How to Send/Receive SMS using AT commands?

RSK picture RSK · Jan 29, 2010 · Viewed 47.3k times · Source

Can anyone help me to send and receive SMS using AT commands in Python?

In case it matters, I'm using Fedora 8.

Which phone will be better with Linux (Nokia, Sony Ericson, Samsung,.....)? Will all phones support sending and receiving SMS using AT commands?

Answer

Stefano Palazzo picture Stefano Palazzo · Jul 28, 2011

Here's some example code that should get you started (in Python 3000):

import time
import serial

recipient = "+1234567890"
message = "Hello, World!"

phone = serial.Serial("/dev/ttyACM0",  460800, timeout=5)
try:
    time.sleep(0.5)
    phone.write(b'ATZ\r')
    time.sleep(0.5)
    phone.write(b'AT+CMGF=1\r')
    time.sleep(0.5)
    phone.write(b'AT+CMGS="' + recipient.encode() + b'"\r')
    time.sleep(0.5)
    phone.write(message.encode() + b"\r")
    time.sleep(0.5)
    phone.write(bytes([26]))
    time.sleep(0.5)
finally:
    phone.close()

You need to do two additional things:

  • Encode the message in the appropriate format (mostly GSM 03.38, there's a handy translation table at unicode.org). If you really don't care about any characters other than ASCII, you can just check if every character is in string.printable.

  • Check the length of the message (I'm not sure if it's to do with the encoding, but it's sometimes 140 characters, sometimes 160).

You can use phone.readall() to check for errors, but it's best to make sure your message is OK before you send it off to the phone. Note also that the sleeps seem to be necessary.

Most phones will understand this. In order to get my old Nokia C5 to open up the serial connection, I had to select "PC Suite" from the menu that pops up when you insert the USB cable. This should work equally well over Bluetooth.

The code uses the PySerial package, available for python 2 and 3.

See also: