GET STARTED
=============

Installation
***************

Environment configuration and use based on Arduino IDE

Step 1. Click LIBRARY MANAGER in Arduino IDE


Step 2. Enter "arducam_mega" in the input box to search for the Arduacm_Mega library

Step 3. Click the INSTALL button and wait for the library to be installed successfully

.. image:: /_static/images/userGuide/download_library.png


.. note::
    This demo is based on the Arduino UNO development board

How it Works
***************

.. note::
    Arducam has released a full-featured script, which can be used to check all the functions of the Arducam Mega. Here we explain the specific workflow on Arduino UNO platform.


setup()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. code-block:: bash

    myUart.arducamUartBegin(921600);
    myCAM.begin();
    myCAM.registerCallBack(readBuffer,200);

Initialize serial communication
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Initialize serial communication, used for communication of Arducam Mega software.

Initialize the camera
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Use the begin() function to initialize the camera configuration.After this function runs, the camera will be configured as JPEG data format and the resolution will be the maximum.

- Function prototype:

.. code-block:: bash

    CamStatus begin(ArducamCamera* camera);



Register callback function
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Register the callback function. This function will be called in streaming mode.

- Function prototype:

.. code-block:: bash

    void registerCallback(ArducamCamera* camera, BUFFER_CALLBACK function, uint8_t blockSize);

.. warning::

    Transmission length should be less than 255



loop()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
In the loop, it follows the :ref:`specific protocol <From host to camera>` Arducam defined to parse  command sent by 
Arducam Mega host and do specific operation to response each command. 
The detail script is here:

Serial data receiving
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

    if (myUart.arducamUartAvailable())
    {
        temp = myUart.arducamUartRead();
        arducamDelayMs(5);
        if (temp == 0x55)
        {
            while (myUart.arducamUartAvailable())
            {
            commandBuff[commandLength] = myUart.arducamUartRead();
            if (commandBuff[commandLength] == 0xAA)
            { 
                break;
            }
            commandLength++;
            }    
            myUart.uartCommandProcessing(&(myCAM.cameraInfo),commandBuff,commandLength);
            commandLength = 0;
        }    
    }



Protocol analysis
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: bash

    uint8_t ArducamLink::uartCommandProcessing(Arducam* myCAM,uint8_t* commandBuff)
    {
        ArducamCamera* cameraInstance = myCAM->getCameraInstance();
        CamStatus state;
        uint16_t gainValue = 0;
        uint32_t exposureValue = 0;
        uint32_t exposureLen1 = 0;
        uint32_t exposureLen2 = 0;
        uint32_t exposureLen3 = 0;
        
        uint8_t cameraResolution = cameraInstance->currentPictureMode;
        uint8_t cameraFarmat = cameraInstance->currentPixelFormat; 
        switch (commandBuff[0])
        {
            case SET_PICTURE_RESOLUTION:																//Set Camera Resolution
                cameraResolution = commandBuff[1] & 0x0f;
                cameraFarmat = (commandBuff[1] & 0x70) >> 4;
                myCAM->takePicture((CAM_IMAGE_MODE)cameraResolution,(CAM_IMAGE_PIX_FMT)cameraFarmat);
                break;
            case SET_VIDEO_RESOLUTION:																//Set Video Resolution
                cameraResolution = commandBuff[1] & 0x0f;
                state = myCAM->startPreview((CAM_VIDEO_MODE)cameraResolution);
                if (state == CAM_ERR_NO_CALLBACK)
                {
                    Serial.println("callback function is not registered");
                }    
                break;
            case SET_BRIGHTNESS:																//Set brightness
                myCAM->setBrightness((CAM_BRIGHTNESS_LEVEL)commandBuff[1]);
                break;
            case SET_CONTRAST:																//Set Contrast
                myCAM->setContrast((CAM_CONTRAST_LEVEL)commandBuff[1]);
                break;
        ..............





flow chart
^^^^^^^^^^^^^

take pictures
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. image:: /_static/images/flowChart/takePicture.png

streaming mode
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. image:: /_static/images/flowChart/streamingMode.png