25.2. Syntax of the +CMGS AT Command in SMS Text Mode

In SMS text mode, the syntax of the +CMGS AT command is: (Optional parameters are enclosed in square brackets.)

+CMGS=address[,address_type]<CR>sms_message_body<Ctrl+z>

Before we discuss each of the parameters, let's see an example that gives you some idea of how an actual command line should look like:

AT+CMGS="+85291234567",145<CR>This is an example for illustrating the syntax of the +CMGS AT command in SMS text mode.<Ctrl+z>

The address Parameter

The first parameter of the +CMGS AT command, address, specifies the destination address to send the SMS message to. Usually it is a mobile number formatted using the typical ISDN / telephony numbering plan (ITU E.164/E.163). For example, "+85291234567", "91234567", etc. Note that the value passed to the address parameter should be a string, i.e. it should be enclosed in double quotes.

The address_type Parameter

The second parameter of the +CMGS AT command, address_type, specifies the type of the address assigned to the address parameter. Two values are commonly used. They are 129 and 145:

• 129. It means the value of address is formatted using the typical ISDN / telephony numbering plan (ITU E.164/E.163) but it is not sure whether the value of address is an international number, a national number or a number of other types. Example addresses: "85291234567", "91234567".

• 145. It means the value of address is formatted using the typical ISDN / telephony numbering plan (ITU E.164/E.163) and it is an international number. Example address: "+85291234567".

As address_type is an optional parameter, it can be omitted. If you do so, the GSM/GPRS modem or mobile phone will use the default value of the address_type parameter, which is:

• 129 if the value of address does not start with a "+" character. For example, "85291234567".

• 145 if the value of address starts with a "+" character. For example, "+85291234567".

The <CR> Character

<CR>, which represents the carriage return character, follows the address_type parameter. When the GSM/GPRS modem or mobile phone receives the carriage return character, it will send back a prompt formed by these four characters: the carriage return character, the linefeed character, the ">" character and the space character. If you don't understand what this means, don't worry. This should be clear to you when you see the example in the section "Example Demonstrating How to Use the +CMGS AT Command to Send SMS Text Messages in SMS Text Mode".

The sms_message_body Parameter

The third parameter of the +CMGS AT command, sms_message_body, specifies the body of the SMS message to be sent. Entering the <Esc> character will cancel the +CMGS AT command. If you don't understand what this means, see the example in the section "Example Demonstrating How to Use the +CMGS AT Command to Send SMS Text Messages in SMS Text Mode".

The <Ctrl+z> Character

When you finish entering the SMS message body, you have to enter the <Ctrl+z> character to mark the end of the SMS message body. The GSM/GPRS modem or mobile phone will then attempt to send the SMS message to the SMS center.

Previous Page

Page 45 of 65

Next Page