Chapter 3 – SMTP/POP3 Email Services
Multi-Tech Systems, Inc. AT Commands for Wireless Modems with IP Connectivity (S000333D)
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#DNSSERV2 Set Secondary DNS Server
Definition:
In order to translate the server names from literal format into IP addresses, the TCP/IP stack software
implements the Domain Name System (DNS) protocol. The DNS Server IP address has to be specified
for use by the TCP/IP stack software. This secondary DNS server is used in the case where the primary
DNS server does not respond to a request
.
Values:
32-bit number in dotted-decimal notation (i.e., xxx.xxx.xxx.xxx).
Default 0.0.0.0
Syntax:
Set Value: AT#DNSSERV2=<value>
Get Value: AT#DNSSERV2? or AT#VDNS, AT#VALL
#GETMAIL Retrieve Host Mail
Definition:
This command allows the attached host to direct the TCP/IP stack to retrieve the first mail present in the
POP3 server list. Once an IP link is established, the attached host can retrieve an email message at
any time (except when the TCP/IP stack software is already in a process using TCP resources). This
command is similar to a “check email box” feature issued by a standard messaging client on a PC.
Values:
Read
Parameters:
POP3HEADERMODE
POP3PORT
POP3UN
POP3PW
POP3SERV
Syntax:
AT#GETMAIL
Command
Possible Responses
AT#GETMAIL
Note: Retrieve
mail
OK_Info_Mail
<mail content>
Notes:
This message is issued when one email message is located in the specified
POP3 mailbox.
Depending on the POP3HEADERMODE parameter, the TCP/IP stack sends
the email header over the serial port to the attached host.
The (CR)(LF)(.)(CR)(LF) sequence finally indicates the end of the email body.
AT#GETMAIL OK_Info_NoMail
Note:
There is no email to retrieve in the POP3 mailbox.
AT#GETMAIL
#CME ERROR: 38027
Notes:
The address of the POP3 server has not been resolved by the secondary DNS
server.
TCP/IP stack is not able to reach the primary and secondary DNS servers or a
wrong POP3 server address has been filled in.
AT#GETMAIL
#CME ERROR: <value>
Notes:
An error has occurred during the communication with the remote POP3 server.
It may also happen during the data transfer after the MAIL message. In this
case, it is preceded by a (CR)(LF)(.)(CR)(LF) sequence.
This error can be due to one of the following reasons:
- The DNS servers are not able to resolve the POP3 server address
- The POP3 server is temporarily out of service
- The authentication (POP3UN, POP3PW) is not valid
See section ‘ Response messages and error codes’.
