ESP32-H2-DevKitM-1

ESP32-H2-DevKitM-1 is an entry-level development board based on Bluetooth® Low Energy and IEEE 802.15.4 combo module ESP32-H2-MINI-1 or ESP32-H2-MINI-1U. You can find the board schematic here.

Most of the I/O pins on the ESP32-H2-MINI-1/1U module are broken out to the pin headers on both sides of this board for easy interfacing. Developers can either connect peripherals with jumper wires or mount ESP32-H2-DevKitM-1 on a breadboard.

ESP32-H2-DevKitM-1 Board Layout

ESP32-H2-DevKitM-1 Board Layout

The block diagram below presents main components of the ESP32-H2-DevKitM-1.

ESP32-H2-DevKitM-1 Electrical Block Diagram

ESP32-H2-DevKitM-1 Electrical Block Diagram

Hardware Components

ESP32-H2-DevKitM-1 Hardware Components

ESP32-H2-DevKitM-1 Hardware Components

Buttons and LEDs

Board Buttons

There are two buttons labeled Boot and RST. The RST button is not available to software. It pulls the chip enable line that doubles as a reset line.

The BOOT button is connected to IO9. On reset it is used as a strapping pin to determine whether the chip boots normally or into the serial bootloader. After reset, however, the BOOT button can be used for software input.

Board LEDs

There is one on-board LED that indicates the presence of power. Another WS2812 LED is connected to GPIO8 and is available for software.

Current Measurement

The J5 headers on ESP32-H2-DevKitM-1 can be used for measuring the current drawn by the ESP32-H2-MINI-1/1U module:

  • Remove the jumper: Power supply between the module and peripherals on the board is cut off. To measure the module’s current, connect the board with an ammeter via J5 headers;

  • Apply the jumper (factory default): Restore the board’s normal functionality.

Note

When using 3V3 and GND pin headers to power the board, please remove the J5 jumper, and connect an ammeter in series to the external circuit to measure the module’s current.

Pin Mapping

ESP32-H2-DevKitM-1 pin layout

ESP32-H2-DevKitM-1 Pin Layout

Configurations

All of the configurations presented below can be tested by running the following commands:

$ ./tools/configure.sh esp32h2-devkit:<config_name>
$ make flash ESPTOOL_PORT=/dev/ttyUSB0 -j

Where <config_name> is the name of board configuration you want to use, i.e.: nsh, buttons, wifi… Then use a serial console terminal like picocom configured to 115200 8N1.

bmp180

This configuration enables the use of the BMP180 pressure sensor over I2C. You can check that the sensor is working by using the bmp180 application:

nsh> bmp180
Pressure value = 91531
Pressure value = 91526
Pressure value = 91525

coremark

This configuration sets the CoreMark benchmark up for running on the maximum number of cores for this system. It also enables some optimization flags and disables the NuttShell to get the best possible score.

Note

As the NSH is disabled, the application will start as soon as the system is turned on.

gpio

This is a test for the GPIO driver. It uses GPIO1 and GPIO2 as outputs and GPIO9 as an interrupt pin.

At the nsh, we can turn the outputs on and off with the following:

nsh> gpio -o 1 /dev/gpio0
nsh> gpio -o 1 /dev/gpio1

nsh> gpio -o 0 /dev/gpio0
nsh> gpio -o 0 /dev/gpio1

We can use the interrupt pin to send a signal when the interrupt fires:

nsh> gpio -w 14 /dev/gpio2

The pin is configured as a rising edge interrupt, so after issuing the above command, connect it to 3.3V.

i2c

This configuration can be used to scan and manipulate I2C devices. You can scan for all I2C devices using the following command:

nsh> i2c dev 0x00 0x7f

mcuboot_nsh

This configuration is the same as the nsh configuration, but it generates the application image in a format that can be used by MCUboot. It also makes the make bootloader command to build the MCUboot bootloader image using the Espressif HAL.

nsh

Basic configuration to run the NuttShell (nsh).

ostest

This is the NuttX test at apps/testing/ostest that is run against all new architecture ports to assure a correct implementation of the OS.

pwm

This configuration demonstrates the use of PWM through a LED connected to GPIO8. To test it, just execute the pwm application:

nsh> pwm
pwm_main: starting output with frequency: 10000 duty: 00008000
pwm_main: stopping output

rmt

This configuration configures the transmitter and the receiver of the Remote Control Transceiver (RMT) peripheral on the ESP32-H2 using GPIOs 8 and 2, respectively. The RMT peripheral is better explained here, in the ESP-IDF documentation. The minimal data unit in the frame is called the RMT symbol, which is represented by rmt_item32_t in the driver:

../../../../../_images/rmt_symbol3.png

The example rmtchar can be used to test the RMT peripheral. Connecting these pins externally to each other will make the transmitter send RMT items and demonstrates the usage of the RMT peripheral:

nsh> rmtchar

WS2812 addressable RGB LEDs

This same configuration enables the usage of the RMT peripheral and the example ws2812 to drive addressable RGB LEDs:

nsh> ws2812

Please note that this board contains an on-board WS2812 LED connected to GPIO8 and, by default, this config configures the RMT transmitter in the same pin.

rtc

This configuration demonstrates the use of the RTC driver through alarms. You can set an alarm, check its progress and receive a notification after it expires:

nsh> alarm 10
alarm_daemon started
alarm_daemon: Running
Opening /dev/rtc0
Alarm 0 set in 10 seconds
nsh> alarm -r
Opening /dev/rtc0
Alarm 0 is active with 10 seconds to expiration
nsh> alarm_daemon: alarm 0 received

spi

This configuration enables the support for the SPI driver. You can test it by connecting MOSI and MISO pins which are GPIO5 and GPIO0 by default to each other and running the spi example:

nsh> spi exch -b 2 "AB"
Sending:    AB
Received:   AB

If SPI peripherals are already in use you can also use bitbang driver which is a software implemented SPI peripheral by enabling CONFIG_ESPRESSIF_SPI_BITBANG option.

spiflash

This config tests the external SPI that comes with the ESP32-H2 module connected through SPI1.

By default a SmartFS file system is selected. Once booted you can use the following commands to mount the file system:

nsh> mksmartfs /dev/smart0
nsh> mount -t smartfs /dev/smart0 /mnt

timer

This config test the general use purpose timers. It includes the 4 timers, adds driver support, registers the timers as devices and includes the timer example.

To test it, just run the following:

nsh> timer -d /dev/timerx

Where x in the timer instance.

twai

This configuration enables the support for the TWAI (Two-Wire Automotive Interface) driver. You can test it by connecting TWAI RX and TWAI TX pins which are GPIO0 and GPIO2 by default to an external transceiver or connecting TWAI RX to TWAI TX pin by enabling the CONFIG_CAN_LOOPBACK option (Device Drivers -> CAN Driver Support -> CAN loopback mode) and running the can example:

nsh> can
nmsgs: 0
min ID: 1 max ID: 2047
Bit timing:
  Baud: 1000000
  TSEG1: 15
  TSEG2: 4
    SJW: 3
  ID:    1 DLC: 1

usbconsole

This configuration tests the built-in USB-to-serial converter found in ESP32-H2. esptool can be used to check the version of the chip and if this feature is supported. Running esptool.py -p <port> chip_id should have Chip is ESP32-H2 in its output. When connecting the board a new device should appear, a /dev/ttyACMX on Linux or a /dev/cu.usbmodemXXX om macOS. This can be used to flash and monitor the device with the usual commands:

make download ESPTOOL_PORT=/dev/ttyACM0
minicom -D /dev/ttyACM0

watchdog

This configuration tests the watchdog timers. It includes the 1 MWDTS, adds driver support, registers the WDTs as devices and includes the watchdog example application.

To test it, just run the following command:

nsh> wdog -i /dev/watchdogX

Where X is the watchdog instance.