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 (optional) String. '16bit' or '7bit'. Use 7bit in case of English messages. If encoding is not specified, the program will choose the best according to characters in text

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

USS Sessions

Modem.js allows you ro tun 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;
}