ZyXEL Communications 3356P Modem User Manual


 
Basic Modem Operation 9
Modem Result Codes
When you execute or try to execute an AT command, your modem sends a result code
to let you know whether the command was executed. An OK result code means the AT
command you sent was executed. If you receive an ERROR code, it means the
command was invalid.
The Comet also provides result codes that show:
Whether or not a Dial Tone was detected when the modem originated a call.
If a busy signal was detected when the modem originated a call.
The speed, protocol, and error control/data compression method used.
If your modem has detected an incoming ring.
Result codes can originate from any of eight result code sets. The
ATX
n and
ATW
n
command lets you choose which set of result codes your modem uses. By default, your
modem uses result codes equivalent to the
ATX4
and
ATW2
command.
Viewing S Register Values
Status registers (or "S-registers") contain values that determine the modem
s operating
characteristics. Whenever you send an AT command to your modem, you are actually
changing the value of an S-register.
You can use the
S
r
?
command to view the value of S-register
r
. For example, to
view the value of S-register S0, which controls auto-answering, type ATS0? and press
Enter. The modem responds with a three-digit character showing the value of this
register, followed by OK. A value of 002, for example, means your modem will auto-
answer incoming calls after the second ring.
Changing S Register Values
You can use the
ATSr=
n command to change the value of an S-register
r
.
For example, to have your modem auto-answer an incoming call after two rings, set S-
register 0 to 2. Be sure the n value is between 1 and 255. If n is set to 0, your modem
will not answer incoming calls.
Non-Volatile Memory
The Comet has memory set aside for storing user information such as frequently used
phone numbers and default command settings. This section covers the topics of storing
phone numbers, and saving default settings in the power-on profile.
Storing Phone Numbers
The AT command to store a phone number is in the format
AT&Z
s
=
n.