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Module programming

A general tutorial common for all modules. For specific features and functions read module documentation.

Accessing specific module

Module API can be accessed by declaring its class. It will work right away, without a need for initialization. Multiple instances can be created.
If module is not physically connected, all functions calls will be ignored.

TotemModule11 module; // Declare use of distance sensor [11]
TotemModule11 module2(25151); // Declare use of distance sensor [11] with serial 25151
TotemModuleXX - each module hash class implementation name of TotemModule + number.
module - a variable name of TotemModule11. Can be any (sensor, controller, lineReader, ...). This instance is used to call module functions.
(25151) - if there are multiple modules with same number - serial is used to specify exact one. Using instance module2 will send commands to specific module only. Otherwise - all connected [11] modules will receive a command. Check Module scanner on how to get serial.

General functions

Each module library contains an API to access its functionality.

Communicating with module
// Read distance from sensor
int distance = module.getMM();
// Set RGB color to green
module.rgb.color(0, 255, 0);


TotemModule15 mod15;
TotemModule22 mod22;

void moduleEvt(int evt) {
  if (evt == TotemModule22::evtTemp) printf("Temp: %fC\n", mod22.getTempC());
  if (evt == TotemModule15::evtButtonA) printf("ButtonA: %d\n", mod15.getButtonA());
  if (evt == TotemModule15::evtButtonB) printf("ButtonB: %d\n", mod15.getButtonB());
  if (evt == TotemModule15::evtButtonC) printf("ButtonC: %d\n", mod15.getButtonC());
  if (evt == TotemModule15::evtKnobA) printf("KnobA: %d\n", mod15.getKnobA());
  if (evt == TotemModule15::evtKnobB) printf("KnobB: %d\n", mod15.getKnobB());
  if (evt == TotemModule15::evtKnobC) printf("KnobC: %d\n", mod15.getKnobC());

void setup() {
  // Call required functions once to receive
  // values and start broadcasting
void loop() {


Reading module functions like module.get() will always return cached value without blocking the code. This value is constantly updated in background with broadcast messages from module.
Code blocks shortly whem calling "get" function first time - to register an event and return value.

Using addEvent function is only useful if you need a callback when latest value update from module is received. Events are called only if value has changed compared to last one.


Register module event function. Will be called when new data is available.
Event data can be received simply by accessing module. Data is cached and won't initiate read request, but must be called inside registered function.
function - event function name (distanceEvent).

Multiple modules example

Simple code example to show usage of Line Follower + Potentiometer modules and interaction between them.
• Knob A - controls LED position on Line Follower
• Knob B - controls RGB color
• Knob C - controls RGB color

// Declare modules
TotemModule14 line; // Line follower module
TotemModule15 pot;  // Potentiometer module
// Start program
void setup() {
  // Empty
// Loop program
void loop() {
  // Read Potentiometer module knob positions
  int knobA = pot.getKnobA();
  int knobB = pot.getKnobB();
  int knobC = pot.getKnobC();
  // Display Knob A position on Line Follower module;
  line.led[map(knobA, 0, 255, 0, 7)].on(); // map [0:255] -> [0:7]
  // Change RoboBoard X4 RGB color depending on Knob B, C positions
    255-knobB, knobC, 255-knobC // red, green, blue
  // Delay 20 milliseconds

Module scanner

API to scan for TotemBUS modules. Can be used to get list of connected TotemBUS modules and their information (number and serial).

void setup() {
void loop() {
  // Try to find any module on the TotemBUS
  if (TotemX4Module::find()) {
    // Print found module
    Serial.printf("Found. Number: %d, Serial: %d\n", TotemX4Module::foundNumber, TotemX4Module::foundSerial);
  else {
    Serial.println("Not found");
  delay(1000); // Wait 1s

found TotemX4Module::find(number, serial)

Try to find module on TotemBUS network.
Available request types:
• all modules
• modules matching specified number
• module matching specified number and serial
Result can be acquired with TotemX4Module::foundNumber and TotemX4Module::foundSerial.
number - module number [0:255]. 0 - all modules
serial - module serial [0:32767]. 0 - ignore serial
Returns: found - true if module has been found

(number) TotemX4Module::foundNumber

Get found module number.

(serial) TotemX4Module::foundSerial

Get found module serial.