Project Description esp32_jsnsr04t_oled_mosfet_using_lib

This project uses the ESP-IDF components "mjd_jsnsr04t" and "mjd_ssd1306".

It demonstrates all the features of the JSN-SR04T V2.0 Waterproof Ultrasonic Sensor Module in combination with:

• An ESP32 development board.
• An OLED display module to show the measurements.
• A Power MOSFET to turn the sensor on and off (to save power consumption during deep sleep).
• A deep sleep cycle.
• It dumps the measurements in the debug log.

Goto the component directory "components/mjd_jsnsr04t" for documentation, installation, soldering instructions (if any), wiring instructions, data sheets, FAQ, photo's, etc.

What are the HW SW requirements of the ESP32 MJD Starter Kit?

Hardware

@tip The README of each ESP_IDF component contains a section "Shop Product".

• ESP development board. I suggest to buy a popular development board with good technical documentation and a significant user base. Examples: LOLIN D32, Adafruit HUZZAH32, LOLIN D32, Espressif ESP32-DevKitC, Pycom WiPy.
• JSN-SR04T-2.0 Waterproof Ultrasonic Sensor. Make sure to get the V2.0 which also works with 3.3V.
• OLED Display Module 0.91 Inch 128x32 Blue I2C SSD1306 DC 3.3V 5V.
• N Channel Power MOSFET that is 3.3V compatible. Good ones:

  • IRF3708 N-Channel Power MOSFET in package THT TO-220.

  • IRLML6244PBF N Channel MOSFET in package SMD SOT23-3 (can be soldered easily on a SOT23-3 breakout board).

Software: ESP-IDF v3.2

• A working installation of the Espressif ESP-IDF V3.2 development framework** (detailed instructions @ http://esp-idf.readthedocs.io/en/latest/get-started/index.html).

mkdir ~/esp
cd    ~/esp
git clone -b v3.2 --recursive https://github.com/espressif/esp-idf.git esp-idf-v3.2

• A C language editor or the Eclipse IDE CDT (instructions also @ http://esp-idf.readthedocs.io/en/latest/get-started/index.html).

Lab Setup / Wiring Diagram


PIN LAYOUT & WIRING

Sensor board    =>	ESP32 Development Board
--------------      -----------------------
1   5V              3.3V pin (not the 5V or VUSB pin!)
2   Trig            GPIO#16 (Adafruit Huzzah32 pin 16 @ bottomleft-2)
3	Echo            GPIO#14 (Adafruit Huzzah32 pin 14 @ bottomright-2)
4   GND             No connection here

OLED board  =>	ESP32 Development Board
----------      -----------------------
1   SDA            3.3V pin (not the 5V or VUSB pin!)
2   SCL            GPIO#17 (Adafruit Huzzah32 GPIO#17 = bottomleft-1)
3	VCC            GPIO#21 (Adafruit Huzzah32 GPIO#21 = bottomleft)
4   GND            No connection here

MOSFET             Destination
----------------   -----------------------
1   GATE           ESP32 dev board: GPIO#4 (Adafruit Huzzah32 GPIO#4 = bottomleft-6)
2   DRAIN          Sensor board: GND
2   DRAIN          OLED board: GND
3	SOURCE (GND)   ESP32 dev board: GND pin

Running the example

• Run make flash monitor to build and upload the example to your board and connect to its serial terminal.

Notes

• Change the logging level of each ESP32 project using make menuconfig from "INFO" to "DEBUG" if you want to get more details about the requests and responses that are exchanged using the UART data channel.

Reference: the ESP32 MJD Starter Kit SDK

Do you also want to create innovative IoT projects that use the ESP32 chip, or ESP32-based modules, of the popular company Espressif? Well, I did and still do. And I hope you do too.

The objective of this well documented Starter Kit is to accelerate the development of your IoT projects for ESP32 hardware using the ESP-IDF framework from Espressif and get inspired what kind of apps you can build for ESP32 using various hardware modules.

Go to https://github.com/pantaluna/esp32-mjd-starter-kit