Rainbow Electronics GM862-QUAD-PY - Manual (Page 39)

Easy GPRS User Guide
80000ST10028 Rev. 4 - 16/07/08
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 39 of 63
Checking on the RFC990 the SMTP service we can found that the port 25 is dedicated for SMTP
service, therefore our SMTP server will be waiting for incoming connections on that port and we will fix
the EASY GPRS port to be contacted on the remote server exactly to 25.
Second thing we have to discover is whether the transport protocol has to be TCP or UDP; on the
RFC821 we can read that the SMTP Application layer protocol is meant to be on top of TCP/IP
protocol, therefore the transport protocol choice will fall on TCP.
Now we have all the information needed to configure our system.
The email can be sent following three different procedures:
1) Opening socket with SMTP server and then sending directly SMTP commands. The following
AT commands should be issued to the Telit module:
AT+CGDCONT = 1,"IP","internet.gprs","0.0.0.0",0,0<cr> (GPRS context setting)
For all the socket settings the following AT command will be used:
AT#SCFG=1,1,300,90,600,50
OK
Next step is activation of the GPRS context:
AT#SGACT=1,1,“EASY GPRS“,“EASY GPRS“
#SGACT: 193.199.234.255
OK
The command gives as response the IP address assigned by the network.
Now we can proceed with contacting the server with AT command for socket dial:
AT#SD=1, 0,25,"smtp.domain.com",0,0<cr>
When we receive the CONNECT indication, then we are exchanging data with the SMTP server
program on the remote host machine.
Following the SMTP protocol we proceed with the HELO presentation and mail delivery directly over
the serial line (in blu you can find the data sent by us, in violet the one received from host):
220 smtp.domain.com ESMTP Service (7.0.027-DD01) ready
HELO pcprova<cr><lf>
250 smtp.domain.com
AUTH LOGIN<cr><lf> (authentication method)