RIOT/boards/esp32-olimex-evb/doc.md

@defgroup boards_esp32_olimex-esp32-evb Olimex ESP32-EVB @ingroup boards_esp32 @brief Support for Olimex ESP32-EVB and ESP32-GATEWAY @author Gunar Schorcht gunar@schorcht.net

\section esp32_olimex-esp32-evb Olimex ESP32-EVB and ESP32-GATEWAY

Table of Contents

1. Overview
2. Hardware
   1. MCU
   2. Board Configuration
   3. Board Pinout
   4. Optional Hardware Configurations
3. Flashing the Device

Overview

Olimex ESP32-EVB and Olimex ESP32-GATEWAY are open source hardware boards which use the ESP32-WROOM module. The key features of the boards are:

• Ethernet LAN interface
• MicroSD card interface
• IR interface (Olimex ESP32-EVB only)
• CAN interface (Olimex ESP32-EVB only)
• two Relais (Olimex ESP32-EVB only)
• UEXT connector with I2C, SPI and UART interfaces (Olimex ESP32-EVB only)

Using the UEXT connector, a lot of off-board hardware modules can be connected to Olimex ESP32-EVB to extend the hardware without the need for soldering iron or breadboards.

Because of the differences in the on-board hardware, it is necessary to add the following line to the makefile of the application to use the according configuration for Olimex ESP32-GATEWAY:

USEMODULE += olimex_esp32_gateway

@image html "https://gitlab.com/gschorcht/RIOT.wiki-Images/raw/master/esp32/Olimex_ESP32-EVB_GATEWAY.png" "Olimex ESP32-EVB (left) and Olimex ESP32-GATEWAY (right)"

Back to table of contents

Hardware

This section describes

• the MCU,
• the default board configuration,
• optional hardware configurations,
• the board pinout.

Back to table of contents

MCU

Most features of the board are provided by the ESP32 SoC. For detailed information about the ESP32, see section \ref esp32_mcu_esp32 "MCU ESP32".

Back to table of contents

Board Configuration

Olimex ESP32-EVB and Olimex ESP32-GATEWAY have the following on-board components:

• Ethernet LAN interface
• MicroSD card interface
• IR interface (Olimex ESP32-EVB only)
• CAN interface (Olimex ESP32-EVB only)
• two Relais (Olimex ESP32-EVB only)
• UEXT connector with I2C, SPI and UART interfaces (Olimex ESP32-EVB only)

The following table shows the default board configuration, which is sorted according to the defined functionality of GPIOs. This configuration can be overridden by \ref esp32_application_specific_configurations "application-specific configurations".

Pin | Configuration\n ESP32-EVB | Configuration\n ESP32-GATEWAY | Remarks / Prerequisites | Configuration :------|:------------------|:-----------------|-|-| GPIO13 | I2C_DEV(0):SDA | SDMMC_DEV(0):DAT3 | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_i2c_interfaces "I2C Interfaces", \ref esp32_sdmmc_interfaces "SDMMC Interfaces" GPIO16 | I2C_DEV(0):SCL | I2C_DEV(0):SCL | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_i2c_interfaces "I2C Interfaces" GPIO14 | SPI_DEV(0):CLK, SDMMC_DEV(0):CLK | SDMMC_DEV(0):CLK | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_spi_interfaces "SPI Interfaces", \ref esp32_sdmmc_interfaces "SDMMC Interfaces" GPIO2 | SPI_DEV(0):MISO, SDMMC_DEV(0):DAT0 | SDMMC_DEV(0):DAT0 | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_spi_interfaces "SPI Interfaces", \ref esp32_sdmmc_interfaces "SDMMC Interfaces" GPIO15 | SPI_DEV(0):MOSI, SDMMC_DEV(0):CMD | SDMMC_DEV(0):CMD | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_spi_interfaces "SPI Interfaces", \ref esp32_sdmmc_interfaces "SDMMC Interfaces" GPIO17 | SPI_DEV(0):CS0 | I2C_DEV(0):SDA | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_spi_interfaces "SPI Interfaces" GPIO1 | UART_DEV(0):TxD | UART_DEV(0):TxD | Console (cannot be changed) | \ref esp32_uart_interfaces "UART interfaces" GPIO3 | UART_DEV(0):RxD | UART_DEV(0):RxD | Console (cannot be changed) | \ref esp32_uart_interfaces "UART interfaces" GPIO4 | UART_DEV(1):TxD | SDMMC_DEV(0):DAT1 | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_uart_interfaces "UART interfaces", \ref esp32_sdmmc_interfaces "SDMMC Interfaces" GPIO36 | UART_DEV(1):RxD | ADC_LINE(2) | on ESP32-EVB available at [UEXT1](https://www.olimex.com/Products/Modules/UEXT) | \ref esp32_uart_interfaces "UART interfaces" GPIO32 | Relais 1 | ADC_LINE(0) | | \ref esp32_adc_channels "ADC Channels" GPIO33 | Relais 2 | LED0 | | | GPIO34 | BUTTON0 | BUTTON0 | | | GPIO9 | PWM_DEV(0):0 | PWM_DEV(0):0 | | \ref esp32_pwm_channels "PWM Channels" GPIO10 | PWM_DEV(0):1 | PWM_DEV(0):1 | | \ref esp32_pwm_channels "PWM Channels" GPIO5 | CAN_DEV(0):TX | | | \ref esp32_can_interfaces "CAN Interfaces" GPIO35 | CAN_DEV(0):RX | ADC_LINE(1) | | \ref esp32_adc_channels "ADC Channels" GPIO12 | IR_DEV(0):TX | SDMMC_DEV(0):DAT2 | IR is not yet supported | \ref esp32_sdmmc_interfaces "SDMMC Interfaces" | GPIO39 | IR_DEV(0):RX | ADC_LINE(3) | IR is not yet supported | \ref esp32_adc_channels "ADC Channels" GPIO18 | EMAC_SMI:MDIO | EMAC_SMI:MDIO | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO23 | EMAC_SMI:MDC | EMAC_SMI:MDC | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO0 | EMAC_RMII:TX_CLK | EMAC_RMII:TX_CLK | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO21 | EMAC_RMII:TX_EN | EMAC_RMII:TX_EN | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO19 | EMAC_RMII:TXD0 | EMAC_RMII:TXD0 | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO22 | EMAC_RMII:TXD1 | EMAC_RMII:TXD1 | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO25 | EMAC_RMII:RXD0 | EMAC_RMII:RXD0 | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO26 | EMAC_RMII:RXD1 | EMAC_RMII:RXD1 | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" GPIO27 | EMAC_RMII:RX_DV | EMAC_RMII:RX_DV | LAN interface | \ref esp32_ethernet_network_interface "Ethernet MAC" \n

@note To use the board configuration for Olimex-ESP32-GATEWAY, it is necessary to add the following line to makefile of the application: \n

USEMODULE += olimex_esp32_gateway

• GPIO9 and GIOP10 can only be used in dout and dio \ref esp32_flash_modes "flash modes".
• It might be necessary to remove the SD card or the peripheral hardware attached to the SPI_DEV(0) interface for flashing RIOT. Reason is that the SPI_DEV(0) interface uses the HSPI interface with the GPIO2 pin as the MISO signal, which has bootstrapping functionality.

For detailed information about the configuration of ESP32 boards, see section \ref esp32_peripherals "Common Peripherals".

Back to table of contents

Optional Hardware Configurations

MRF24J40-based IEEE 802.15.4 radio modules have been tested with the board. You could use the following code in your \ref esp32_application_specific_configurations "application-specific configuration" to use such modules:

#ifdef BOARD_ESP32_OLIMEX_EVB && !MODULE_ESP32_OLIMEX_GATEWAY

#if MODULE_MRF24J40
#define MRF24J40_PARAM_CS       GPIO9       /* MRF24J40 CS signal    */
#define MRF24J40_PARAM_RESET    GPIO10      /* MRF24J40 RESET signal */
#define MRF24J40_PARAM_INT      GPIO34      /* MRF24J40 INT signal   */
#endif

#endif

For other parameters, the default values defined by the drivers can be used.

@note

• Since the Olimex-ESP32-GATEWAY does not break out the GPIO of the HSPI interface SPI_DEV(0), it is not possible to connect such module to Olimex-ESP32-GATEWAY.
• Since the Olimex-ESP32-EVB has a lot of on-board hardware, only a few GPIOs are available for external hardware.
• The RESET signal of MRF24J40 based modules can also be connected to the RST pin of the board (see \ref esp32_olimex_esp32_evb_pinout_img "pinout") to keep the configured GPIO free for other purposes.

Back to table of contents

Board Pinout

The following pictures shows the pinout of Olimex ESP32-EVB and Olimex ESP32-GATEWAY boards as defined by the default board configuration. The light green GPIOs are not used by configured on-board hardware components and can be used for any purpose. However, if optional off-board hardware modules are used, these GPIOs may also be occupied, see section \ref esp32_olimex_esp32_evb_board_configuration for more information.

The corresponding board schematics can be found on GitHub for Olimex ESP32-EVB board and for Olimex ESP32-GATEWAY.

\anchor esp32_olimex_esp32_evb_pinout_img @image html "https://gitlab.com/gschorcht/RIOT.wiki-Images/raw/master/esp32/Olimex_ESP32-EVB_pinout.png" "Olimex ESP32-EVB pinout" @image html "https://gitlab.com/gschorcht/RIOT.wiki-Images/raw/master/esp32/Olimex_ESP32-GATEWAY_pinout.png" "Olimex ESP32-GATEWAY pinout"

Back to table of contents

Flashing the Device

Flashing RIOT is quite easy. The board has a Micro-USB connector with reset/boot/flash logic. Just connect the board to your host computer and type using the programming port:

make flash BOARD=esp32-olimex-evb ...

For detailed information about ESP32 as well as configuring and compiling RIOT for ESP32 boards, see \ref esp32_riot.

Back to table of contents