ESP-WROOM-32

Setup Your Environment

• Install the Arduino IDE (Integrated development environment). This is where You can download it for Mac OS X, Windows and Linux here.

Detailed instructions can be found below:

• Installing the Arduino IDE for Windows
• Installing the Arduino IDE for Mac
• Installing the Arduino IDE for Linux

New to the Arduino IDE?

If you are completely unfamiliar with the Arduino IDE, watch this video here to give you a better understanding of how it works.

To communicate with the Wemos board from your Arduino IDE, you must manually install ESP32 board definitions on your Arduino IDE, you can find the official tutorial for the different operating systems here

• Go to your Arduino IDE's installed directory
  • For Windows, it may be C:/Program Files (x86)/Arduino/hardware
  • For Mac, it may be /Applications/Arduino.app/Contents/Java/hardware
  • For Linux it may be ~/Arduino/hardware
• Make a folder called espressif. Inside it, create another folder called arduino-esp32.
• Download the zip file from here and copy the contents into the arduino-esp32 folder.
• To Install the board definitions for the ESP32, go inside arduino-esp32 folder:
• Go to folder esp and then tools folder
  • For Windows, run the get.exe
  • For Mac/Linux run python get.py in the terminal

Terminal tip

For Mac: To run python get.py in Mac, you need to open the Terminal app.

Type in cd then drag and drop the entire file containing the get.py file in it and drop it into your terminal - hit enter then type python get.py and hit enter.

For Linux, right click on the folder and select in Open in Terminal.

Folder Structure for Windows

Folder Structure for Mac

• Restart the Arduino IDE (Close and reopen again)

Selecting the board and port

The board has an On/Off Switch so make sure it's on before continuing any further

Once you've got it connected to your computer, get the name of your device's port using one of the following steps:

FTDI Drivers

FTDI Drivers allow for communication between your operating system and your deviceover USB. Installing them may require Administrative privilages.

Linux and Mac OS X

• Download and install the FTDI drivers from here. Select the appropriate version for your operating system and architecture.
• Open a terminal window and run the command `ls /dev/tty*
• Look for a device with the name that begins with /dev/tty e.g. /dev/tty.usbmodemPy343431 on MAC or /dev/ttyUSB0/dev/ttyACM0 on Linux.

Windows

• Download and install the FTDI drivers from here. Select the appropriate version for your operating system and architecture.
• Open the Windows start menu and search for Device Manager
• The COM port for the Pycom device will be listed as USB Serial Device or something similar
• Keep note of the COM port (e.g. COM4)

Install the required libraries

• In the Arduino IDE, Go to Sketch > Include Libraries > Manage Libraries

Install each of the following libraries by searching for their name in the search bar within the modal. A button will appear in the bottom right of the box that will allow you to install the library.

• WiFi
• ArduinoHttpClient
• ArduinoJson

Library Manager

Create the Sketch

• Click on File > New to create a new Sketch.
• Copy and paste the publish event example code below in place of the empty setup() and loop() functions

Arduino IDE new Sketch

• PublishEvent.ino

#include <ArduinoJson.h>

#include <WiFi.h>

#include <ArduinoHttpClient.h>

#include <Arduino.h>

const char* ssid = "your-ssid"; // Your WiFi ssid

const char* password = "your-password"; //Your Wifi password

// Get this sccret key from the wia dashboard. It should start with `d_sk`

const char* device_secret_key = "your-device-secret-key";

// Wia API parameters

char server[] = "api.wia.io";

char path[] = "/v1/events";

int port = 80;

WiFiClient client;

int status = WL_IDLE_STATUS;

StaticJsonBuffer<200> jsonBuffer;

HttpClient httpClient = HttpClient(client, server, port);

JsonObject& root = jsonBuffer.createObject();

void setup() {

// initialize serial communications and wait for port to open:

Serial.begin(115200);

while (!Serial) {

; // wait for serial port to connect. Needed for native USB port only

}

WiFi.begin(ssid, password);

Serial.print("Attempting to connect to SSID: ");

Serial.print(ssid);

// attempt to connect to WiFi network:

while (WiFi.status() != WL_CONNECTED) {

Serial.print(".");

// Connect to WPA/WPA2 network.

// wait 5 seconds for connection:

delay(5000);

}

Serial.print("IP address: ");

Serial.println(WiFi.localIP());

Serial.println("connecting...");

}

// Loop function runs continuously

void loop() {

root["name"] = "temperature";

root["data"] = 21.5;

// if you get a connection, report back via serial:

if (client.connect(server, port)) {

sendToWia(root);

} else {

// if you didn't get a connection to the server:

Serial.println("connection failed");

}

delay(3000); // Wait for 3 seconds to post again

}

// Adds the correct headers for HTTP and sends Data to Wia

void sendToWia(JsonObject& data) {

size_t len = data.measureLength();

size_t size = len + 1;

char json[size];

httpClient.beginRequest();

httpClient.post(path);

httpClient.sendHeader("Content-Type", "application/json");

httpClient.sendHeader("Content-Length", data.measureLength());

httpClient.sendHeader("Authorization", "Bearer " + String(device_secret_key));

httpClient.beginBody();

data.printTo(httpClient);

Serial.print("Posting ");

data.printTo(Serial);

Serial.println(" to Wia");

httpClient.endRequest();

}

Replace the following values of the following variables names (Place the correct value between the quotation marks right of the variable names in the code):

• ssid - with your WiFi network name.
• password - with your WiFi network password.
• device_secret_key with your device secret key from the Wia Dashboard (the one that begins with d_sk).

Selecting Board and Port in the Arduino IDE

• Select the Wemos Lollin 32 board type by going to Tools > Board
• Select the port that matches from above

Check that Upload Speed is set to 115200

Upload the code

• Go to Sketch > Upload to send it to your ESP-WROOM-32 .

Viewing your output

• Click on button on the right hand of the screen to view your Serial monitor (Denoted in image below)
• Make sure the baud rate is set to 1152000 (Shown in red rectangle in image below)

Publish an Event to Wia

If the Serial monitor doesn't show you connecting to a WiFi, You may need to push the RST(Reset) button to run the code on the board.

Now go to your device in the Wia dashboard and you should see the data appearing in the debugger.

Wia Device Debugger

Common errors

If you encounter an error like the one denoted in the image below, check if your board and port are correctly set in the Tools menu

Board or Port Failure