The Espressif ESP-WROVER-KIT is a development board that uses the ESP32-WROVER module which includes a built-in 4 MByte SPI RAM. Most important features of the board are
Furthermore, many GPIOs are broken out for extension. The USB bridge based on FDI FT2232HL provides a JTAG interface for OCD debugging through the USB interface.
The following table shows the default board configuration sorted according to the defined functionality of GPIOs for different hardware options. This configuration can be overridden by \ref esp32_app_spec_conf "application-specific configurations".
- SPI_DEV(0) uses the HSPI interface with the GPIO2 pin as the MISO signal. Since GPIO2 has bootstrapping functionality, it might be necessary to to press the **Boot** button for flashing RIOT when the SD card or the peripheral hardware is attached to this SPI interface.
- GPIO0 cannot be used as SPI CS signal for external hardware connected to SPI_DEV(0). The reason for this is that the LEDs on this board are high-active and the default state of the LEDs after power-up causes a low level on the corresponding GPIO outputs.
- GPIO2 cannot be used as PWM_DEV(0) channel 1 / LED0 when SPI_DEV(0) is used in any way. Reason is that GPIO2 is the MISO signal when SPI_DEV(0) is used and is therefore an input. PWM channels are outputs.
- 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.
- GPIO16 and GPIO17 are used for the built-in SPI RAM and are not available on the I/O expansion connector, even though they are labeled there.
- GPIO32 and GPIO33 are attached to a 32 kHz crystal by default. To make them available as a GPIO on the I/O expansion connector, SMD resistors would need to be removed and soldered. Module `esp_rtc_timer_32k` is enabled by default.
MRF24J40-based IEEE 802.15.4 radio modules and ENC28J60-based Ethernet network interface modules have been tested with the board. You could use the following code in your \ref esp32_app_spec_conf "application-specific configuration" to use such modules:
```
#ifdef BOARD_ESP32_WROVER_KIT
#if MODULE_MRF24J40
#define MRF24J40_PARAM_CS GPIO9 /* MRF24J40 CS signal */
#define MRF24J40_PARAM_INT GPIO10 /* MRF24J40 INT signal */
#define MRF24J40_PARAM_RESET GPIO12 /* MRF24J40 RESET signal */
#endif
#if MODULE_ENC28J80
#define ENC28J80_PARAM_CS GPIO9 /* ENC28J80 CS signal */
#define ENC28J80_PARAM_INT GPIO10 /* ENC28J80 INT signal */
#define ENC28J80_PARAM_RESET GPIO12 /* ENC28J80 RESET signal */
For other parameters, the default values defined by the drivers can be used.
@note
- Only a few GPIOs are available for external hardware on ESP-WROVER-KIT boards. Therefore, MRF24J40 and ENC28J60 based modules use the same GPIOs and only one of these modules can be used simultaneously.
- The **RESET** signal of MRF24J40 and ENC28J60 based modules can also be connected to the **RST** pin of the board (see \ref esp32_wrover_kit_pinout "pinout") to keep the configured GPIO free for other purposes.
The following picture shows the pinout of the ESP-WROVER-KIT V3 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 \ref esp32_wrover_kit_table_board_configuration "optional functions" in table board configuration.
The corresponding board schematic can be found [here](https://dl.espressif.com/dl/schematics/ESP-WROVER-KIT_SCH-3.pdf).
\anchor esp32_wrover_kit_pinout
@image html "https://gitlab.com/gschorcht/RIOT.wiki-Images/raw/master/esp32/ESP-WROVER-KIT_V3_pinout.png?inline=false" "ESP32-WROVER-KIT V3 Pinout"
## <a name="flashing"> Flashing the Device </a> [[TOC](#toc)]
Flashing RIOT is quite straight forward. The board has a Micro-USB connector with reset/boot/flash logic. Just connect the board using the programming port to your host computer and type:
```
make flash BOARD=esp32-wrover-kit ...
```
The USB bridge is based on FDI FT2232HL and offers two USB interfaces:
- the first interface is the JTAG interface for [On-Chip debugging](#debugging)
- the second interface is the console interface, which is also used for flashing
Therefore, you have to declare the USB interface in the make command. For example, if the ESP32-WROVER-KIT is connected to the host computer through the USB interfaces `/dev/ttyUSB0` and `/dev/ttyUSB1`, the make command would be used as following:
Since the USB bridge based on FDI FT2232HL provides a JTAG interface for debugging through an USB interface, using ESP-ROVER-KIT is the easiest and most convenient way for On-Chip debugging. Please refer the [ESP-IDF Programming Guide](https://docs.espressif.com/projects/esp-idf/en/latest/api-guides/jtag-debugging/index.html) for details on how to setup and how to use ESP-WROVER-KIT and OpenOCD.
## <a name="other-resources"> Other Documentation Resources </a> [[TOC](#toc)]
There is a comprehensive [Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/get-started/get-started-wrover-kit-v3.html) for the ESP-WROVER-KIT with a lot information about hardware configuration.
