pw_stream_uart_mcuxpresso/docs.rst


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.. _module-pw_stream_uart_mcuxpresso:

=========================
pw_stream_uart_mcuxpresso
=========================
``pw_stream_uart_mcuxpresso`` implements the ``pw_stream`` interface for reading
and writing to a UART using the NXP MCUXpresso SDK.

.. note::
  This module will likely be superseded by a future ``pw_uart`` interface.

Setup
=====
This module requires a little setup:

1. Use ``pw_build_mcuxpresso`` to create a ``pw_source_set`` for an
   MCUXpresso SDK.
2. Include the debug console component in this SDK definition.
3. Specify the ``pw_third_party_mcuxpresso_SDK`` GN global variable to specify
   the name of this source set.
4. Use a target that calls ``pw_sys_io_mcuxpresso_Init`` in
   ``pw_boot_PreMainInit`` or similar.

The name of the SDK source set must be set in the
"pw_third_party_mcuxpresso_SDK" GN arg

Usage
=====
.. code-block:: cpp

  constexpr uint32_t kFlexcomm = 0;
  constexpr uint32_t kBaudRate = 115200;
  std::array<std::byte, 20> kBuffer = {};

  auto stream = UartStreamMcuxpresso{USART0,
                                     kBaudRate,
                                     kUSART_ParityDisabled,
                                     kUSART_OneStopBit,
                                     kBuffer};

  PW_TRY(stream.Init(CLOCK_GetFlexcommClkFreq(kFlexcomm)));

  std::array<std::byte, 10> to_write = {};
  PW_TRY(stream.Write(to_write));