ESP-WROVER-KIT V4.1 Getting Started Guide
=========================================
:link_to_translation:`zh_CN:[中文]`

This user guide shows how to get started with the ESP-WROVER-KIT V4.1 development board including description of its functionality and configuration options. For descriptions of other versions of the ESP-WROVER-KIT check :doc:`../hw-reference/index`.

If you would like to start using this board right now, go directly to the :ref:`get-started-esp-wrover-kit-start-development` section.


What You Need
-------------

* 1 × :ref:`ESP-WROVER-KIT V4.1 board <get-started-esp-wrover-kit-v4.1-board-front>`
* 1 x Micro USB 2.0 Cable, Type A to Micro B
* 1 × PC loaded with Windows, Linux or Mac OS


Overview
--------

The ESP-WROVER-KIT is a development board built around the ESP32 and produced by `Espressif <https://espressif.com>`_. This board is compatible with multiple ESP32 modules, including the ESP32-WROOM-32, ESP32-WROVER and ESP32-WROVER-B. The ESP-WROVER-KIT features support for an LCD and a MicroSD card. The I/O pins have been broken out from the ESP32 module for easy extension. The board carries an advanced multi-protocol USB bridge (the FTDI FT2232HL), enabling developers to use JTAG directly to debug the ESP32 through the USB interface. The development board makes secondary development easy and cost-effective.


Functionality Overview
----------------------

The block diagram below illustrates the ESP-WROVER-KIT's main components and their interconnections.

.. figure:: ../../_static/esp-wrover-kit-block-diagram.png
    :align: center
    :alt: ESP-WROVER-KIT block diagram
    :figclass: align-center

    ESP-WROVER-KIT block diagram


Functional Description
----------------------

The following lists and figures describe the key components, interfaces, and controls of ESP-WROVER-KIT board.

32.768 kHz
    An external precision 32.768 kHz crystal oscillator provides a low-power consumption clock used during Deep-Sleep mode.
FT2232
    The FT2232 chip is a multi-protocol USB-to-serial bridge. Users can control and program the FT2232 chip through the USB interface to establish communication with ESP32. The FT2232 chip also features USB-to-JTAG interface. USB-to-JTAG is available on channel  A of the FT2232, whilst USB-to-serial is on channel B. The embedded FT2232 chip is one of the distinguishing features of the ESP-WROVER-KIT. It enhances users’ convenience in terms of application development and debugging. In addition, users need not purchase a JTAG debugger separately, which reduces the development cost, see `ESP-WROVER-KIT V4.1 schematic`_.
0R
    A zero Ohm resistor intended as a placeholder for a current shunt. May be desoldered or replaced with a current shunt to facilitate measurement of current required by ESP32 module depending on power mode.
ESP32-WROVER
    This version of ESP-WROVER-KIT board has ESP-WROVER-B module installed that integrates 64-Mbit PSRAM for flexible extended storage and data processing capabilities. The board can accommodate other versions of ESP modules described under :ref:`esp-wroom-solo-wrover-modules`.

    .. note::

        GPIO16 and GPIO17 are used as the CS and clock signal for PSRAM. To ensure reliable performance, the two GPIOs are not broken out.

Diagnostic LEDs
    Four red LEDs connected to GPIO pins of the FT2232 chip. Intended for future use.
UART
    Serial port: the serial TX/RX signals on the FT2232HL and the ESP32 are broken out to each side of JP2. By default, the two signals are connected with jumpers. To use the ESP32 module serial interface only, the jumpers may be removed and the module can be connected to another external serial device.
SPI
    SPI interface used by ESP32 to access flash and PSRAM memories inside the module. Please note that the voltage level on this interface depends on the module used.
CTS/RTS
    Serial port flow control signals: the pins are not connected to the circuitry by default. To enable them, respective pins of JP14 must be shorted with jumpers.
JTAG
    JTAG interface: the JTAG signals on FT2232HL and ESP32 are broken out to the two sides of JP2. By default, the two signals are disconnected. To enable JTAG, shorting jumpers are required on the signals as shown in section :ref:`get-started-esp-wrover-kit-setup-options`.
USB Port
    USB interface. It functions as the power supply for the board and the communication interface between PC and ESP32 module.
EN Button
    Reset button: pressing this button resets the system.
Boot Button
    Download button: holding down the **Boot** button and pressing the **EN** button initiates the firmware download mode. Then user can download firmware through the serial port.
Power Switch
    Power on/off button: toggling to the right powers the board on; toggling to the left powers the board off.
Power Selector
    Power supply selection interface: the ESP-WROVER-KIT can be powered through the USB interface or the 5V Input interface. The user can select the power supply with a jumper. More details can be found in section :ref:`get-started-esp-wrover-kit-setup-options`, jumper header JP7.
5V Input
    The 5V power supply interface is used as a backup power supply in case of full-load operation.
5V Power On LED
    This red LED indicates that a power supply (either from **USB** or **5V Input**) is applied to the board.
LDO
    NCP1117(1A). 5V-to-3.3V LDO. (There is an alternative pin-compatible LDO — LM317DCY, with an output current of up to 1.5A). NCP1117 can provide a maximum current of 1A. The LDO solutions are available with both fixed output voltage and variable output voltage. For details please refer to `ESP-WROVER-KIT V4.1 schematic`_.
Camera Connector
    Camera interface: a standard OV7670 camera module is supported.
RGB LED
    Red, green and blue (RGB) light emitting diodes (LEDs), which may be controlled by pulse width modulation (PWM).
I/O Connector
    All the pins on the ESP32 module are led out to the pin headers on the ESP-WROVER-KIT. Users can program ESP32 to enable multiple functions such as PWM, ADC, DAC, I2C, I2S, SPI, etc.
Micro SD Card Slot
    Develop applications that access Micro SD card for data storage and retrieval.
LCD
    ESP-WROVER-KIT supports mounting and interfacing a 3.2” SPI (standard 4-wire Serial Peripheral Interface) LCD, as shown on figure :ref:`get-started-esp-wrover-kit-v4.1-board-back`.

.. _get-started-esp-wrover-kit-v4.1-board-front:

.. figure:: ../../_static/esp-wrover-kit-v4.1-layout-front.png
    :align: center
    :alt: ESP-WROVER-KIT board layout - front
    :figclass: align-center

    ESP-WROVER-KIT board layout - front

.. _get-started-esp-wrover-kit-v4.1-board-back:

.. figure:: ../../_static/esp-wrover-kit-v4.1-layout-back.png
    :align: center
    :alt: ESP-WROVER-KIT board layout - back
    :figclass: align-center

    ESP-WROVER-KIT board layout - back


.. _get-started-esp-wrover-kit-setup-options:

Setup Options
-------------

There are three jumper headers available to set up the board functionality. Typical options to select from are listed in table below.

=======  ================  =========================================================
Header   Jumper Setting    Description of Functionality
=======  ================  =========================================================
JP7      |jp7-ext_5v|      Power ESP-WROVER-KIT board from an external power supply
JP7      |jp7-usb_5v|      Power ESP-WROVER-KIT board from an USB port
JP2      |jp2-jtag|        Enable JTAG functionality
JP2      |jp2-tx-rx|       Enable UART communication
JP14     |jp14|            Enable RTS/CTS flow control for serial communication
=======  ================  =========================================================


Allocation of ESP32 Pins
------------------------

Several pins / terminals of ESP32 module are allocated to the on board hardware. If certain hardware is not installed, e.g. nothing is plugged in to the Camera / JP4 header, then selected GPIOs may be used for other purposes.

Some of pins, like GPIO0 or GPIO2, have multiple functions and some of them are shared among on board and optional peripheral devices. Certain combinations of peripherals cannot work together. For example it is not possible to do JTAG debugging of an application that is using SD card, because several pins are shared by JTAG and the SD card slot.

In other cases peripherals can coexist under certain conditions. This is applicable to e.g. LCD screen and SD card that share only a single pin GPIO21. This pin is used to provide D/C (Data / Control) signal for the LCD and CD (Card Detect) signal read from the SD card slot. If the card detect functionality is not essential, then it may be disabled by removing R167, so both LCD and SD may operate together.

For more details what pins are shared among peripherals please refer to the table below.


Main I/O Connector / JP1
^^^^^^^^^^^^^^^^^^^^^^^^

The JP1 connector is shown in two columns in the middle under "I/O" headers. The two columns "Shared With" outside, describe where else on the board certain GPIO is used. 

=====================  =====  =====  =====================
Shared With            I/O    I/O    Shared With
=====================  =====  =====  =====================
                       3.3V   GND
NC/XTAL                IO32   IO33   NC/XTAL
JTAG, MicroSD          IO12   IO13   JTAG, MicroSD
JTAG, MicroSD          IO14   IO27   Camera
Camera                 IO26   IO25   Camera, LCD
Camera                 IO35   IO34   Camera
Camera                 IO39   IO36   Camera
JTAG                   EN     IO23   Camera, LCD
Camera, LCD            IO22   IO21   Camera, LCD, MicroSD
Camera, LCD            IO19   IO18   Camera, LCD
Camera, LCD            IO5    IO17   PSRAM
PSRAM                  IO16   IO4    LED, Camera, MicroSD
Camera, LED, Boot      IO0    IO2    LED, MicroSD
JTAG, MicroSD          IO15   5V
=====================  =====  =====  =====================

Legend:

* NC/XTAL - :ref:`32.768 kHz Oscillator <get-started-esp-wrover-kit-v4.1-xtal>`
* JTAG - :ref:`JTAG / JP8 <get-started-esp-wrover-kit-v4.1-jtag-header>`
* Boot - Boot button / SW2
* Camera - :ref:`Camera / JP4 <get-started-esp-wrover-kit-v4.1-camera-header>`
* LED - :ref:`RGB LED <get-started-esp-wrover-kit-v4.1-rgb-led-connections>`
* MicroSD - :ref:`MicroSD Card / J4 <get-started-esp-wrover-kit-v4.1-microsd-card-slot>`
* LCD - :ref:`LCD / U5 <get-started-esp-wrover-kit-v4.1-lcd-connector>`
* PSRAM - ESP32-WROVER's PSRAM, if ESP32-WROVER is installed


.. _get-started-esp-wrover-kit-v4.1-xtal:

32.768 kHz Oscillator
^^^^^^^^^^^^^^^^^^^^^

====  ==========
.     ESP32 Pin
====  ==========
1     GPIO32
2     GPIO33
====  ==========

.. note::

    As GPIO32 and GPIO33 are connected to the oscillator, they are not connected to JP1 I/O expansion connector to maintain signal integrity. This allocation may be changed from oscillator to JP1 by desoldering the 0R resistors from positions R11 / R23 and installing them in positions R12 / R24.


.. _get-started-esp-wrover-kit-v4.1-spi-flash-header:

SPI Flash / JP2
^^^^^^^^^^^^^^^

====  =============
.     ESP32 Pin
====  =============
1     CLK / GPIO6
2     SD0 / GPIO7
3     SD1 / GPIO8
4     SD2 / GPIO9
5     SD3 / GPIO10
6     CMD / GPIO11
====  =============

.. important::

    The module's flash bus is connected to the pin header JP2 through 0-Ohm resistors R140 ~ R145. If the flash frequency needs to operate at 80 MHz for reasons such as improving the integrity of bus signals, it is recommended that resistors R140 ~ R145 be desoldered. At this point, the module's flash bus is disconnected with the pin header JP2.


.. _get-started-esp-wrover-kit-v4.1-jtag-header:

JTAG / JP2
^^^^^^^^^^

====  ==============  =============
.     ESP32 Pin       JTAG Signal
====  ==============  =============
1     EN              TRST_N
2     MTMS / GPIO14   TMS
3     MTDO / GPIO15   TDO
4     MTDI / GPIO12   TDI
5     MTCK / GPIO13   TCK
====  ==============  =============


.. _get-started-esp-wrover-kit-v4.1-camera-header:

Camera / JP4
^^^^^^^^^^^^

====  ==========  =============================
.     ESP32 Pin   Camera Signal
====  ==========  =============================
 1    n/a         3.3V
 2    n/a         Ground
 3    GPIO27      SIO_C / SCCB Clock
 4    GPIO26      SIO_D / SCCB Data
 5    GPIO25      VSYNC / Vertical Sync
 6    GPIO23      HREF / Horizontal Reference
 7    GPIO22      PCLK / Pixel Clock
 8    GPIO21      XCLK / System Clock
 9    GPIO35      D7 / Pixel Data Bit 7
10    GPIO34      D6 / Pixel Data Bit 6
11    GPIO39      D5 / Pixel Data Bit 5
12    GPIO36      D4 / Pixel Data Bit 4
13    GPIO19      D3 / Pixel Data Bit 3
14    GPIO18      D2 / Pixel Data Bit 2
15    GPIO5       D1 / Pixel Data Bit 1
16    GPIO4       D0 / Pixel Data Bit 0
17    GPIO0       RESET / Camera Reset
18    n/a         PWDN / Camera Power Down
====  ==========  =============================

* Signals D0 .. D7 denote camera data bus


.. _get-started-esp-wrover-kit-v4.1-rgb-led-connections:

RGB LED
^^^^^^^

====  ==========  =========
.     ESP32 Pin   RGB LED 
====  ==========  =========
1     GPIO0       Red
2     GPIO2       Green
3     GPIO4       Blue
====  ==========  =========


.. _get-started-esp-wrover-kit-v4.1-microsd-card-slot:

MicroSD Card / J4
^^^^^^^^^^^^^^^^^

====  ==============  ===============
.     ESP32 Pin       MicroSD Signal
====  ==============  ===============
1     MTDI / GPIO12   DATA2
2     MTCK / GPIO13   CD / DATA3
3     MTDO / GPIO15   CMD
4     MTMS / GPIO14   CLK
5     GPIO2           DATA0
6     GPIO4           DATA1
7     GPIO21          CD
====  ==============  ===============


.. _get-started-esp-wrover-kit-v4.1-lcd-connector:

LCD / U5
^^^^^^^^

====  ==============  ===============
.     ESP32 Pin       LCD Signal
====  ==============  ===============
1     GPIO18          RESET
2     GPIO19          SCL
3     GPIO21          D/C
4     GPIO22          CS
5     GPIO23          SDA
6     GPIO25          SDO
7     GPIO5           Backlight
====  ==============  ===============


.. _get-started-esp-wrover-kit-start-development:

Start Application Development
-----------------------------

Before powering up the ESP-WROVER-KIT, please make sure that the board has been received in good condition with no obvious signs of damage.


Initial Setup
^^^^^^^^^^^^^

Select the source of power supply for the board by setting jumper JP7. The options are either **USB** port or an external **5V Input**. For this application, the selection of the ​USB port is sufficient. Enable UART communication by installing jumpers on JP2. Both selections are shown in table below. 

========================  ==========================
Power up from USB port    Enable UART communication
========================  ==========================
|jp7-usb_5v|              |jp2-tx-rx|
========================  ==========================

Do not install any other jumpers.

Turn the **Power Switch** on. The **5V Power On LED** should turn on.

Now to Development
^^^^^^^^^^^^^^^^^^

To start development of applications for ESP-WROVER-KIT, proceed to the :doc:`index` section which will walk you through the following steps:

* :ref:`get-started-setup-toolchain` in your PC to develop applications for ESP32 in C language
* :ref:`get-started-connect` the module to the PC and verify if it is accessible
* :ref:`get-started-build-flash` an example application to the ESP32
* :ref:`get-started-build-monitor` instantly what the application is doing


Related Documents
-----------------

* `ESP-WROVER-KIT V4.1 schematic`_ (PDF)
* `ESP32 Datasheet <https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf>`_ (PDF)
* `ESP32-WROVER-B Datasheet <https://espressif.com/sites/default/files/documentation/esp32-wrover-b_datasheet_en.pdf>`_ (PDF)
* :doc:`../api-guides/jtag-debugging/index`
* :doc:`../hw-reference/index`

.. |jp7-ext_5v| image:: ../../_static/esp-wrover-kit-v4.1-jp7-ext_5v.jpg
.. |jp7-usb_5v| image:: ../../_static/esp-wrover-kit-v4.1-jp7-usb_5v.jpg
.. |jp2-jtag| image:: ../../_static/esp-wrover-kit-v4.1-jp2-jtag.jpg
.. |jp2-tx-rx| image:: ../../_static/esp-wrover-kit-v4.1-jp2-tx-rx.jpg
.. |jp14| image:: ../../_static/esp-wrover-kit-v4.1-jp14.jpg

.. _ESP-WROVER-KIT V4.1 schematic: https://dl.espressif.com/dl/schematics/ESP-WROVER-KIT_V4_1.pdf

.. toctree::
    :hidden:

    get-started-wrover-kit-v3.rst
    get-started-wrover-kit-v2.rst
