaySignals();
+            }
+            
+            showStatus('Selection cleared', 'info');
+        }
+        
+        function saveSelectedSignals() {
+            try {
+                localStorage.setItem('selected_signals', JSON.stringify(selectedSignals));
+                localStorage.setItem('sort_mode', sortMode);
+                console.log('✓ Saved ' + selectedSignals.length + ' signals');
+            } catch(e) {
+                console.error('✗ Failed to save signals:', e);
+            }
+        }
+        
+        function loadSelectedSignals() {
+            try {
+                const saved = localStorage.getItem('selected_signals');
+                const savedSortMode = localStorage.getItem('sort_mode');
+                
+                if (savedSortMode) {
+                    sortMode = savedSortMode;
+                    document.querySelectorAll('.sort-btn').forEach(btn => btn.classList.remove('active'));
+                    const btn = document.getElementById('sort-' + sortMode);
+                    if (btn) btn.classList.add('active');
+                }
+                
+                if (saved) {
+                    const signals = JSON.parse(saved);
+                    
+                    signals.forEach(savedSignal => {
+                        for (let msgId in dbcData.messages) {
+                            const msg = dbcData.messages[msgId];
+                            const signal = msg.signals.find(s => 
+                                s.messageId === savedSignal.messageId && s.name === savedSignal.name);
+                            
+                            if (signal) {
+                                selectedSignals.push(signal);
+                                break;
+                            }
+                        }
+                    });
+                    
+                    displaySignals();
+                    
+                    if (selectedSignals.length > 0) {
+                        showStatus('✓ Restored ' + selectedSignals.length + ' selected signals', 'success');
+                    }
+                }
+            } catch(e) {
+                console.error('✗ Failed to load signals:', e);
+            }
+        }
+        
+        function startGraphing() {
+            if (selectedSignals.length === 0) {
+                showStatus('⚠️ Please select at least one signal!', 'error');
+                return;
+            }
+            
+            saveSelectedSignals();
+            
+            const width = 1400;
+            const height = 900;
+            const left = (screen.width - width) / 2;
+            const top = (screen.height - height) / 2;
+            
+            window.open(
+                '/graph-view',
+                'CAN_Graph_Viewer',
+                'width=' + width + ',height=' + height + ',left=' + left + ',top=' + top + ',resizable=yes,scrollbars=yes'
+            );
+            
+            showStatus('✓ Graph viewer opened in new window', 'success');
+        }
+        
+        function stopGraphing() {
+            showStatus('ℹ️ Use the stop button in the graph viewer window', 'info');
+        }
+        
+        function debugDBCInfo() {
+            console.log('=== DBC Debug Info ===');
+            console.log('Messages:', Object.keys(dbcData.messages).length);
+            console.log('Signals:', allSignals.length);
+            console.log('Value Tables:', Object.keys(dbcData.valueTables).length);
+            console.log('Selected Signals:', selectedSignals.length);
+            
+            console.log('\n=== Messages ===');
+            Object.values(dbcData.messages).forEach(msg => {
+                console.log('ID: 0x' + msg.id.toString(16).toUpperCase() + ' | ' + msg.name + ' | Signals: ' + msg.signals.length);
+            });
+            
+            console.log('\n=== Selected Signals ===');
+            selectedSignals.forEach((sig, idx) => {
+                console.log((idx + 1) + '. ' + sig.name + ' (ID: 0x' + sig.messageId.toString(16).toUpperCase() + ')');
+            });
+            
+            showStatus('✓ Debug info printed to console (F12)', 'info');
+        }
+        
+        function showStatus(message, type) {
+            const status = document.getElementById('status');
+            status.textContent = message;
+            status.className = 'status ' + type;
+            status.style.display = 'block';
+            setTimeout(() => { status.style.display = 'none'; }, 5000);
+        }
+        
+        // Drag & Drop
+        const uploadArea = document.querySelector('.upload-area');
+        ['dragenter', 'dragover', 'dragleave', 'drop'].forEach(eventName => {
+            uploadArea.addEventListener(eventName, e => {
+                e.preventDefault();
+                e.stopPropagation();
+            });
+        });
+        
+        ['dragenter', 'dragover'].forEach(eventName => {
+            uploadArea.addEventListener(eventName, () => {
+                uploadArea.style.borderColor = '#185a9d';
+                uploadArea.style.background = '#f0f9ff';
+            });
+        });
+        
+        ['dragleave', 'drop'].forEach(eventName => {
+            uploadArea.addEventListener(eventName, () => {
+                uploadArea.style.borderColor = '#43cea2';
+                uploadArea.style.background = 'white';
+            });
+        });
+        
+        uploadArea.addEventListener('drop', function(e) {
+            const file = e.dataTransfer.files[0];
+            if (file && file.name.endsWith('.dbc')) {
+                const reader = new FileReader();
+                reader.onload = function(ev) {
+                    parseDBCContent(ev.target.result);
+                    document.getElementById('dbc-status').textContent = '✓ ' + file.name;
+                    saveDBCToLocalStorage(ev.target.result, file.name);
+                };
+                reader.readAsText(file);
+            } else {
+                showStatus('⚠️ Please drop a .dbc file', 'error');
+            }
+        });
+        
+        // 페이지 로드 시 복원
+        window.addEventListener('load', function() {
+            if (loadDBCFromLocalStorage()) {
+                setTimeout(() => loadSelectedSignals(), 100);
+            }
+        });
+        
+        initWebSocket();
+    </script>
+</body>
+</html>
+)rawliteral";
+
+#endif
