.. _manual_flange_serial_open:

flange_serial_open (Manual Mode)
------------------------------------------
This section explains how to use :ref:`flange_serial_open <flange_serial_open>` during **Manual (Teach)** operations  
to **establish serial communication** between the robot’s flange port and an external device such as a **gripper, sensor, or tool controller**.

**Typical usage**

- Manually send/receive data to verify tool communication during setup.  
- Check device response and signal integrity before automatic program execution.

.. Note::

    - After opening, you can use :ref:`flange_serial_write <flange_serial_write>` and :ref:`flange_serial_read <manual_flange_serial_read>` for data exchange.
    - The flange board revision used by the flange serial and flange I/O functions is read at open_connection.

**Example: Open flange serial port and verify communication**

.. code-block:: cpp

   // Preconditions:
   // - Connection established (open_connection)
   // - Manual (Teach) mode active
   // - External serial device connected to flange X1

   // 1) Open the flange serial port
   bool opened = drfl.flange_serial_open(
       1,                    // Port number
       115200,               // Baud rate
       BYTE_SIZE_EIGHTBITS,  // Data bits
       PARITY_CHECK_NONE,    // Parity
       STOPBITS_ONE          // Stop bits
   );

   if (!opened) {
       printf("[Flange] Failed to open X1.\n");
       return -1;
   }
   printf("[Flange] X1 opened successfully.\n");

   // 2) (Optional) Write / read test data
   // char cmd[] = "STATUS?";
   // drfl.flange_serial_write((int)strlen(cmd), cmd, 1);
   // LPFLANGE_SER_RXD_INFO_EX rx = drfl.flange_serial_read(3.0f, 1);
   // printf("Response: %.*s\n", rx->_iSize, (const char*)rx->_cRxd);

   // 3) Close after test
   drfl.flange_serial_close(1);
   printf("[Flange] X1 closed.\n");

**Tips**

- Match **baudrate, parity, and stop bits** exactly with the device’s serial configuration.  
- Use short test messages (e.g., 8–32 bytes) to confirm stable communication.  
- If open fails, check cable wiring (TX/RX swap) or ensure the port is not already active.  
- Always close the port using :ref:`flange_serial_close <flange_serial_close>` before reopening or switching devices.