Wemos LOLIN D32 Pro + SHT30 macOS Setup

D32 Setup.mdown

To get USB access:

• install the USB serial driver, check that you see a /dev/cu.wchusbserial1410 device when plugging in the board over USB

To deploy MicroPython on the board:

• get the MicroPython firmware (get the SPIRAM variant to get access to the 4MB of RAM)
• install esptool by running sudo pip install esptool
• clear the flash by running esptool.py --chip esp32 --port /dev/cu.usbserial-1410 erase_flash
• flash MicroPython by running esptool.py --chip esp32 --port /dev/cu.usbserial-1410 --baud 460800 write_flash -z 0x1000 esp32spiram-idf3-20190125-v1.10.bin
• access MicroPython by running screen /dev/cu.usbserial-1410 115200
• exit screen through CTRL + a then k

To setup a WiFi connection from the MicroPython prompt:

import network
wifi = network.WLAN(network.STA_IF)
wifi.active(True)
wifi.config(dhcp_hostname="Sensor")
wifi.connect("WIFI_NETWORK", "WIFI_PASSWORD")

To read the temperature from the SHT30 sensor board from the MicroPython prompt:

import machine
i2c = machine.I2C(scl=machine.Pin(22), sda=machine.Pin(21))
address = i2c.scan()[0]
i2c.writeto(address, b'\x2C\x10')
data = i2c.readfrom(address, 6)
temperature = (((data[0] << 8 |  data[1]) * 175) / 0xFFFF) - 45
humidity = (((data[3] << 8 | data[4]) * 100.0) / 0xFFFF)
print("%.1f degrees, %.1f%% humidity" % (temperature, humidity))

See the reference SHT30 code for more info.

To deploy Arduino on the board:

• download the Arduino IDE
• right click on the app and select Open to bypass the app codesigning issues
• after Arduino starts, open the Preferences window
• in the Additional Board Manager URLs box, enter: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
• go to the Tools > Board > Board Manager menu, search for ESP32 and install that package
• select LOLIN D32 PRO as your board and /dev/cu.usbserial-1410 as your serial port
• click the arrow button to deploy your code to the board

To install esp-idf and use their serial logger:

• run git clone --recursive https://github.com/espressif/esp-idf.git
• install esp-idf through cd esp-idf ; ./install.sh
• set the right environment variables through . ./export.sh
• now you can run idf.py monitor