diff --git a/graph.h b/graph.h
index 1474036..3b94814 100644
--- a/graph.h
+++ b/graph.h
@@ -1,36 +1,30 @@
-#ifndef GRAPH_H
-#define GRAPH_H
+#ifndef GRAPH_VIEWER_H
+#define GRAPH_VIEWER_H
 
-const char graph_html[] PROGMEM = R"rawliteral(
+const char graph_viewer_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</title>
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>CAN Signal Graph Viewer</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;
+            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); padding: 10px;
+            color: white;
+            overflow-x: hidden;
         }
         .header {
-            background: linear-gradient(135deg, #43cea2 0%, #185a9d 100%);
-            color: white;
-            padding: 20px;
+            background: linear-gradient(135deg, #667eea, #764ba2);
+            padding: 15px;
             text-align: center;
+            box-shadow: 0 2px 10px rgba(0,0,0,0.3);
         }
-        .header h1 { font-size: 1.8em; margin-bottom: 5px; }
+        .header h1 { font-size: 1.5em; }
+        .header p { font-size: 0.9em; opacity: 0.9; margin-top: 5px; }
+        
         /* ========== 통일된 네비게이션 ========== */
         .nav {
             background: #f8f9fa;
@@ -69,140 +63,26 @@ const char graph_html[] PROGMEM = R"rawliteral(
             background: white;
             font-weight: 600;
         }
-        .content { padding: 15px; }
-        
-        .dbc-upload {
-            background: #f8f9fa;
-            padding: 20px;
-            border-radius: 10px;
-            margin-bottom: 15px;
-        }
-        .upload-area {
-            border: 3px dashed #43cea2;
-            border-radius: 10px;
-            padding: 30px 20px;
-            text-align: center;
-            cursor: pointer;
-            transition: all 0.3s;
-        }
-        .upload-area:hover { background: #f0f9ff; border-color: #185a9d; }
-        .upload-area input { display: none; }
-        
-        .signal-selector {
-            background: #f8f9fa;
-            padding: 15px;
-            border-radius: 10px;
-            margin-bottom: 15px;
-        }
-        
-        .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: white;
-            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(200px, 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;
-        }
-        .signal-item:hover { border-color: #43cea2; transform: translateY(-2px); }
-        .signal-item.selected { border-color: #185a9d; background: #e3f2fd; }
-        .signal-name { font-weight: 600; color: #333; margin-bottom: 5px; font-size: 0.9em; }
-        .signal-info { font-size: 0.8em; color: white; line-height: 1.4; }
-        .highlight {
-            background-color: #ffeb3b;
-            padding: 2px 0;
-            font-weight: 600;
-        }
-        
         .controls {
+            background: #2a2a2a;
+            padding: 10px 15px;
             display: flex;
-            gap: 8px;
-            margin-bottom: 15px;
+            gap: 10px;
+            justify-content: center;
             flex-wrap: wrap;
+            box-shadow: 0 2px 5px rgba(0,0,0,0.2);
+        }
+        .control-group {
+            display: flex;
+            gap: 10px;
+            align-items: center;
+        }
+        .control-label {
+            font-size: 0.85em;
+            color: #aaa;
         }
         .btn {
-            padding: 10px 20px;
+            padding: 8px 20px;
             border: none;
             border-radius: 5px;
             font-size: 0.9em;
@@ -210,34 +90,68 @@ const char graph_html[] PROGMEM = R"rawliteral(
             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-info { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; }
+        .btn-warning { background: linear-gradient(135deg, #f2994a 0%, #f2c94c 100%); color: white; }
         .btn:hover { transform: translateY(-2px); box-shadow: 0 5px 15px rgba(0,0,0,0.3); }
+        .btn.active { 
+            box-shadow: inset 0 3px 5px rgba(0,0,0,0.3);
+            transform: translateY(0);
+        }
         
-        h2 {
-            color: #333;
-            margin: 20px 0 15px 0;
+        .graphs {
+            padding: 15px;
+            display: grid;
+            grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
+            gap: 15px;
+        }
+        .graph-container {
+            background: #2a2a2a;
+            padding: 15px;
+            border-radius: 10px;
+            border: 2px solid #3a3a3a;
+        }
+        .graph-header {
+            display: flex;
+            justify-content: space-between;
+            align-items: center;
+            margin-bottom: 10px;
             padding-bottom: 8px;
-            border-bottom: 3px solid #43cea2;
-            font-size: 1.3em;
+            border-bottom: 2px solid #43cea2;
         }
-        
-        .status { padding: 12px; background: #fff3cd; border-radius: 5px; margin-bottom: 15px; font-size: 0.9em; }
-        .status.success { background: #d4edda; color: #155724; }
-        .status.error { background: #f8d7da; color: #721c24; }
-        
-        .selection-info {
-            background: #e3f2fd;
-            padding: 12px 15px;
-            border-radius: 8px;
-            margin-bottom: 15px;
-            border-left: 4px solid #185a9d;
+        .graph-title {
+            font-size: 1em;
+            font-weight: 600;
+            color: #43cea2;
+        }
+        .graph-value {
+            font-size: 1.2em;
+            font-weight: 700;
+            color: #38ef7d;
+            font-family: 'Courier New', monospace;
+        }
+        canvas {
+            width: 100%;
+            height: 250px;
+            border: 1px solid #3a3a3a;
+            border-radius: 5px;
+            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); padding: 10px;
+        }
+        .status {
+            position: fixed;
+            top: 10px;
+            right: 10px;
+            padding: 10px 15px;
+            border-radius: 5px;
+            background: #2a2a2a;
+            border: 2px solid #43cea2;
             font-size: 0.9em;
-            color: #333;
+            z-index: 1000;
         }
-        .selection-info strong {
-            color: #185a9d;
+        .status.disconnected {
+            border-color: #eb3349;
+            background: #3a2a2a;
         }
         
         
@@ -305,565 +219,763 @@ const char graph_html[] PROGMEM = R"rawliteral(
     </style>
 </head>
 <body>
-    <div class="container">
-        <div class="header">
-            <h1>CAN Signal Graph</h1>
-            <p>Real-time Signal Visualization (Offline Mode)</p>
+    <div class="header">
+        <h1>Real-time CAN Signal Graphs (Scatter Mode)</h1>
+        <p>Viewing <span id="graph-count">0</span> signals</p>
+    </div>
+    
+    <div class="nav">
+        <a href="/">📊 Monitor</a>
+        <a href="/transmit">📤 Transmit</a>
+        <a href="/graph">📈 Graph</a>
+        <a href="/graph-view" class="active">📊 Graph View</a>
+        <a href="/settings">⚙️ Settings</a>
+        <a href="/serial">📟 Serial1</a>
+        <a href="/serial2">📟 Serial2</a>
+    </div>
+    
+    <div class="controls">
+        <div class="control-group">
+            <button class="btn btn-success" onclick="startGraphing()">Start</button>
+            <button class="btn btn-danger" onclick="stopGraphing()">Stop</button>
+            <button class="btn btn-danger" onclick="window.close()">Close</button>
         </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">📟 Serial1</a>
-            <a href="/serial2">📟 Serial2</a>
+        <div class="control-group">
+            <span class="control-label">X-Axis Scale:</span>
+            <button class="btn btn-info active" id="btn-index-mode" onclick="setScaleMode('index')">Index</button>
+            <button class="btn btn-info" id="btn-time-mode" onclick="setScaleMode('time')">Time-Based</button>
         </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)">
-                    <p style="font-size: 1.1em; margin-bottom: 8px;">Click to upload DBC</p>
-                    <p style="color: white; 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">
-                    <strong>Selected: <span id="selected-count">0</span> / 20</strong>
-                </div>
-                
-                <div class="controls">
-                    <button class="btn btn-success" onclick="startGraphing()">Start</button>
-                    <button class="btn btn-danger" onclick="stopGraphing()">Stop</button>
-                    <button class="btn btn-primary" onclick="clearSelection()">Clear</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, 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>
-                    </div>
-                    <div id="signal-list" class="signal-grid"></div>
-                </div>
-                
-                <div style="background: #e3f2fd; padding: 15px; border-radius: 8px; margin-top: 15px; border-left: 4px solid #185a9d;">
-                    <p style="color: #333; font-size: 0.9em; margin: 0;">
-                        <strong>ℹ️ Info:</strong> Click "Start" to open a new window with real-time graphs. 
-                        Your selected signals will be saved automatically.
-                    </p>
-                </div>
-            </div>
+        <div class="control-group">
+            <span class="control-label">X-Axis Range:</span>
+            <button class="btn btn-warning active" id="btn-range-10s" onclick="setRangeMode('10s')">10s Window</button>
+            <button class="btn btn-warning" id="btn-range-all" onclick="setRangeMode('all')">All Time</button>
+        </div>
+        <div class="control-group">
+            <span class="control-label">Sort by:</span>
+            <button class="btn btn-info active" id="btn-sort-selection" onclick="setSortMode('selection')">Selection Order</button>
+            <button class="btn btn-info" id="btn-sort-name-asc" onclick="setSortMode('name-asc')">Name (A→Z)</button>
+            <button class="btn btn-info" id="btn-sort-name-desc" onclick="setSortMode('name-desc')">Name (Z→A)</button>
+        </div>
+        <div class="control-group">
+            <button class="btn btn-success" onclick="downloadCSV()" style="background: linear-gradient(135deg, #2ecc71 0%, #27ae60 100%);">
+                📥 Download CSV
+            </button>
+            <button class="btn btn-danger" onclick="clearData()" style="background: linear-gradient(135deg, #e74c3c 0%, #c0392b 100%);">
+                🗑️ Clear Data
+            </button>
         </div>
     </div>
     
+    <div class="status" id="status">Connecting...</div>
+    
+    <div style="padding: 10px 15px; background: #2a2a2a; color: #aaa; font-size: 0.85em; display: flex; justify-content: space-between; align-items: center;">
+        <span>Data Points: <strong id="data-point-count" style="color: #43cea2;">0</strong></span>
+        <span>Recording Time: <strong id="recording-time" style="color: #43cea2;">0s</strong></span>
+        <span>Messages Received: <strong id="msg-received" style="color: #43cea2;">0</strong></span>
+    </div>
+    
+    <div class="graphs" id="graphs"></div>
+    
     <script>
         let ws;
-        let dbcData = {};
+        let charts = {};
+        let graphing = false;
+        let startTime = 0;
         let selectedSignals = [];
-        let allSignals = [];
-        let filteredSignals = [];
+        let dbcData = {};
+        let lastTimestamps = {};
         let sortMode = 'selection';
-        let searchQuery = '';
-        const MAX_SIGNALS = 20;
+        const MAX_DATA_POINTS = 60;
+        let scaleMode = 'index';
+        let rangeMode = '10s';
+        let totalMsgReceived = 0;
+        let lastCanCounts = {};  // ★ 각 CAN ID별 마지막 count 저장
+        
+        const COLORS = [
+            {line: '#FF6384', fill: 'rgba(255, 99, 132, 0.2)'},
+            {line: '#36A2EB', fill: 'rgba(54, 162, 235, 0.2)'},
+            {line: '#FFCE56', fill: 'rgba(255, 206, 86, 0.2)'},
+            {line: '#4BC0C0', fill: 'rgba(75, 192, 192, 0.2)'},
+            {line: '#9966FF', fill: 'rgba(153, 102, 255, 0.2)'},
+            {line: '#FF9F40', fill: 'rgba(255, 159, 64, 0.2)'},
+            {line: '#FF6384', fill: 'rgba(255, 99, 132, 0.2)'},
+            {line: '#4BC0C0', fill: 'rgba(75, 192, 192, 0.2)'},
+            {line: '#FFCE56', fill: 'rgba(255, 206, 86, 0.2)'},
+            {line: '#9966FF', fill: 'rgba(153, 102, 255, 0.2)'},
+            {line: '#36A2EB', fill: 'rgba(54, 162, 235, 0.2)'},
+            {line: '#FF9F40', fill: 'rgba(255, 159, 64, 0.2)'},
+            {line: '#E74C3C', fill: 'rgba(231, 76, 60, 0.2)'},
+            {line: '#3498DB', fill: 'rgba(52, 152, 219, 0.2)'},
+            {line: '#2ECC71', fill: 'rgba(46, 204, 113, 0.2)'},
+            {line: '#F39C12', fill: 'rgba(243, 156, 18, 0.2)'},
+            {line: '#9B59B6', fill: 'rgba(155, 89, 182, 0.2)'},
+            {line: '#1ABC9C', fill: 'rgba(26, 188, 156, 0.2)'},
+            {line: '#E67E22', fill: 'rgba(230, 126, 34, 0.2)'},
+            {line: '#95A5A6', fill: 'rgba(149, 165, 166, 0.2)'}
+        ];
+        
+        class SimpleChart {
+            constructor(canvas, signal, colorIndex) {
+                this.canvas = canvas;
+                this.ctx = canvas.getContext('2d');
+                this.signal = signal;
+                this.data = [];
+                this.times = [];
+                this.labels = [];
+                this.rawValues = [];
+                this.colors = COLORS[colorIndex % COLORS.length];
+                this.currentValue = 0;
+                this.currentText = '';
+                
+                this.resizeCanvas();
+                window.addEventListener('resize', () => this.resizeCanvas());
+            }
+            
+            resizeCanvas() {
+                const rect = this.canvas.getBoundingClientRect();
+                this.canvas.width = rect.width * window.devicePixelRatio;
+                this.canvas.height = rect.height * window.devicePixelRatio;
+                this.ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
+                this.width = rect.width;
+                this.height = rect.height;
+                this.draw();
+            }
+            
+            addData(value, time) {
+                this.data.push(value);
+                this.times.push(parseFloat(time));
+                this.labels.push(time);
+                this.rawValues.push(value);
+                this.currentValue = value;
+                
+                if (this.signal.valueTable && this.signal.valueTable[value] !== undefined) {
+                    this.currentText = this.signal.valueTable[value];
+                } else {
+                    this.currentText = '';
+                }
+                
+                if (scaleMode === 'index' && this.data.length > MAX_DATA_POINTS) {
+                    this.data.shift();
+                    this.times.shift();
+                    this.labels.shift();
+                    this.rawValues.shift();
+                }
+                
+                this.draw();
+            }
+            
+            getValueText(value) {
+                if (this.signal.valueTable && this.signal.valueTable[value] !== undefined) {
+                    return this.signal.valueTable[value];
+                }
+                return value.toFixed(2);
+            }
+            
+            draw() {
+                if (this.data.length === 0) return;
+                
+                const ctx = this.ctx;
+                const padding = 40;
+                const graphWidth = this.width - padding * 2;
+                const graphHeight = this.height - padding * 2;
+                
+                ctx.clearRect(0, 0, this.width, this.height);
+                
+                let displayData = [];
+                let displayTimes = [];
+                let displayLabels = [];
+                
+                if (rangeMode === '10s') {
+                    const currentTime = this.times[this.times.length - 1];
+                    for (let i = 0; i < this.times.length; i++) {
+                        if (currentTime - this.times[i] <= 10) {
+                            displayData.push(this.data[i]);
+                            displayTimes.push(this.times[i]);
+                            displayLabels.push(this.labels[i]);
+                        }
+                    }
+                } else {
+                    displayData = [...this.data];
+                    displayTimes = [...this.times];
+                    displayLabels = [...this.labels];
+                }
+                
+                if (displayData.length === 0) return;
+                
+                const minValue = Math.min(...displayData);
+                const maxValue = Math.max(...displayData);
+                const range = maxValue - minValue || 1;
+                
+                let minTime, maxTime, timeRange;
+                if (scaleMode === 'time') {
+                    minTime = displayTimes[0];
+                    maxTime = displayTimes[displayTimes.length - 1];
+                    timeRange = maxTime - minTime || 1;
+                }
+                
+                ctx.strokeStyle = '#444';
+                ctx.lineWidth = 1;
+                ctx.beginPath();
+                ctx.moveTo(padding, padding);
+                ctx.lineTo(padding, this.height - padding);
+                ctx.lineTo(this.width - padding, this.height - padding);
+                ctx.stroke();
+                
+                ctx.fillStyle = '#aaa';
+                ctx.font = '11px Arial';
+                ctx.textAlign = 'right';
+                
+                if (this.signal.valueTable) {
+                    const uniqueValues = [...new Set(displayData)].sort((a, b) => a - b);
+                    if (uniqueValues.length <= 5) {
+                        uniqueValues.forEach((val, idx) => {
+                            const y = this.height - padding - ((val - minValue) / range) * graphHeight;
+                            const text = this.getValueText(val);
+                            ctx.fillText(text, padding - 5, y + 5);
+                        });
+                    } else {
+                        ctx.fillText(this.getValueText(maxValue), padding - 5, padding + 5);
+                        ctx.fillText(this.getValueText(minValue), padding - 5, this.height - padding);
+                    }
+                } else {
+                    ctx.fillText(maxValue.toFixed(2), padding - 5, padding + 5);
+                    ctx.fillText(minValue.toFixed(2), padding - 5, this.height - padding);
+                }
+                
+                ctx.textAlign = 'center';
+                ctx.fillStyle = '#aaa';
+                ctx.font = '10px Arial';
+                if (displayLabels.length > 0) {
+                    ctx.fillText(displayLabels[0] + 's', padding, this.height - padding + 15);
+                    if (displayLabels.length > 1) {
+                        const lastIdx = displayLabels.length - 1;
+                        let xPos;
+                        if (scaleMode === 'time') {
+                            xPos = this.width - padding;
+                        } else {
+                            xPos = padding + (graphWidth / (MAX_DATA_POINTS - 1)) * Math.min(lastIdx, MAX_DATA_POINTS - 1);
+                        }
+                        ctx.fillText(displayLabels[lastIdx] + 's', xPos, this.height - padding + 15);
+                    }
+                }
+                ctx.fillText('Time (sec)', this.width / 2, this.height - 5);
+                
+                ctx.strokeStyle = '#333';
+                ctx.lineWidth = 1;
+                for (let i = 1; i < 5; i++) {
+                    const y = padding + (graphHeight / 5) * i;
+                    ctx.beginPath();
+                    ctx.moveTo(padding, y);
+                    ctx.lineTo(this.width - padding, y);
+                    ctx.stroke();
+                }
+                
+                if (displayData.length < 1) return;
+                
+                ctx.fillStyle = this.colors.line;
+                for (let i = 0; i < displayData.length; i++) {
+                    let x;
+                    
+                    if (scaleMode === 'time') {
+                        const timePos = (displayTimes[i] - minTime) / timeRange;
+                        x = padding + graphWidth * timePos;
+                    } else {
+                        x = padding + (graphWidth / (MAX_DATA_POINTS - 1)) * i;
+                    }
+                    
+                    const y = this.height - padding - ((displayData[i] - minValue) / range) * graphHeight;
+                    
+                    ctx.beginPath();
+                    ctx.arc(x, y, 5, 0, Math.PI * 2);
+                    ctx.fill();
+                    
+                    ctx.strokeStyle = '#fff';
+                    ctx.lineWidth = 1;
+                    ctx.stroke();
+                }
+            }
+        }
         
         function initWebSocket() {
-            ws = new WebSocket('ws://' + window.location.hostname + ':81');
+            const hostname = window.location.hostname;
+            ws = new WebSocket('ws://' + hostname + ':81');
             
             ws.onopen = function() {
                 console.log('WebSocket connected');
-                showStatus('Connected', 'success');
+                updateStatus('Connected', false);
             };
             
             ws.onclose = function() {
                 console.log('WebSocket disconnected');
-                showStatus('Disconnected - Reconnecting...', 'error');
+                updateStatus('Disconnected', true);
                 setTimeout(initWebSocket, 3000);
             };
             
             ws.onmessage = function(event) {
                 try {
                     const data = JSON.parse(event.data);
-                } catch(e) {
-                    console.error('Error parsing WebSocket data:', e);
-                }
-            };
-        }
-        
-        function loadDBCFile(event) {
-            const file = event.target.files[0];
-            if (!file) return;
-            
-            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 to localStorage:', e);
-            }
-        }
-        
-        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 from localStorage:', filename);
-                    return true;
-                }
-            } catch(e) {
-                console.error('Failed to load DBC from localStorage:', e);
-            }
-            return false;
-        }
-        
-        function parseDBCContent(content) {
-            dbcData = {messages: {}, valueTables: {}};
-            allSignals = [];
-            const lines = content.split('\n');
-            let currentMessage = null;
-            
-            // 먼저 VAL_ 정의를 파싱
-            for (let line of lines) {
-                line = line.trim();
-                
-                if (line.startsWith('VAL_ ')) {
-                    // VAL_ 형식: VAL_ <MessageID> <SignalName> <value> "<text>" ...;
-                    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];
-                        
-                        // Extended CAN ID 처리
-                        const normalizedMsgId = (msgId & 0x80000000) ? (msgId & 0x1FFFFFFF) : msgId;
-                        
-                        const key = normalizedMsgId + '_' + sigName;
-                        dbcData.valueTables[key] = {};
-                        
-                        // 값-텍스트 쌍 파싱
-                        const valueMatches = valuesStr.matchAll(/(\d+)\s+"([^"]+)"/g);
-                        for (let vm of valueMatches) {
-                            dbcData.valueTables[key][parseInt(vm[1])] = vm[2];
+                    
+                    // ★★★ 핵심 수정: 'update' 타입도 처리
+                    if (graphing) {
+                        if (data.type === 'canBatch') {
+                            processCANData(data.messages);
+                        } else if (data.type === 'update' || data.type === 'status') {
+                            // 서버가 보내는 update 타입의 messages 배열 처리
+                            if (data.messages && data.messages.length > 0) {
+                                processCANDataFromUpdate(data.messages);
+                            }
                         }
-                        
-                        console.log('Parsed Value Table: ' + key, dbcData.valueTables[key]);
                     }
+                } catch(e) {
+                    console.error('Error:', e);
                 }
-            }
-            
-            // 메시지와 시그널 파싱
-            for (let line of lines) {
-                line = line.trim();
+            };
+        }
+        
+        function updateStatus(text, isError) {
+            const status = document.getElementById('status');
+            status.textContent = text;
+            status.className = 'status' + (isError ? ' disconnected' : '');
+        }
+        
+        function loadData() {
+            try {
+                const signals = localStorage.getItem('selected_signals');
+                const dbc = localStorage.getItem('dbc_content');
+                const savedSortMode = localStorage.getItem('sort_mode');
                 
-                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,
+                if (!signals || !dbc) {
+                    alert('No signals selected. Please select signals first.');
+                    window.close();
+                    return false;
+                }
+                
+                if (savedSortMode) {
+                    sortMode = savedSortMode;
+                }
+                
+                selectedSignals = JSON.parse(signals);
+                
+                dbcData = {messages: {}};
+                selectedSignals.forEach(sig => {
+                    if (!dbcData.messages[sig.messageId]) {
+                        dbcData.messages[sig.messageId] = {
+                            id: sig.messageId,
                             signals: []
                         };
-                        dbcData.messages[id] = currentMessage;
-                        
-                        console.log('Parsed 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
-                        };
-                        
-                        // Value Table 연결
-                        const vtKey = currentMessage.id + '_' + signalName;
-                        if (dbcData.valueTables[vtKey]) {
-                            signal.valueTable = dbcData.valueTables[vtKey];
-                            console.log('  Signal with value table: ' + signalName, signal.valueTable);
-                        }
-                        
-                        currentMessage.signals.push(signal);
-                        allSignals.push(signal);
-                        
-                        console.log('  Signal: ' + signal.name + ' [' + signal.startBit + '|' + signal.bitLength + '] Unit: ' + signal.unit);
-                    }
-                }
-            }
-            
-            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;
+                    dbcData.messages[sig.messageId].signals.push(sig);
                 });
                 
-                const searchInfo = document.getElementById('search-info');
-                searchInfo.textContent = 'Showing ' + filteredSignals.length + ' of ' + allSignals.length + ' signals';
-                searchInfo.style.display = 'block';
+                console.log('Loaded', selectedSignals.length, 'signals');
+                
+                selectedSignals.forEach(sig => {
+                    if (sig.valueTable) {
+                        console.log('Signal with Value Table:', sig.name, sig.valueTable);
+                    }
+                });
+                
+                return true;
+            } catch(e) {
+                console.error('Failed to load data:', e);
+                alert('Failed to load signal data');
+                window.close();
+                return false;
             }
-            
-            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 sortSignalsForDisplay() {
+            if (sortMode === 'name-asc') {
+                return [...selectedSignals].sort((a, b) => a.name.localeCompare(b.name));
+            } else if (sortMode === 'name-desc') {
+                return [...selectedSignals].sort((a, b) => b.name.localeCompare(a.name));
+            } else {
+                return selectedSignals;
+            }
         }
         
         function setSortMode(mode) {
             sortMode = mode;
             
-            document.querySelectorAll('.sort-btn').forEach(btn => btn.classList.remove('active'));
-            document.getElementById('sort-' + mode).classList.add('active');
+            document.querySelectorAll('[id^="btn-sort-"]').forEach(btn => btn.classList.remove('active'));
+            document.getElementById('btn-sort-' + mode).classList.add('active');
             
-            displaySignals();
+            createGraphs();
             
             console.log('Sort mode changed to:', 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 {
-                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 = '';
+        function createGraphs() {
+            const graphsDiv = document.getElementById('graphs');
+            graphsDiv.innerHTML = '';
+            charts = {};
             
-            const sortedSignals = sortSignals([...filteredSignals]);
+            const sortedSignals = sortSignalsForDisplay();
             
-            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';
+            sortedSignals.forEach((signal, index) => {
+                const container = document.createElement('div');
+                container.className = 'graph-container';
                 
-                if (isSignalSelected(signal)) {
-                    item.classList.add('selected');
-                }
+                const canvas = document.createElement('canvas');
+                canvas.id = 'chart-' + index;
                 
-                item.onclick = () => toggleSignal(signal, item);
-                
-                const canIdHex = '0x' + signal.messageId.toString(16).toUpperCase().padStart(3, '0');
-                
-                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">' +
-                    'CAN ID: ' + highlightedId + ' (' + highlightedMsgName + ')<br>' +
-                    'Bit: ' + signal.startBit + '|' + signal.bitLength + ' | ' + unitText +
+                container.innerHTML = 
+                    '<div class="graph-header">' +
+                        '<div class="graph-title">' + signal.name + ' (0x' + signal.messageId.toString(16).toUpperCase() + ')' +
+                        (signal.unit ? ' [' + signal.unit + ']' : '') + '</div>' +
+                        '<div class="graph-value" id="value-' + index + '">-</div>' +
                     '</div>';
                 
-                signalList.appendChild(item);
+                container.appendChild(canvas);
+                graphsDiv.appendChild(container);
+                
+                charts[index] = new SimpleChart(canvas, signal, index);
             });
             
-            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('Max ' + MAX_SIGNALS + ' signals!', '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();
-            }
-        }
-        
-        function saveSelectedSignals() {
-            try {
-                localStorage.setItem('selected_signals', JSON.stringify(selectedSignals));
-                localStorage.setItem('sort_mode', sortMode);
-                console.log('Saved', selectedSignals.length, 'signals with sort mode:', sortMode);
-            } catch(e) {
-                console.error('Failed to save selected 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'));
-                    document.getElementById('sort-' + sortMode).classList.add('active');
-                }
-                
-                if (saved) {
-                    const signals = JSON.parse(saved);
-                    
-                    signals.forEach(savedSignal => {
-                        let found = false;
-                        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);
-                                found = true;
-                                break;
-                            }
-                        }
-                    });
-                    
-                    displaySignals();
-                    
-                    if (selectedSignals.length > 0) {
-                        showStatus('Restored ' + selectedSignals.length + ' selected signals', 'success');
-                    }
-                }
-            } catch(e) {
-                console.error('Failed to load selected signals:', e);
-            }
+            document.getElementById('graph-count').textContent = sortedSignals.length;
         }
         
         function startGraphing() {
-            if (selectedSignals.length === 0) {
-                showStatus('Select at least one signal!', 'error');
-                return;
+            if (!graphing) {
+                graphing = true;
+                startTime = Date.now();
+                lastTimestamps = {};
+                updateStatus('Graphing...', false);
+                console.log('Started graphing at', new Date().toISOString());
             }
-            
-            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('Use the stop button in the graph viewer window', 'error');
+            graphing = false;
+            updateStatus('Stopped', false);
+            console.log('Stopped graphing');
         }
         
-        function debugDBCInfo() {
-            console.log('=== DBC Debug Info ===');
-            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);
+        function setScaleMode(mode) {
+            scaleMode = mode;
             
-            console.log('\n=== Value Tables ===');
-            for (let key in dbcData.valueTables) {
-                console.log(key + ':', dbcData.valueTables[key]);
-            }
+            document.getElementById('btn-index-mode').classList.toggle('active', mode === 'index');
+            document.getElementById('btn-time-mode').classList.toggle('active', mode === 'time');
             
-            console.log('\n=== Messages ===');
-            Object.values(dbcData.messages).forEach(msg => {
-                console.log('\nMessage: ' + msg.name);
-                console.log('  ID: ' + msg.id + ' (0x' + msg.id.toString(16).toUpperCase() + ')');
-                console.log('  DLC: ' + msg.dlc);
-                console.log('  Signals: ' + msg.signals.length);
+            Object.values(charts).forEach(chart => chart.draw());
+            
+            console.log('Scale mode changed to:', mode);
+        }
+        
+        function setRangeMode(mode) {
+            rangeMode = mode;
+            
+            document.getElementById('btn-range-10s').classList.toggle('active', mode === '10s');
+            document.getElementById('btn-range-all').classList.toggle('active', mode === 'all');
+            
+            Object.values(charts).forEach(chart => chart.draw());
+            
+            console.log('Range mode changed to:', mode);
+        }
+        
+        // ★★★ 새로운 함수: update 타입 메시지 처리
+        // 서버가 보내는 형식: {id: 숫자, dlc: 숫자, data: [배열], count: 숫자}
+        // ★★★ count가 증가한 경우에만 그래프에 데이터 추가
+        function processCANDataFromUpdate(messages) {
+            const elapsedTime = ((Date.now() - startTime) / 1000).toFixed(1);
+            const sortedSignals = sortSignalsForDisplay();
+            
+            let processedCount = 0;
+            
+            messages.forEach(canMsg => {
+                // id가 숫자로 오는 경우 처리
+                let msgId = canMsg.id;
+                if (typeof msgId === 'string') {
+                    msgId = parseInt(msgId.replace('0x', ''), 16);
+                }
                 
-                msg.signals.forEach(sig => {
-                    console.log('    - ' + sig.name + ': ' + sig.startBit + '|' + sig.bitLength + ' [' + sig.unit + ']');
-                    if (sig.valueTable) {
-                        console.log('      Value Table:', sig.valueTable);
+                // Extended CAN ID 처리 (bit 31 제거)
+                if (msgId & 0x80000000) {
+                    msgId = msgId & 0x1FFFFFFF;
+                }
+                
+                // ★ count가 증가한 경우에만 처리 (새로운 CAN 메시지가 있을 때만)
+                const prevCount = lastCanCounts[msgId] || 0;
+                const currentCount = canMsg.count || 0;
+                
+                if (currentCount <= prevCount) {
+                    // count가 증가하지 않았으면 스킵
+                    return;
+                }
+                
+                // count 업데이트
+                lastCanCounts[msgId] = currentCount;
+                totalMsgReceived++;
+                
+                // data가 배열로 오는 경우 HEX 문자열로 변환
+                let hexData = '';
+                if (Array.isArray(canMsg.data)) {
+                    hexData = canMsg.data.map(b => b.toString(16).padStart(2, '0')).join('');
+                } else if (typeof canMsg.data === 'string') {
+                    hexData = canMsg.data.replace(/\s/g, '');
+                }
+                
+                sortedSignals.forEach((signal, index) => {
+                    if (signal.messageId === msgId && charts[index]) {
+                        try {
+                            const value = decodeSignalFromHex(signal, hexData);
+                            
+                            charts[index].addData(value, elapsedTime);
+                            
+                            const valueDiv = document.getElementById('value-' + index);
+                            if (valueDiv) {
+                                if (signal.valueTable && signal.valueTable[value] !== undefined) {
+                                    valueDiv.textContent = signal.valueTable[value];
+                                } else {
+                                    valueDiv.textContent = value.toFixed(2) + (signal.unit ? ' ' + signal.unit : '');
+                                }
+                            }
+                            
+                            processedCount++;
+                        } catch(e) {
+                            console.error('Error decoding signal ' + signal.name + ':', e);
+                        }
                     }
                 });
             });
             
-            showStatus('Debug info printed to console (F12)', 'success');
+            if (processedCount > 0) {
+                console.log('Added', processedCount, 'new data points from update');
+            }
+            
+            updateStatistics();
         }
         
-        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);
+        // 기존 canBatch 처리 함수 (문자열 형식 데이터용)
+        function processCANData(messages) {
+            const elapsedTime = ((Date.now() - startTime) / 1000).toFixed(1);
+            const sortedSignals = sortSignalsForDisplay();
+            
+            console.log('Processing', messages.length, 'messages at time', elapsedTime + 's');
+            
+            let processedCount = 0;
+            totalMsgReceived += messages.length;
+            
+            messages.forEach(canMsg => {
+                const idStr = (canMsg.id || '').toString().replace(/\s/g, '').toUpperCase();
+                let msgId = parseInt(idStr.replace('0X', ''), 16);
+                
+                if (msgId & 0x80000000) {
+                    msgId = msgId & 0x1FFFFFFF;
+                }
+                
+                const timestamp = canMsg.timestamp;
+                
+                sortedSignals.forEach((signal, index) => {
+                    if (signal.messageId === msgId && charts[index]) {
+                        try {
+                            const value = decodeSignal(signal, canMsg.data);
+                            
+                            charts[index].addData(value, elapsedTime);
+                            
+                            const valueDiv = document.getElementById('value-' + index);
+                            if (valueDiv) {
+                                if (signal.valueTable && signal.valueTable[value] !== undefined) {
+                                    valueDiv.textContent = signal.valueTable[value];
+                                } else {
+                                    valueDiv.textContent = value.toFixed(2) + (signal.unit ? ' ' + signal.unit : '');
+                                }
+                            }
+                            
+                            processedCount++;
+                        } catch(e) {
+                            console.error('Error decoding signal ' + signal.name + ':', e);
+                        }
+                    }
+                });
+            });
+            
+            if (processedCount > 0) {
+                console.log('Added', processedCount, 'new data points');
+            }
+            
+            updateStatistics();
         }
         
-        const uploadArea = document.querySelector('.upload-area');
-        ['dragenter', 'dragover', 'dragleave', 'drop'].forEach(eventName => {
-            uploadArea.addEventListener(eventName, e => {
-                e.preventDefault();
-                e.stopPropagation();
+        function updateStatistics() {
+            let totalDataPoints = 0;
+            Object.values(charts).forEach(chart => {
+                totalDataPoints += chart.data.length;
             });
-        });
+            
+            document.getElementById('data-point-count').textContent = totalDataPoints;
+            document.getElementById('msg-received').textContent = totalMsgReceived;
+            
+            const recordingTime = ((Date.now() - startTime) / 1000).toFixed(1);
+            document.getElementById('recording-time').textContent = recordingTime + 's';
+        }
         
-        ['dragenter', 'dragover'].forEach(eventName => {
-            uploadArea.addEventListener(eventName, () => {
-                uploadArea.style.borderColor = '#185a9d';
-                uploadArea.style.background = '#f0f9ff';
-            });
-        });
+        // ★ HEX 문자열에서 바이트 배열로 변환 후 디코딩
+        function decodeSignalFromHex(signal, hexData) {
+            const bytes = [];
+            const cleanHex = hexData.toUpperCase();
+            for (let i = 0; i < cleanHex.length && i < 16; i += 2) {
+                bytes.push(parseInt(cleanHex.substring(i, i + 2), 16));
+            }
+            while (bytes.length < 8) bytes.push(0);
+            
+            return decodeSignalFromBytes(signal, bytes);
+        }
         
-        ['dragleave', 'drop'].forEach(eventName => {
-            uploadArea.addEventListener(eventName, () => {
-                uploadArea.style.borderColor = '#43cea2';
-                uploadArea.style.background = '';
-            });
-        });
+        function decodeSignal(signal, hexData) {
+            const bytes = [];
+            
+            if (typeof hexData === 'string') {
+                const cleanHex = hexData.replace(/\s/g, '').toUpperCase();
+                for (let i = 0; i < cleanHex.length && i < 16; i += 2) {
+                    bytes.push(parseInt(cleanHex.substring(i, i + 2), 16));
+                }
+            } else if (Array.isArray(hexData)) {
+                bytes.push(...hexData);
+            }
+            
+            while (bytes.length < 8) bytes.push(0);
+            
+            return decodeSignalFromBytes(signal, bytes);
+        }
         
-        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;
+        function decodeSignalFromBytes(signal, bytes) {
+            let rawValue = 0;
+            
+            if (signal.byteOrder === 'intel') {
+                for (let i = 0; i < signal.bitLength; i++) {
+                    const bitPos = signal.startBit + i;
+                    const byteIdx = Math.floor(bitPos / 8);
+                    const bitIdx = bitPos % 8;
                     
-                    saveDBCToLocalStorage(ev.target.result, file.name);
-                };
-                reader.readAsText(file);
+                    if (byteIdx < bytes.length) {
+                        const bit = (bytes[byteIdx] >> bitIdx) & 1;
+                        rawValue |= (bit << i);
+                    }
+                }
+            } else {
+                for (let i = 0; i < signal.bitLength; i++) {
+                    const bitPos = signal.startBit - i;
+                    const byteIdx = Math.floor(bitPos / 8);
+                    const bitIdx = 7 - (bitPos % 8);
+                    
+                    if (byteIdx < bytes.length && byteIdx >= 0) {
+                        const bit = (bytes[byteIdx] >> bitIdx) & 1;
+                        rawValue |= (bit << (signal.bitLength - 1 - i));
+                    }
+                }
             }
-        });
-        
-        window.addEventListener('load', function() {
-            if (loadDBCFromLocalStorage()) {
-                setTimeout(() => loadSelectedSignals(), 100);
+            
+            if (signal.signed && (rawValue & (1 << (signal.bitLength - 1)))) {
+                rawValue -= (1 << signal.bitLength);
             }
-        });
+            
+            return rawValue * signal.factor + signal.offset;
+        }
         
-        initWebSocket();
+        function downloadCSV() {
+            if (Object.keys(charts).length === 0) {
+                alert('No data to download!');
+                return;
+            }
+            
+            let csvContent = 'Time(s)';
+            const sortedSignals = sortSignalsForDisplay();
+            
+            sortedSignals.forEach(signal => {
+                const unit = signal.unit ? ' [' + signal.unit + ']' : '';
+                csvContent += ',' + signal.name + unit;
+                
+                if (signal.valueTable) {
+                    csvContent += ',' + signal.name + '_Text';
+                }
+            });
+            csvContent += '\n';
+            
+            let maxLength = 0;
+            Object.values(charts).forEach(chart => {
+                if (chart.labels.length > maxLength) {
+                    maxLength = chart.labels.length;
+                }
+            });
+            
+            for (let i = 0; i < maxLength; i++) {
+                let row = '';
+                let timeValue = '';
+                
+                sortedSignals.forEach((signal, index) => {
+                    const chart = charts[index];
+                    if (chart && chart.labels[i] !== undefined) {
+                        if (timeValue === '') {
+                            timeValue = chart.labels[i];
+                        }
+                        const value = chart.data[i];
+                        row += ',' + value.toFixed(6);
+                        
+                        if (signal.valueTable) {
+                            const text = signal.valueTable[value] !== undefined ? 
+                                        signal.valueTable[value] : '';
+                            row += ',"' + text + '"';
+                        }
+                    } else {
+                        row += ',';
+                        if (signal.valueTable) {
+                            row += ',';
+                        }
+                    }
+                });
+                
+                if (timeValue !== '') {
+                    csvContent += timeValue + row + '\n';
+                }
+            }
+            
+            const blob = new Blob([csvContent], { type: 'text/csv;charset=utf-8;' });
+            const link = document.createElement('a');
+            const url = URL.createObjectURL(blob);
+            
+            const timestamp = new Date().toISOString().replace(/[:.]/g, '-').slice(0, -5);
+            link.setAttribute('href', url);
+            link.setAttribute('download', 'can_signals_' + timestamp + '.csv');
+            link.style.visibility = 'hidden';
+            
+            document.body.appendChild(link);
+            link.click();
+            document.body.removeChild(link);
+            
+            console.log('CSV downloaded with ' + maxLength + ' data points');
+        }
+        
+        function clearData() {
+            if (!confirm('Clear all recorded data? This cannot be undone.')) {
+                return;
+            }
+            
+            Object.values(charts).forEach(chart => {
+                chart.data = [];
+                chart.times = [];
+                chart.labels = [];
+                chart.rawValues = [];
+                chart.currentValue = 0;
+                chart.currentText = '';
+                chart.draw();
+            });
+            
+            lastTimestamps = {};
+            lastCanCounts = {};  // ★ count 기록도 초기화
+            startTime = Date.now();
+            totalMsgReceived = 0;
+            
+            updateStatistics();
+            
+            console.log('All data cleared');
+        }
+        
+        if (loadData()) {
+            createGraphs();
+            initWebSocket();
+            startGraphing();
+        }
     </script>
 </body>
 </html>
