diff --git a/lib/bluetooth/devices/elite/elite_square.dart b/lib/bluetooth/devices/elite/elite_square.dart
index faccf40..0e6d9bf 100644
--- a/lib/bluetooth/devices/elite/elite_square.dart
+++ b/lib/bluetooth/devices/elite/elite_square.dart
@@ -40,11 +40,11 @@ class EliteSquare extends BluetoothDevice {
       actionStreamInternal.add(LogNotification('Received $fullValue - vs $currentValue (last: $_lastValue)'));
 
       if (_lastValue != null) {
-        final currentRelevantPart = fullValue.length >= 19
-            ? fullValue.substring(6, fullValue.length - 13)
+        final currentRelevantPart = fullValue.length >= 14
+            ? fullValue.substring(6, 14)
             : fullValue.substring(6);
-        final lastRelevantPart = _lastValue!.length >= 19
-            ? _lastValue!.substring(6, _lastValue!.length - 13)
+        final lastRelevantPart = _lastValue!.length >= 14
+            ? _lastValue!.substring(6, 14)
             : _lastValue!.substring(6);
 
         if (currentRelevantPart != lastRelevantPart) {
diff --git a/test/elite_square_test.dart b/test/elite_square_test.dart
new file mode 100644
index 0000000..732fc9c
--- /dev/null
+++ b/test/elite_square_test.dart
@@ -0,0 +1,132 @@
+import 'package:flutter_test/flutter_test.dart';
+
+// Helper function matching the Elite Square implementation
+// Extracts the 8-character button code from positions 6-14 of the hex string
+String extractButtonCode(String hexValue) {
+  if (hexValue.length >= 14) {
+    return hexValue.substring(6, 14);
+  }
+  return hexValue.substring(6);
+}
+
+String bytesToHex(List<int> bytes) {
+  return bytes.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join();
+}
+
+void main() {
+  group('Elite Square Button Detection Tests', () {
+    test('Should extract correct button code from hex string', () {
+      // Test with actual dump data
+      expect(extractButtonCode('030153000000020318f40101'), equals('00000002'));
+      expect(extractButtonCode('030153000000010318f40101'), equals('00000001'));
+      expect(extractButtonCode('030153000004000318f40101'), equals('00000400'));
+      expect(extractButtonCode('030153000001000318f40101'), equals('00000100'));
+      expect(extractButtonCode('030153000008000318f40101'), equals('00000800'));
+      expect(extractButtonCode('030153000002000318f40101'), equals('00000200'));
+      expect(extractButtonCode('030153000000000318f40101'), equals('00000000'));
+    });
+
+    test('Should detect button changes correctly', () {
+      // Test that button code extraction is consistent for comparison
+      final idleState = '030153000000000318f40101';
+      final buttonPressed = '030153000000020318f40101';
+      
+      final idleCode = extractButtonCode(idleState);
+      final pressedCode = extractButtonCode(buttonPressed);
+
+      expect(idleCode, equals('00000000'));
+      expect(pressedCode, equals('00000002'));
+      expect(idleCode != pressedCode, isTrue);
+    });
+
+    test('Should handle button release correctly', () {
+      // Simulate button press and release
+      final states = [
+        '030153000000000318f40101', // idle
+        '030153000000020318f40101', // button pressed
+        '030153000000000318f40101', // button released (back to idle)
+      ];
+
+      final parts = states.map(extractButtonCode).toList();
+      
+      expect(parts[0], equals('00000000')); // idle
+      expect(parts[1], equals('00000002')); // pressed
+      expect(parts[2], equals('00000000')); // released
+      
+      // Verify state transitions
+      expect(parts[0] != parts[1], isTrue);  // idle -> pressed
+      expect(parts[1] != parts[2], isTrue);  // pressed -> released
+      expect(parts[0] == parts[2], isTrue);  // back to idle
+    });
+
+    test('Should handle all button codes from mapping', () {
+      // Test all button codes from the mapping
+      final buttonCodes = {
+        "00000200": "up",
+        "00000100": "left",
+        "00000800": "down",
+        "00000400": "right",
+        "00002000": "x",
+        "00001000": "square",
+        "00008000": "campagnoloLeft",
+        "00004000": "leftBrake",
+        "00000002": "leftShift1",
+        "00000001": "leftShift2",
+        "02000000": "y",
+        "01000000": "a",
+        "08000000": "b",
+        "04000000": "z",
+        "20000000": "circle",
+        "10000000": "triangle",
+        "80000000": "campagnoloRight",
+        "40000000": "rightBrake",
+        "00020000": "rightShift1",
+        "00010000": "rightShift2",
+      };
+
+      // Verify all button codes are 8 characters
+      for (final code in buttonCodes.keys) {
+        expect(code.length, equals(8), reason: 'Button code $code should be 8 characters');
+      }
+    });
+
+    test('Should convert bytes to hex correctly', () {
+      // Test with sample data from the dump
+      // 030153000000020318f40101 = [0x03, 0x01, 0x53, 0x00, 0x00, 0x00, 0x02, 0x03, 0x18, 0xf4, 0x01, 0x01]
+      final bytes = [0x03, 0x01, 0x53, 0x00, 0x00, 0x00, 0x02, 0x03, 0x18, 0xf4, 0x01, 0x01];
+      final hex = bytesToHex(bytes);
+      
+      expect(hex, equals('030153000000020318f40101'));
+    });
+
+    test('Should handle edge cases', () {
+      // Test with short strings
+      expect(extractButtonCode('0123456789'), equals('6789'));
+      expect(extractButtonCode('01234567'), equals('67'));
+      
+      // Test with exact length (14 chars extracts positions 6-14)
+      expect(extractButtonCode('01234567890123'), equals('67890123'));
+      
+      // Test strings shorter than 14 extract from position 6 to end
+      expect(extractButtonCode('0123456789ABC'), equals('6789ABC'));
+    });
+  });
+
+  group('Elite Square Protocol Tests', () {
+    test('Should recognize button press pattern', () {
+      // According to the dump, the pattern is:
+      // Base: 030153000000000318f40101
+      // Byte positions 6-13 (8 chars) change to indicate button
+      
+      final baseHex = '030153000000000318f40101';
+      final buttonHex = '030153000000020318f40101';
+      
+      // Extract the button part (positions 6-14)
+      final baseButton = baseHex.substring(6, 14);
+      final pressedButton = buttonHex.substring(6, 14);
+      
+      expect(baseButton, equals('00000000'));
+      expect(pressedButton, equals('00000002'));
+    });
+  });
+}