.. _flange_serial_read:

flange_serial_read
------------------------------------------
This function receives serial data from the **flange serial port** in the robot controller. |br|
The port parameter is **only available in the new flange version (v2).**

**Definition** |br|
``DRFLEx.h`` within class `CDRFLEx`, public section

.. code-block:: cpp

    LPFLANGE_SER_RXD_INFO_EX flange_serial_read(float fTimeout = -1, int nPort = 1)
    {
        return _flange_serial_read(_rbtCtrl, fTimeout, nPort);
    };

**Parameter**

.. list-table::
   :widths: 20 20 20 40
   :header-rows: 1

   * - **Parameter Name**
     - **Data Type**
     - **Default Value**
     - **Description**
   * - fTimeout
     - float
     - -1
     - Timeout value in seconds. |br|
       A value of **-1** means the function will **wait indefinitely** for incoming data. |br|
       The call returns when data arrives or when fTimeout elapses.
   * - nPort
     - int
     - 1
     - **Port number for flange serial interface** |br|
       1: X1, 2: X2 (X2 only on M/H models)

**Return**

.. list-table::
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   :header-rows: 1

   * - **Value**
     - **Description**
   * - :ref:`FLANGE_SER_RXD_INFO_EX <struct_flange_ser_rxd_info_ex>`
     - Refer to the Definition of Structure

.. note::

   The returned pointer refers to storage in the CDRFLEx object that other DRFL calls and every reconnect reuse; copy the structure before making another DRFL call. The 3-argument ``ikin`` returns its result in storage shared by all CDRFLEx objects in the process instead; see :ref:`ikin <ikin>`. Except for ``get_user_home``, the pointer is never NULL; do not use a NULL check to detect failure.

   The flange board revision used by the flange serial and flange I/O functions is read at open_connection.

**Example**

.. code-block:: cpp

    char buf[] = "test123";
    Drfl.flange_serial_open(1, 115200);
    Drfl.flange_serial_write(7, buf, 1);

    LPFLANGE_SER_RXD_INFO_EX temp = Drfl.flange_serial_read(4.5, 1);
    printf("Serial read : %.*s\n", temp->_iSize, (const char*)temp->_cRxd);
    printf("Serial cnt  : %d\n", temp->_iSize);

    Drfl.flange_serial_close(1);

This example opens the flange serial port, sends the string `"test123"`,  
waits up to **4.5 seconds** for a response, and prints the received data  
and byte count using the returned structure.