Modem.js, GSM Modems on Node

Modem.js allows you to use your GSM modems on node. It offers a very simple API. It supports:

• Sending SMS messages
• Receiving SMS messages
• Getting delivery reports
• Deleting messages from memory
• Getting notifications when memory is full
• Getting signal quality
• Making ussd sessions
• 16bit (ucsd messages)
• 7bit (ascii) messages
• Multipart messages
• Getting notifications when someone calls

Installation

npm install modem

Instantiate

var modem = require('modem').Modem()

Open modem

modem.open(device, callback)

• device String Path to device, like /dev/ttyUSB0
  • callback Function called when modem is ready for further action

Send a message

modem.sms(message, callback)

• message Object
  • text String message body. Longs messages will be splitted and sent in multiple parts transparently.
  • receiver String receiver number.
  • encoding String. '16bit' or '7bit'. Use 7bit in case of English messages.

callback Fucntion(err, references) is called when sending is done.

• references Array contains reference ids for each part of sent message. (A message may take up to several parts)

Get delivery reports

modem.on('delivery', callback)

• callback Function is called with the following arguments:

• details Object detailed status report

  • smsc String Msisdn of SMS Sender
  • reference String Reference number of the delivered message
  • sender Msisdn of receiver
  • status Delivery status

• index String index of this delivery report in storage

Receive a message

modem.on('sms received', callback)

• callback Function will be called on each new message with following arguments:
• message Object
  • smsc String MSISDN of SMS Center
  • sender String MSISDN of sender
  • time Date Send time
  • text String message body

Get stored messages

modem.getMessages(callback)

• callback Function will be called with a single argument messages Array, which contains stores messages

Delete a message

modem.deleteMessage(message_index, callback)

• message_index Int is the message index to be deleted
• callback Function called when message is deleted

Get notified when memory is full

modem.on('memory full', callback)

• callback Function will be called when modem has no more space for further messages

Get notified when someone calls

modem.on('ring', callback)

• callback Function will be called on each RING with a single argument
• msisdn Number

Running custom AT commands

Modem.js allows you to run AT commands in a queue and manage them without messing the modem. API is still quite simple.

Run a command

job = modem.execute(at_command, [callback], [priority], [timeout])

• at_command String AT command you would like to execute
• callback Function called when execution is done, in form of (escape_char, [response])
  • escape_char String could be 'OK', 'ERROR' or '>'.
  • response String modem's response
• prior Boolean if set to true, command will be executed immediately
• timeout Integer timeout, in milliseconds, defaults to 60 seconds.
• job EventEmitter represents the added job.
  • it will emit timeout if executing job times out

USSD Sessions

Modem.js allows you to run ussd sessions.

Instantiate

var Session = require('modem').Ussd_Session

Create a session

var Session = require('modem').Ussd_Session
var CheckBalance = function(c) {
    var session = new Session;
    session.callback = c;

    session.parseResponse = function(response_code, message) {
        this.close();

        var match = message.match(/([0-9,\,]+)\sRial/);
        if(!match) {
            if(this.callback)
                this.callback(false);
            return ;
        }


        if(this.callback)
            this.callback(match[1]);

        session.modem.credit = match[1];
    }

    session.execute = function() {
        this.query('*141*#', session.parseResponse);
    }

    return session;
}