ESP-WROVER-KIT V3 Getting Started Guide

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This guide shows how to get started with the ESP-WROVER-KIT V3 development board and also provides information about its functionality and configuration options. For the description of other ESP-WROVER-KIT versions, please check ESP32 Hardware Reference.

What You Need

You can skip the introduction sections and go directly to Section Start Application Development.

Overview

ESP-WROVER-KIT is an ESP32-based development board produced by Espressif. This board features an integrated LCD screen and MicroSD card slot.

ESP-WROVER-KIT comes with the following ESP32 modules:

Its another distinguishing feature is the embedded FTDI FT2232HL chip - an advanced multi-interface USB bridge. This chip enables to use JTAG for direct debugging of ESP32 through the USB interface without a separate JTAG debugger. ESP-WROVER-KIT makes development convenient, easy, and cost-effective.

Most of the ESP32 I/O pins are broken out to the board’s pin headers for easy access.

Note

The version with the ESP32-WROVER module uses ESP32’s GPIO16 and GPIO17 as chip select and clock signals for PSRAM. By default, the two GPIOs are not broken out to the board’s pin headers in order to ensure reliable performance.

Functionality Overview

The block diagram below shows the main components of ESP-WROVER-KIT and their interconnections.

ESP-WROVER-KIT block diagram

ESP-WROVER-KIT block diagram

Functional Description

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

ESP-WROVER-KIT board layout - front

ESP-WROVER-KIT board layout - front

ESP-WROVER-KIT board layout - back

ESP-WROVER-KIT board layout - back

The table below provides description in the following manner:

  • Starting from the first picture’s top right corner and going clockwise

  • Then moving on to the second picture

Key Component

Description

32.768 kHz

External precision 32.768 kHz crystal oscillator serves as a clock with low-power consumption while the chip is in Deep-sleep mode.

0R

Zero-ohm resistor intended as a placeholder for a current shunt, can be desoldered or replaced with a current shunt to facilitate the measurement of ESP32’s current consumption in different modes.

ESP32 Module

Either ESP32-WROOM-32 or ESP32-WROVER with an integrated ESP32. The ESP32-WROVER module features all the functions of ESP32-WROOM-32 and integrates an external 32-MBit PSRAM for flexible extended storage and data processing capabilities.

FT2232

The FT2232 chip serves as a multi-protocol USB-to-serial bridge which can be programmed and controlled via USB to provide communication with ESP32. FT2232 also features USB-to-JTAG interface which is available on channel A of the chip, while USB-to-serial is on channel B. The FT2232 chip enhances user-friendliness in terms of application development and debugging. See ESP-WROVER-KIT V3 schematic.

UART

Serial port. The serial TX/RX signals of FT2232 and ESP32 are broken out to the inward and outward sides of JP11 respectively. By default, these pairs of pins are connected with jumpers. To use ESP32’s serial interface, remove the jumpers and connect another external serial device to the respective pins.

SPI

By default, ESP32 uses its SPI interface to access flash and PSRAM memory inside the module. Use these pins to connect ESP32 to another SPI device. In this case, an extra chip select (CS) signal is needed. Please note that the interface voltage for the version with ESP32-WROVER is 1.8V, while that for the version with ESP32-WROOM-32 is 3.3V.

CTS/RTS

Serial port flow control signals: the pins are not connected to the circuitry by default. To enable them, short the respective pins of JP14 with jumpers.

JTAG

JTAG interface. JTAG signals of FT2232 and ESP32 are broken out to the inward and outward sides of JP8 respectively. By default, these pairs of pins are disconnected. To enable JTAG, short the respective pins with jumpers as shown in Section Setup Options.

EN

Reset button.

Boot

Download button. Holding down Boot and then pressing EN initiates Firmware Download mode for downloading firmware through the serial port.

USB

USB interface. Power supply for the board as well as the communication interface between a computer and the board.

Power Key

Power On/Off Switch. Toggling toward USB powers the board on, toggling away from USB powers the board off.

Power Select

Power supply selector interface. The board can be powered either via USB or via the 5V Input interface. Select the power source with a jumper. For more details, see Section Setup Options, jumper header JP7.

5V Input

The 5V power supply interface can be more convenient when the board is operating autonomously (not connected to a computer).

LDO

NCP1117(1A). 5V-to-3.3V LDO. NCP1117 can provide a maximum current of 1A. The LDO on the board has a fixed output voltage. Although, the user can install an LDO with adjustable output voltage. For details, please refer to ESP-WROVER-KIT V3 schematic.

Camera

Camera interface, a standard OV7670 camera module.

RGB LED

Red, green and blue (RGB) light emitting diodes (LEDs), can be controlled by pulse width modulation (PWM).

I/O

All the pins on the ESP32 module are broken out to pin headers. You can program ESP32 to enable multiple functions, such as PWM, ADC, DAC, I2C, I2S, SPI, etc.

MicroSD Card Slot

Useful for developing applications that access MicroSD card for data storage and retrieval.

LCD

Support for mounting and interfacing a 3.2” SPI (standard 4-wire Serial Peripheral Interface) LCD, as shown on figure ESP-WROVER-KIT board layout - back.

Setup Options

There are five jumper blocks available to set up the board functionality. The most frequently required options are listed in the table below.

Header

Jumper Setting

Description of Functionality

JP7

jp7-ext_5v

Power ESP-WROVER-KIT via an external power supply

JP7

jp7-usb_5v

Power ESP-WROVER-KIT via USB

JP8

jp8

Enable JTAG functionality

JP11

jp11-tx-rx

Enable UART communication

JP14

jp14

Enable RTS/CTS flow control for serial communication

Allocation of ESP32 Pins

Some pins / terminals of ESP32 are allocated for use with the onboard or external hardware. If that hardware is not used, e.g., nothing is plugged into the Camera (JP4) header, then these GPIOs can be used for other purposes.

Some of the pins, such as GPIO0 or GPIO2, have multiple functions and some of them are shared among onboard and external 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, for example, 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 as well as the 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 on which pins are shared among which peripherals, please refer to the table in the next section.

Main I/O Connector / JP1

The JP1 connector consists of 14x2 male pins whose functions are shown in the middle two “I/O” columns of the table below. The two “Shared With” columns on both sides describe where else on the board a certain GPIO is used.

Shared With

I/O

I/O

Shared With

n/a

3.3V

GND

n/a

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:

32.768 kHz Oscillator

.

ESP32 Pin

1

GPIO32

2

GPIO33

Note

Since GPIO32 and GPIO33 are connected to the oscillator by default, they are not connected to the JP1 I/O connector to maintain signal integrity. This allocation may be changed from the oscillator to JP1 by desoldering the zero-ohm resistors from positions R11 / R23 and re-soldering them to positions R12 / R24.

SPI Flash / JP13

.

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 jumper block JP13 through zero-ohm resistors R140 ~ R145. If the flash memory needs to operate at the frequency of 80 MHz, for reasons such as improving the integrity of bus signals, you can desolder these resistors to disconnect the module’s flash bus from the pin header JP13.

JTAG / JP8

.

ESP32 Pin

JTAG Signal

1

EN

TRST_N

2

MTMS / GPIO14

TMS

3

MTDO / GPIO15

TDO

4

MTDI / GPIO12

TDI

5

MTCK / GPIO13

TCK

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

RGB LED

.

ESP32 Pin

RGB LED

1

GPIO0

Red

2

GPIO2

Green

3

GPIO4

Blue

MicroSD Card

.

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

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

Start Application Development

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

Initial Setup

Please set only the following jumpers shown in the pictures below:

  • Select USB as the power source using the jumper block JP7.

  • Enable UART communication using the jumper block JP11.

Power up from USB port

Enable UART communication

jp7-usb_5v

jp11-tx-rx

Do not install any other jumpers.

Turn the Power Switch to ON, the 5V Power On LED should light up.

Now to Development

Please proceed to ESP32 Hardware Reference, where Section Installation Step by Step will quickly help you set up the development environment and then flash an example project onto your board.

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