============= ESP32 DevKitC ============= The `ESP32 DevKitC `_ is a development board for the ESP32 SoC from Espressif, based on a ESP-WROOM-32 module. You can find the original V2 version and the newer V4 variant. They are pin compatible. .. list-table:: :align: center * - .. figure:: esp32-core-board-v2.jpg :align: center ESP32 DevKitC/Core V2 - .. figure:: esp32-devkitc-v4-front.jpg :align: center ESP32 DevKitC V4 Features ======== - ESP32 WROOM Module - USB-to-UART bridge via micro USB port - Power LED - EN and BOOT buttons (BOOT accessible to user) - SPI FLASH (size varies according to model Serial Console ============== UART0 is, by default, the serial console. It connects to the on-board CP2102 converter and is available on the USB connector USB CON8 (J1). It will show up as /dev/ttypUSB[n] where [n] will probably be 0 (is it 1 on my PC because I have a another device at ttyUSB0). Buttons and LEDs ================ Board Buttons ------------- There are two buttons labeled Boot and EN. The EN button is not available to software. It pulls the chip enable line that doubles as a reset line. The BOOT button is connected to IO0. 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 are several on-board LEDs for that indicate the presence of power and USB activity. None of these are available for use by software. Ethernet ======== ESP32 has a 802.11 hardware MAC, so just connects to external PHY chip. Due to the limited number of GPIOs in ESP32, it's recommended to use RMII to connect to an external PHY chip. Current driver also only supports RMII option. The RMII GPIO pins are fixed, but the SMI and functional GPIO pins are optional. RMII GPIO pins are as following: ========== ============= ESP32 GPIO PHY Chip GPIO ========== ============= IO25 RXD[0] IO26 RXD[1] IO27 CRS_DV IO0 REF_CLK IO19 TXD[0] IO21 TX_EN IO22 TXD[1] ========== ============= SMI GPIO pins (default option) are as following: ========== ============= ESP32 GPIO PHY Chip GPIO ========== ============= IO18 MDIO IO23 MDC ========== ============= Functional GPIO pins(default option) are as following: ========== ============= ESP32 GPIO PHY Chip GPIO ========== ============= IO5 Reset_N ========== ============= Espressif has an `official Ethernet development board `_. This driver has been tested according to this board and ESP32 core board + LAN8720 module. If users have some issue about using this driver, please refer the upper official document, specially the issue that GPIO0 causes failing to bring the ESP32 chip up. I2S === ESP32 has two I2S peripherals accessible using either the generic I2S audio driver or a specific audio codec driver (`CS4344 `__ bindings are available at the moment). The generic I2S audio driver enables using both the receiver module (RX) and the transmitter module (TX) without using any specific codec. Also, it's possible to use the I2S character device driver to bypass the audio subsystem and write directly to the I2S peripheral. .. note:: The I2S peripheral is able to work on two functional modes internally: 16 and 32-bit width. ESP32's I2S driver, however, uses an internal buffer to enable inserting padding bytes and provide the ability to play 8, 16, 24 or 32-bits/sample audio files. Sample rate and data width are automatically set by the upper half audio driver. .. note:: Also, it's possible to use 8, 16, 24, and 32-bit-widths writing directly to the I2S character device. Just make sure to set the bit-width:: $ make menuconfig -> System Type -> ESP32 Peripheral Selection -> I2S -> I2S0/1 -> Bit Witdh And make sure the data stream buffer being written to the I2S peripheral is aligned to the next boundary i.e. 16 bits for the 8 and 16-bit-widths and 32 bits for 24 and 32-bit-widths. The following configurations use the I2S peripheral:: * :ref:`platforms/xtensa/esp32/boards/esp32-devkitc/index:audio` * :ref:`platforms/xtensa/esp32/boards/esp32-devkitc/index:i2schar` * :ref:`platforms/xtensa/esp32/boards/esp32-devkitc/index:nxlooper` Pin Mapping =========== .. todo:: To be updated ===== ========== ========== Pin Signal Notes ===== ========== ========== ? ? ? ===== ========== ========== Configurations ============== All of the configurations presented below can be tested by running the following commands:: $ ./tools/configure.sh esp32-devkitc: $ make flash ESPTOOL_PORT=/dev/ttyUSB0 -j Where 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. audio ----- This configuration uses the I2S0 peripheral and an externally connected audio codec to play an audio file streamed over an HTTP connection while connected to a Wi-Fi network. **Audio Codec Setup** The CS4344 audio codec is connected on the following pins: ========== ========== ========================================= ESP32 Pin CS4344 Pin Description ========== ========== ========================================= 0 MCLK Master Clock 4 SCLK Serial Clock 5 LRCK Left Right Clock (Word Select) 18 SDIN Serial Data In on CS4344. (DOUT on ESP32) ========== ========== ========================================= **Simple HTTP server** Prepare a PCM-encoded (`.wav`) audio file with 16 or 24 bits/sample (sampled at 16~48kHz). This file must be placed into a folder in a computer that could be accessed on the same Wi-Fi network the ESP32 will be connecting to. Python provides a simple HTTP server. ``cd`` to the audio file folder on the PC and run:: $ python3 -m http.server Serving HTTP on 0.0.0.0 port 8000 (http://0.0.0.0:8000/) Look for your PC IP address and test playing the prepared audio on your browser: .. figure:: esp32-audio-config-file.png :align: center After successfully built and flashed, connect the board to the Wi-Fi network:: nsh> wapi psk wlan0 mypasswd 1 nsh> wapi essid wlan0 myssid 1 nsh> renew wlan0 Once connected, open NuttX's player and play the file according to its file name and the IP address of the HTTP server:: nsh> nxplayer nxplayer> play http://192.168.1.239:8000/tones.wav autopm ------ This configuration makes the device automatically enter the low power consumption mode when in the idle state, powering off the cpu and other peripherals. In minimum power save mode, the station wakes up every DTIM to receive a beacon. The broadcast data will not be lost because it is transmitted after DTIM. However, it can not save much more power if DTIM is short as the DTIM is determined by the access point. ble --- This configuration is used to enable Bluetooth Low Energy support for this board. You can scan for Bluetooth devices using the following commands:: NuttShell (NSH) NuttX-10.2.0 nsh> ifconfig bnep0 Link encap:UNSPEC at DOWN inet addr:0.0.0.0 DRaddr:0.0.0.0 Mask:0.0.0.0 wlan0 Link encap:Ethernet HWaddr ac:67:b2:53:8b:ec at UP inet addr:10.0.0.2 DRaddr:10.0.0.1 Mask:255.255.255.0 nsh> bt bnep0 scan start nsh> bt bnep0 scan stop nsh> bt bnep0 scan get Scan result: 1. addr: 63:14:2f:b9:9f:83 type: 1 rssi: -90 response type: 3 advertiser data: 1e ff 06 00 01 09 20 02 7c 33 a3 a7 cd c9 44 5b 2. addr: 52:ca:05:b5:ad:77 type: 1 rssi: -82 response type: 3 advertiser data: 1e ff 06 00 01 09 20 02 03 d1 21 57 bf 19 b3 7a 3. addr: 46:8e:b2:cd:94:27 type: 1 rssi: -92 response type: 2 advertiser data: 02 01 1a 09 ff c4 00 10 33 14 12 16 80 02 0a d4 4. addr: 46:8e:b2:cd:94:27 type: 1 rssi: -92 response type: 4 advertiser data: 18 09 5b 4c 47 5d 20 77 65 62 4f 53 20 54 56 20 5. addr: 63:14:2f:b9:9f:83 type: 1 rssi: -80 response type: 3 advertiser data: 1e ff 06 00 01 09 20 02 7c 33 a3 a7 cd c9 44 5b blewifi ------- Combines the capabilities of the ``ble`` and ``wifi`` configurations. ESP32 has only one 2.4 GHz ISM band RF module, which is shared by Bluetooth (BT & BLE) and Wi-Fi, so Bluetooth can't receive or transmit data while Wi-Fi is receiving or transmitting data and vice versa. Under such circumstances, ESP32 uses the time-division multiplexing method to receive and transmit packets. bmp280 ------ This configuration enables the use of the BMP280 temperature and pressure sensor over I2C. You can check that the sensor is working by using the ``sensortest`` application:: nsh> sensortest baro0 baro0: timestamp:66870000 value1:1008.37 value2:31.70 baro0: timestamp:66890000 value1:1008.31 value2:31.70 buttons ------- This configuration shows the use of the buttons subsystem. It can be used by executing the ``buttons`` application and pressing on any of the available board buttons:: nsh> buttons buttons_main: Starting the button_daemon buttons_main: button_daemon started button_daemon: Running button_daemon: Opening /dev/buttons button_daemon: Supported BUTTONs 0x01 nsh> Sample = 1 Sample = 0 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. cxx --- Development enviroment ready for C++ applications. You can check if the setup was successfull by running ``cxxtest``:: nsh> cxxtest Test ofstream ================================ printf: Starting test_ostream printf: Successfully opened /dev/console cout: Successfully opened /dev/console Writing this to /dev/console Test iostream ================================ Hello, this is only a test Print an int: 190 Print a char: d Test std::vector ============================= v1=1 2 3 Hello World Good Luck Test std::map ================================ Test C++17 features ========================== File /proc/meminfo exists! Invalid file! /invalid File /proc/version exists! efuse ----- A ``wifi`` configuration with the eFuse driver enabled. It can be accessed through the ``/dev/efuse`` device file. elf --- This configuration uses apps/examples/elf in order to test the ELF loader. It can be tested by executing the ``elf`` application. i2schar ------- This configuration enables the I2S character device and the i2schar example app, which provides an easy-to-use way of testing the I2S peripherals (I2S0 and I2S1), enabling both the TX and the RX for those peripherals. **I2S0 pinout** ========== ========== ========================================= ESP32 Pin Signal Pin Description ========== ========== ========================================= 0 MCLK Master Clock 4 BCLK Bit Clock (SCLK) 5 WS Word Select (LRCLK) 18 DOUT Data Out 19 DIN Data IN ========== ========== ========================================= **I2S1 pinout** ========== ========== ========================================= ESP32 Pin Signal Pin Description ========== ========== ========================================= 22 BCLK Bit Clock (SCLK) 23 WS Word Select (LRCLK) 25 DOUT Data Out 26 DIN Data IN ========== ========== ========================================= After successfully built and flashed, run on the boards's terminal:: i2schar -p /dev/i2schar[0-1] The corresponding output should show related debug informations. knsh ---- This is identical to the nsh configuration except that (1) NuttX is built as PROTECTED mode, monolithic module and the user applications are built separately and, as a consequence, (2) some features that are only available in the FLAT build are disabled. Protected Mode support for ESP32 relies on the PID Controller peripheral for implementing isolation between Kernel and Userspace. By working together with the MMU and Static MPUs of the ESP32, the PID Controller is able to restrict the application access to peripherals, on-chip memories (Internal ROM and Internal SRAM) and off-chip memories (External Flash and PSRAM). .. warning:: * The PID Controller driver is in **EXPERIMENTAL** state, so please consider the Protected Mode feature for ESP32 a **Proof-of-Concept**. * The PID Controller **does not** prevent the application from accessing CPU System Registers. leds ---- This configuration uses the on-board LED (or an external LED connected to GPIO2) to demonstrate the use of the userleds subsystem:: nsh> leds leds_main: Starting the led_daemon leds_main: led_daemon started led_daemon (pid# 3): Running led_daemon: Opening /dev/userleds led_daemon: Supported LEDs 0x01 led_daemon: LED set 0x01 led_daemon: LED set 0x00 led_daemon: LED set 0x01 led_daemon: LED set 0x00 led_daemon: LED set 0x01 max6675 ------- This configuration enables the use of the MAX6675 temperature sensor over SPI. The following pin configuration is used to connect the sensor: ===== ======= Pin Signal ===== ======= 15 CS 14 SCK 12 MISO ===== ======= You can check that the sensor is working by using the ``max6675`` application:: nsh> max6675 Unable to open file /dev/temp1 Unable to open file /dev/temp2 Unable to open file /dev/temp3 Starting... Channel SSP0/SPI1 Device 0: Temperature = 24! Channel SSP0/SPI1 Device 1: Not enabled! Channel SSP1/SPI2 Device 0: Not enabled! Channel SSP1/SPI2 Device 1: Not enabled! mcp2515 ------- This config is used to communicate with MCP2515 CAN over SPI chip. SPI3 is used and kept with the default IOMUX pins, i.e.: ===== ======= Pin Signal ===== ======= 5 CS 18 SCK 23 MOSI 19 MISO ===== ======= The MCP2515 interrupt (INT) pin is connected to the pin 22 of the ESP32-Devkit. mcuboot_slot_confirm -------------------- This configuration is used to represent an MCUboot update image that needs to be confirmed after flashing. The image can be confirmed by using the following command:: nsh> mcuboot_confirm Application Image successfully confirmed! For more information, check `this demo `_. mcuboot_update_agent -------------------- This configuration is used to represent an MCUboot image that contains an update agent to perform OTA updates. First, you will have to setup a HTTP server to provide the update image. To do that, we can run a simple Python server on the same folder that contains our binary file on the computer:: sudo python -m http.server 8080 After this, we can use NSH to connect to our network and use the agent to perform the firmware update:: nsh> ifup wlan0 nsh> wapi mode wlan0 2 nsh> wapi psk wlan0 mypasswd 3 nsh> wapi essid wlan0 myssid 1 nsh> renew wlan0 nsh> mcuboot_agent http://:8080/nuttx.bin For more information, check `this demo `_. modbus ------ This configurations shows how to use this device as a ModBus RTU Slave. After configuring the desired pins on menuconfig and wiring the RS485 converter, you can enable the ModBus to respond to queries:: nsh> modbus -e Now you will be able to read the ModBus registers using an application like ``mbpoll``. For more information, check `this video `_. module ------ This config is to run apps/examples/module. mqttc ----- This configuration tests the MQTT-C publisher example. From the host, start the broker and subscribe to the :code:`test` topic. Using ``mosquitto`` this should be:: $ mosquitto& $ mosquitto_sub -t test From the NSH, connect to an access point:: nsh> wapi psk wlan0 mypasswd 1 nsh> wapi essid wlan0 myssid 1 nsh> renew wlan0 Publish to the broker:: nsh> mqttc_pub -h 192.168.1.11 The default behavior is to publish the message :code:`test`. The following should be outputted:: nsh> mqttc_pub -h 192.168.1.11 Success: Connected to broker! Success: Published to broker! Disconnecting from 192.168.1.11 From the host the message :code:`test` should be outputted. ms5611 ------ This configuration enables the use of the MS5611 pressure sensor over I2C. You can check that the sensor is working by using the ``sensortest`` application:: nsh> sensortest baro0 baro0: timestamp:66870000 value1:1008.37 value2:31.70 baro0: timestamp:66890000 value1:1008.31 value2:31.70 nsh --- Basic NuttShell configuration (console enabled in UART0, exposed via USB connection by means of CP2102 converter, at 115200 bps). nxlooper -------- This configuration uses the I2S1 peripheral as an I2S receiver and the I2S0 peripheral as an I2S transmitter. The idea is to capture an I2S data frame using an I2S peripheral and reproduce the captured data on the other. **Receiving data on I2S1** The I2S1 will act as a receiver (master mode), capturing data from DIN, which needs to be connected to an external source as follows: ========== ========== ========================================= ESP32 Pin Signal Pin Description ========== ========== ========================================= 22 BCLK Bit Clock (SCLK) 23 WS Word Select (LRCLK) 26 DIN Data IN ========== ========== ========================================= **Transmitting data on I2S0** The I2S0 will act as a transmitter (master mode), replicating the data captured on I2S1. The pinout for the transmitter is as follows: ========== ========== ========================================= ESP32 Pin Signal Pin Description ========== ========== ========================================= 0 MCLK Master Clock 4 BCLK Bit Clock (SCLK) 5 WS Word Select (LRCLK) 18 DOUT Data Out ========== ========== ========================================= .. note:: The audio codec CS4344 can be connected to the transmitter pins to reproduce the captured data if the receiver's source is an audio data. **nxlooper** The ``nxlooper`` application captures data from the audio device with receiving capabilities (the I2S1 on this example) and forwards the audio data frame to the audio device with transmitting capabilities (the I2S0 on this example). After successfully built and flashed, run on the boards's terminal:: nsh> nxlooper nxlooper> loopback .. note:: ``loopback`` command default arguments for the channel configuration, the data width and the sample rate are, respectively, 2 channels, 16 bits/sample and 48KHz. These arguments can be supplied to select different audio formats, for instance:: nxlooper> loopback 2 8 44100 oneshot ------- This config demonstrate the use of oneshot timers present on the ESP32. To test it, just run the ``oneshot`` example:: nsh> oneshot Opening /dev/oneshot Maximum delay is 4294967295999999 Starting oneshot timer with delay 2000000 microseconds Waiting... Finished 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. The default version is for a single CPU but can be modified for an SMP test by adding:: CONFIG_SMP=y CONFIG_SMP_NCPUS=2 CONFIG_SPINLOCK=y pm -- This configuration enables the CPU power management through governors. psram ----- This config tests the PSRAM driver over SPIRAM interface. You can use the ramtest command to test the PSRAM memory. We are testing only 64KB on this example (64 * 1024), but you can change this number to 2MB or 4MB depending on PSRAM chip used on your board:: nsh> ramtest -w 0x3F800000 65536 RAMTest: Marching ones: 3f800000 65536 RAMTest: Marching zeroes: 3f800000 65536 RAMTest: Pattern test: 3f800000 65536 55555555 aaaaaaaa RAMTest: Pattern test: 3f800000 65536 66666666 99999999 RAMTest: Pattern test: 3f800000 65536 33333333 cccccccc RAMTest: Address-in-address test: 3f800000 65536 psram_usrheap ------------- This configuration works just like ``psram`` but allocating the user heap on the PSRAM. pwm --- This configuration demonstrates the use of PWM through a LED connected to GPIO12. To test it, just execute the ``pwm`` application:: nsh> pwm pwm_main: starting output with frequency: 10000 duty: 00008000 pwm_main: stopping output random ------ This configuration shows the use of the ESP32's True Random Number Generator with entropy sourced from Wi-Fi and Bluetooth noise. To test it, just run ``rand`` to get 32 randomly generated bytes:: nsh> rand Reading 8 random numbers Random values (0x3ffe0b00): 0000 98 b9 66 a2 a2 c0 a2 ae 09 70 93 d1 b5 91 86 c8 ..f......p...... 0010 8f 0e 0b 04 29 64 21 72 01 92 7c a2 27 60 6f 90 ....)d!r..|.'`o. 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 smp --- Another NSH configuration, similar to nsh, but also enables SMP operation. It differs from the nsh configuration only in these additional settings: SMP is enabled:: CONFIG_SMP=y CONFIG_SMP_NCPUS=2 CONFIG_SPINLOCK=y The apps/testing/smp test is included:: CONFIG_TESTING_SMP=y CONFIG_TESTING_SMP_NBARRIER_THREADS=8 CONFIG_TESTING_SMP_PRIORITY=100 CONFIG_TESTING_SMP_STACKSIZE=2048 sotest ------ This config is to run ``apps/examples/sotest``. spiflash -------- This config tests the external flash memory that comes with the ESP32 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 Note that mksmartfs is only needed the first time. sta_softap ---------- With this configuration you can run these commands to be able to connect your smartphone or laptop to your board:: nsh> ifup wlan1 nsh> dhcpd_start wlan1 nsh> wapi psk wlan1 mypasswd 3 nsh> wapi essid wlan1 nuttxap 1 In this case, you are creating the access point ``nuttxapp`` in your board and to connect to it on your smartphone you will be required to type the password ``mypasswd`` using WPA2. The ``dhcpd_start`` is necessary to let your board to associate an IP to your smartphone. tickless -------- This configuration enables the support for tickless scheduler mode. 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. wamr_wasi_debug --------------- This config is an example to use wasm-micro-runtime. It can run both of wasm bytecode and AoT compiled modules. This example uses littlefs on ESP32's SPI flash to store wasm modules. 1. Create a littlefs image which contains wasm modules. https://github.com/jrast/littlefs-python/blob/master/examples/mkfsimg.py is used in the following example:: % python3 mkfsimg.py \ --img-filename ..../littlefs.bin \ --img-size 3080192 \ --block-size 4096 \ --prog-size 256 \ --read-size 256 \ ..../wasm_binary_directory 2. Write the NuttX image and the filesystem to ESP32:: % esptool.py \ --chip esp32 \ --port /dev/tty.SLAB_USBtoUART \ --baud 921600 \ write_flash \ 0x1000 ..../bootloader-esp32.bin \ 0x8000 ..../partition-table-esp32.bin \ 0x10000 nuttx.bin \ 0x180000 ..../littlefs.bin 3. Mount the filesystem and run a wasm module on it:: nsh> mount -t littlefs /dev/esp32flash /mnt nsh> iwasm /mnt/.... wifi ---- Enables Wi-Fi support. You can define your credentials this way:: $ make menuconfig -> Application Configuration -> Network Utilities -> Network initialization (NETUTILS_NETINIT [=y]) -> WAPI Configuration Or if you don't want to keep it saved in the firmware you can do it at runtime:: nsh> wapi psk wlan0 mypasswd 3 nsh> wapi essid wlan0 myssid 1 nsh> renew wlan0 wifi_smp -------- This configuration is similar to ``wifi``. It also enables multiple cores on the CPU. watchdog -------- This config test the watchdog timers. It includes the 2 MWDTS, adds driver support, registers the WDTs as devices and includes the watchdog example. To test it, just run the following:: nsh> wdog -i /dev/watchdogx Where x is the watchdog instance. watcher ------- This configuration is an example of monitoring watchdog interrupts. To test it, enable the watcher daemon with ``watcher`` and monitor the tasks using ``watched``:: nsh> watcher Watcher Daemon has started! nsh> watched Starting watched tasks Creating Watched Task 1 - It will not feed the dog Creating Watched Task 2 - It will feed the dog Creating Watched Task 3 - It will feed the dog Creating Watched Task 4 - It will not feed the dog nsh> *** Printing Tasks Status *** Watched Task 1 starved the dog. Watched Task 2 fed the dog. Watched Task 3 fed the dog. Watched Task 4 fed the dog. *** Printing Tasks Status *** Watched Task 1 starved the dog. Watched Task 2 fed the dog. Watched Task 3 fed the dog. Watched Task 4 starved the dog. wifinsh ------- The ``wifinsh`` is similar to the ``wifi`` board example, but it will connect automatically to your Access Point (Wi-Fi Router) and will run telnet daemon in the board. Then you can connect to your board from your computer using the telnet program. After configuring the ``esp32-devkit:wifinsh`` you need to define your creden- tials in the menuconfig. You can define your credentials this way:: $ make menuconfig -> Application Configuration -> Network Utilities -> Network initialization (NETUTILS_NETINIT [=y]) -> WAPI Configuration Find your board IP using ``nsh> ifconfig`` and then from your computer:: $ telnet 192.168.x.y Where x and y are the last two numbers of the IP that your router gave to your board. Debugging with OpenOCD ====================== Akizukidenshi FT232HL --------------------- Akizukidenshi's FT232HL, a FT232H based JTAG adapter (http://akizukidenshi.com/catalog/g/gK-06503/) with JP3 and JP4 closed, and connected to ESP32 as: +------------------+-------------+ | ESP32-DevKitC V4 | FT232HL | +=======+==========+=============+ | J2 | J3 | J2 | +-------+----------+-------------+ | IO13 | | AD0 (TCK) | +-------+----------+-------------+ | IO12 | | AD1 (TDI) | +-------+----------+-------------+ | | IO15 | AD2 (TDO) | +-------+----------+-------------+ | IO14 | | AD3 (TMS) | +-------+----------+-------------+ | GND | | GND | +-------+----------+-------------+ can be used with ESP-IDF version of openocd with:: % openocd -f board/esp32-wrover-kit-1.8v.cfg