APNHelperRK (community library)

Summary

Utilities for managing multiple 3rd-party SIM APNs from a single Electron binary

Example Build Testing

Library Read Me

This content is provided by the library maintainer and has not been validated or approved.

Dynamically setting the Electron APN

When you are using a third-party SIM card it's necessary to set the APN ("Access Point Name") for your cellular provider.

This is normally done in your code like this:

STARTUP(cellular_credentials_set("fast.tmobile.com", "", "", NULL));

However, it's also possible to set it dynamically, allowing for different SIMs with only a single firmware binary.

ICCID format

Fortunately, the ICCID is a formatted number that begins with the Issuer identification number:

Issuer identification number (IIN)

Maximum of seven digits:

Major industry identifier (MII), 2 fixed digits, 89 for telecommunication purposes. Country code, 1–3 digits, as defined by ITU-T recommendation E.164. Issuer identifier, 1–4 digits.

Particle SIM cards begin with 89340765. T-Mobile SIM cards in the US begin with 8901260, and so on. You can use this to determine which APN to use based on the SIM card that is inserted.

APNHelperRK

The APNHelperRK library is in the community libraries and also on Github.

The 1-simple-apn example should be straightforward to adapt to any application:

#include "Particle.h"
#include "APNHelperRK.h"

// SEMI_AUTOMATIC or MANUAL mode is required. This won't work using AUTOMATIC mode
SYSTEM_MODE(SEMI_AUTOMATIC);

// Note: Requires system firmware 0.6.0 or later!

// Optional: If you include this information will be printed to debugging serial
SerialLogHandler logHandler;

// Add APNs to this table
const APNHelperAPN apns[1] = {
// Always begins with 89, then country 01, provider 260 = T-Mobile
{ "8901260", "fast.t-mobile.com" }

// You don't need to specify the Particle SIM here. If there isn't otherwise a match, the
// code will just continue and use the default settings.
};
APNHelper apnHelper(apns, sizeof(apns) / sizeof(apns[0]));

void setup() {
Serial.begin(9600);

// Optional: If you don't do this the debugging print statements will probably output before you're
// able to attach the serial debugging terminal
// delay(8000);

// This must be done from setup, you can't do it from STARTUP.
apnHelper.setCredentials();

// You can't connect before you setCredentials. If the connection is lost in SEMI_AUTOMATIC mode it
// will be retried automatically.
Particle.connect();
}

void loop() {

}

Of particular note:

• You must use SYSTEM_MODE(SEMI_AUTOMATIC) or SYSTEM_MODE(MANUAL).
• System firmware 0.6.0 or later is required.
• You can include as many APNs in the table as you want (limited by flash size).
• Make sure you call apnHelper.setCredentials from setup(). It can't be called from STARTUP().
• Makes sure you call apnHelper.setCredentials before calling Particle.connect.

Browse Library Files