Fix BullTron MOS refresh ordering

tests/test_bulltron_gui.py

@@ -121,6 +121,29 @@ class BullTronParserTest(unittest.TestCase):
         self.assertTrue(state.control_charge_mos)
         self.assertFalse(state.control_discharge_mos)
 
+    def test_direct_mos_control_read_uses_register_context(self):
+        state = DeviceState()
+        payload = b"\x00\x00\x00\x01"
+        body = bytes([0xD2, 0x03, len(payload)]) + payload
+        from bulltron_gui import crc16_modbus_swapped
+
+        frame = body + crc16_modbus_swapped(body).to_bytes(2, "big")
+        decode_response(frame, state, 0x00A5)
+
+        self.assertFalse(state.control_charge_mos)
+        self.assertTrue(state.control_discharge_mos)
+
+    def test_four_byte_non_mos_read_still_decodes_production_date(self):
+        state = DeviceState()
+        payload = b"\x19\x01\x01\x00"
+        body = bytes([0xD2, 0x03, len(payload)]) + payload
+        from bulltron_gui import crc16_modbus_swapped
+
+        frame = body + crc16_modbus_swapped(body).to_bytes(2, "big")
+        decode_response(frame, state, 0x00C9)
+
+        self.assertEqual(state.production_date, "2025-01-01")
+
     def test_system_mos_write_registers(self):
         self.assertEqual(write_single_frame(0x00A5, 1).hex().upper()[:8], "D20600A5")
         self.assertEqual(write_single_frame(0x00A6, 0).hex().upper()[:8], "D20600A6")