Band Management

This example is part of the tools supplied to manage the GSM shield and shows how to use the GSM Library to manage the GSM band the modem connects to.

Check for general GSM band information. Typical regional configurations are:

  • Europe, Africa, Middle East: E-GSM(900)+DCS(1800)
  • USA, Canada, South America: GSM(850)+PCS(1900)
  • Mexico: PCS(1900)
  • Brazil: GSM(850)+E-GSM(900)+DCS(1800)+PCS(1900)

Hardware Required


image of the Arduino GSM Shield on top of an Arduino or Genuino board


 This sketch, for the Arduino GSM shield, checks the band  currently configured in the modem and allows you to change 

 Band Management

 This sketch, for the Arduino GSM shield, checks the band
 currently configured in the modem and allows you to change

 Please check
 Usual configurations:
 Europe, Africa, Middle East: E-GSM(900)+DCS(1800)
 USA, Canada, South America: GSM(850)+PCS(1900)
 Mexico: PCS(1900)
 Brazil: GSM(850)+E-GSM(900)+DCS(1800)+PCS(1900)

 * GSM shield

 created 12 June 2012
 by Javier Zorzano, Scott Fitzgerald

 This example is in the public domain.

// libraries
#include <GSM.h>

// initialize the library instance
GSMBand band;

void setup() {
  // initialize serial communications and wait for port to open:
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only

  // Beginning the band manager restarts the modem
  Serial.println("Restarting modem...");
  Serial.println("Modem restarted.");


void loop() {
  // Get current band
  String bandName = band.getBand(); // Get and print band name
  Serial.print("Current band:");
  Serial.println("Want to change the band you’re on?");
  String newBandName;
  newBandName = askUser();
  // Tell the user what we are about to do…
  Serial.print("\nConfiguring band ");
  // Change the band
  bool operationSuccess;
  operationSuccess = band.setBand(newBandName);
  // Tell the user if the operation was OK
  if (operationSuccess) {
  } else {
    Serial.println("Error while changing band");

  if (operationSuccess) {
    while (true);

// This function offers the user different options
// through the Serial interface
// The user selects one
String askUser() {
  String newBand;
  Serial.println("Select band:");
  // Print the different options
  Serial.println("1 : E-GSM(900)");
  Serial.println("2 : DCS(1800)");
  Serial.println("3 : PCS(1900)");
  Serial.println("4 : E-GSM(900)+DCS(1800) ex: Europe");
  Serial.println("5 : GSM(850)+PCS(1900) Ex: USA, South Am.");
  Serial.println("6 : GSM(850)+E-GSM(900)+DCS(1800)+PCS(1900)");

  // Empty the incoming buffer
  while (Serial.available()) {;

  // Wait for an answer, just look at the first character
  while (!Serial.available());
  char c =;
  if (c == '1') {
    newBand = GSM_MODE_EGSM;
  } else if (c == '2') {
    newBand = GSM_MODE_DCS;
  } else if (c == '3') {
    newBand = GSM_MODE_PCS;
  } else if (c == '4') {
    newBand = GSM_MODE_EGSM_DCS;
  } else if (c == '5') {
    newBand = GSM_MODE_GSM850_PCS;
  } else if (c == '6') {
    newBand = GSM_MODE_GSM850_EGSM_DCS_PCS;
  } else {
    newBand = "GSM_MODE_UNDEFINED";
  return newBand;

See Also:

Last revision 2018/08/23 by SM