RAK13002 WisBlock IO Module Quick Start Guide

Prerequisite

What Do You Need?

Before going through each and every step on using the RAK13002 WisBlock module, make sure to prepare the necessary items listed below:

Hardware

Software

Download and install ArduinoIDE.
To add the RAKwireless Core boards on your Arduino Boards Manager, install the RAKwireless Arduino BSP.

Product Configuration

Hardware Setup

The RAK13002 WisBlock IO Module is designed as an IO extension module that allows you to connect external digital and analog modules to create a customized IoT solution. It supports two (2) I2C interfaces, two (2) UART interfaces, one (1) SPI Interface, six (6) GPIOs, and two (2) ADC interfaces. For more information about RAK13002, refer to the Datasheet.

The RAK13002 WisBlock IO Module can be mounted on the IO slot of the WisBlock Base board, as shown in Figure 1. Also, always secure the connection of the WisBlock module by using compatible screws.

Figure 3026: RAK13002 connection to WisBlock Base

Assembling and Disassembling of WisBlock Modules

Assembling

As shown in Figure 2, the location for the IO slot is properly marked by silkscreen. Follow carefully the procedure defined in RAK5005-O module assembly/disassembly instructions to attach a WisBlock module. Once attached, carefully fix the module with three pieces of M1.2 x 3 mm screws.

Figure 3027: RAK13002 assembly to WisBlock Base

Disassembling

The procedure in disassembling any type of WisBlock modules is the same.

First, remove the screws.

Figure 3028: Removing screws from the WisBlock module

Once the screws are removed, check the silkscreen of the module to find the correct location where force can be applied.

Figure 3029: Detaching silkscreen on the WisBlock module

Apply force to the module at the position of the connector, as shown in Figure 5, to detach the module from the baseboard.

Figure 3030: Applying even forces on the proper location of a WisBlock module

NOTE

If you will connect other modules to the remaining WisBlock Base slots, check on the WisBlock Pin Mapper tool for possible conflicts.

After all this setup, you can now connect the battery (optional) and USB cable to start programming your WisBlock Core.

Software Configuration and Example

The RAK13002 module exposes the IO pins, SPI, I2C, and UART communication ports. You can use these ports to connect sensors or modules, digital I/O, analog I/O, and slave devices. These ports are routed to the WisBlock Core through the IO connector.

For RAK13002, the accessible GPIO pin assignments are defined as follows in the Arduino IDE:

WB_IO1 for IO1, GPIO1 pin
WB_IO2 for IO2, GPIO2 pin
WB_IO3 for IO3, GPIO3 pin
WB_IO4 for IO4, GPIO4 pin
WB_IO5 for IO5, GPIO5 pin
WB_IO6 for IO6, GPIO6 pin
WB_SW1 for SW1 pin
WB_A0 for AIN0, ADC Input pin
WB_A1 for AIN1, ADC Input pin

Row/Column	Column 1	Column 2	Column 3	Column 4
Row 1	VCC	VCC	VCC	VCC
Row 2	GND	GND	GND	GND
Row 3	IO1	SCL1	TXD0	CS
Row 4	IO3	SDA1	RXD0	SDI
Row 5	IO4	SCL2	TXD1	SDO
Row 6	IO5	SDA2	RXD1	SCK
Row 7	IO6	LED1	AIN0	RST
Row 8	IO7	LED2	AIN1	SW1

I2C Connection on RAK13002

This is just an example and illustration on how to use the RAK13002 for external I2C sensors, modules, or devices. You can use any I2C device as long as it operates at 3.3 V.

Figure 3031: Connecting the RAK13002 to the I2C backpack of a 16x2 LCD

You need to select first the WisBlock Core you have, as shown in Figure 7 to Figure 9.

Figure 3032: Selecting RAK4631 as WisBlock Core

Figure 3033: Selecting RAK11200 as WisBlock Core

Figure 3034: Selecting RAK11300 as WisBlock Core

On the Arduino IDE, go to Sketch > Include Library > Manage Libraries. The Library Manager should open, then install the LiquidCrystal I2C library, as shown in Figure 10.

Figure 3035: Installing the LiquidCrystal I2C library

After successful installation of the library, you can now copy the following sample code into your Arduino IDE:

Click to view the code

#include LiquidCrystal_I2C.h

#include Wire.h

//initialize the liquid crystal library
//the first parameter is the I2C address
//the second parameter is how many rows are on your screen
//the third parameter is how many columns are on your screen
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  lcd.init();   //initialize lcd screen
  lcd.backlight(); // turn on the backlight
}
void loop() {

  start_display(); // star
  delay(1000); //wait for a second
  lcd.clear(); // clear the LCD content
  delay(1000); //wait for a second

}

void start_display(){

  lcd.setCursor(0,0); // tell the screen to write on the top row
  lcd.print("RAK13002");  // tell the screen to write “RAK13002” on the top row
  lcd.setCursor(0,1); // tell the screen to write on the bottom row
  lcd.print("EXAMPLE");  // tell the screen to write “EXAMPLE” on the bottom row

}

Then select the right Serial Port and upload the code, as shown in Figure 11 and Figure 12.

Figure 3036: Selecting the correct Serial Port

Figure 3037: Uploading the sample code

When you successfully uploaded the sample code, you will now be able to see the "RAK13002 EXAMPLE" in your LCD screen, as shown in Figure 13, which means that the module is properly communicating with the WisBlock core using the I2C protocol.

Figure 3038: RAK13002 EXAMPLE displayed on 16x2 LCD

If you are not seeing the same output, check the device's I2C address by using this code:

Click to view the code

/*
 * Scan the I2C Address of your LCD using
 * this example code. Make sure your SDA and SCL
 * line is connected properly.
 *
 * Follow the connection of LCD with I2C Backpack to RAK13002.
 */
#include <Wire.h> //include Wire.h library

void setup()
{
  Wire.begin(); // Wire communication begin
  Serial.begin(9600); // The baudrate of Serial monitor is set in 9600
  while (!Serial); // Waiting for Serial Monitor
  Serial.println("\nI2C Scanner");
}

void loop()
{
  byte error, address; //variable for error and I2C address
  int nDevices;

  Serial.println("Scanning...");

  nDevices = 0;
  for (address = 1; address < 127; address++ )
  {
    // The i2c_scanner uses the return value of
    // the Wire.endTransmission to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();

    if (error == 0)
    {
      Serial.print("I2C device found at address 0x");
      if (address < 16)
        Serial.print("0");
      Serial.print(address, HEX);
      Serial.println("  !");
      nDevices++;
    }
    else if (error == 4)
    {
      Serial.print("Unknown error at address 0x");
      if (address < 16)
        Serial.print("0");
      Serial.println(address, HEX);
    }
  }
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");

  delay(5000); // wait 5 seconds for the next I2C scan
}

Your device's I2C address should be displayed on the Serial Monitor, as shown in Figure 14.

Figure 3039: I2C address of your device

GPIO Connection on RAK13002

This is just an example and illustration on how to use the GPIO pins of RAK13002 for external sensors, modules, or devices. There are six (6) GPIO pins available on the RAK13002. You can use any of the GPIO pins as long as your modules, sensors, or devices operate at 3.3 V.

Figure 3040: Connecting Button as your GPIO component

You need to select first the WisBlock Core you have, as shown in Figure 16 to Figure 18.

Figure 3041: Selecting RAK4631 as WisBlock Core

Figure 3042: Selecting RAK11200 as WisBlock Core

Figure 3043: Selecting RAK11300 as WisBlock Core

Copy the following sample code into your Arduino IDE:

Click to view the code

/*
 * Reading Long Press and Short Press on a Button using RAK13002
 *
 */

// constants won't change. They're used here to set pin numbers:
const int BUTTON_PIN = WB_IO1; // the number of the pushbutton pin
const int SHORT_PRESS_TIME = 500; // 500 milliseconds

// Variables will change:
int lastState = LOW;  // the previous state from the input pin
int currentState;     // the current reading from the input pin
unsigned long pressedTime  = 0;
unsigned long releasedTime = 0;

void setup() {
  Serial.begin(9600);
  pinMode(BUTTON_PIN, INPUT_PULLUP);
}

void loop() {
  // read the state of the switch/button:
  currentState = digitalRead(BUTTON_PIN);

  if(lastState == HIGH && currentState == LOW)        // button is pressed
    pressedTime = millis();
  else if(lastState == LOW && currentState == HIGH) { // button is released
    releasedTime = millis();

    long pressDuration = releasedTime - pressedTime;

    if( pressDuration < SHORT_PRESS_TIME )
      Serial.println("A short press is detected");
  }

  // save the the last state
  lastState = currentState;
}

Then select the right Serial Port and upload the code, as shown in Figure 19 and Figure 20.

Figure 3044: Selecting the correct port

Figure 3045: Uploading your code

When you successfully uploaded the sample code, open the Serial Monitor of the Arduino IDE to see the button's reading logs. Try pressing the button, and if you see the logs, as shown in Figure 21, then your module or sensor is properly communicating to the WisBlock core using the Digital Interface.

Figure 3046: Serial Monitor Output

Analog Input (ADC) Connection on RAK13002

This is just an example and illustration on how to use the ADC pin of RAK13002 for external sensors, modules, or devices. There are two (2) ADC pins available on the RAK13002 that you can use as long as your modules, sensors, or devices operate at 3.3 V.

Figure 3047: Connecting the RAK13002 to the ADC pin of the sensor module

You need to select first the WisBlock Core you have, as shown in Figure 23 to Figure 25.

Figure 3048: Selecting RAK4631 as WisBlock Core

Figure 3049: Selecting RAK11200 as WisBlock Core

Figure 3050: Selecting RAK11300 as WisBlock Core

Copy the following sample code into your Arduino IDE:

Click to view the code

/*
* Reading ADC pin on RAK13002
* using Soil Moisture Sensor
*
*/

#define SS WB_A0 //Soil Moisture Sensor A0 to AIN0 of RAK13002

int sensor_value;

void setup() {
  Serial.begin(9600); // Setting up Serial Monitor to read in 9600 baudrate

}
void loop() {
  readSensor();
  delay(1000); //Read sensor value and print every 1 second.
}

void readSensor(){
  sensor_value = analogRead(SS);
  Serial.println(sensor_value);
}

Then select the right Serial Port and upload the code, as shown in Figure 26 and Figure 27.

Figure 3051: Selecting the correct Serial Port

Figure 3052: Uploading the sample code

When you successfully uploaded the sample code, open the Serial Monitor of the Arduino IDE to see the module's reading logs. If you see the logs, as shown in Figure 28, then your module or sensor is properly communicating to the WisBlock core using the Analog Interface.