User guide
38
Chapter 3 - Software Installation
3.9.4 Optional Settings
•
Data TEI
The Data TEI is the TEI (terminal endpoint identifier) assigned to the data channel. Select
Auto TE
I, a
fixed TEI, or
Disable
. A TEI is a number used by the central office switch to uniquely identify each
device connected to the network. When it uses dynamic TEI assignments (Auto TEI), the central office
switch assigns a TEI each time the TA connects to the network. However, the ISDN service provider
may assign a fixed TEI at subscription time, in which case you must configure the TA with the fixed TEI
number. You also can disable the channel, which may be useful when multiple TAs are attached to a
network terminator bus.
AT command: !D3=
•
Voice TEI
The Voice TEI is the TEI assigned to the voice channel. You have the same choices as for Data TEI:
Auto TEI
, fixed TEI number, or
Disable
.
AT command: *!D3=
•
Persistent DTR Dialing
A high DTR (Data Terminal Ready) signal on the serial port indicates that your computer or terminal is
ready to communicate with your TA. DTR normally goes high when a communication program starts or
is ready to dial. Persistent DTR dialing enables the TA to automatically redial the number stored in
memory location 0 whenever DTR is high, and the serial port does not have an active call. You can
enable or disable this feature.
AT command: $D
•
Auto Answer Data Calls
Rings to Answer
Select Auto Answer if you want the TA to automatically answer all incoming data calls (option does not
affect analog port). The Rings to Answer number (range: 1—255) selects number of rings the TA waits
before answering an incoming call. Default: 1 ring.
AT command: S0=
•
Dialing Method
Select either the
Enbloc
or the
Overlap
dialing method for use when establishing a data call. Your ISDN
provider determines the dialing method. The enbloc method is used for most ISDN dialing. Select the
overlap method if you are working with a private network.
AT command: %A97=
•
Data Protocol
The data protocol, also known as the B-channel protocol and the rate adaptation protocol, is the
language
spoken over each 64 Kbps channel between two ISDN devices. The devices on both ends of
the ISDN link must use identical protocols.
AT command: !Z
•
V.120 Protocol( !Z = 5 )
—for rates up to 64 Kbps on each B channel.
•
PPP Protocol ( !Z = 9 )
—for rates up to 64 Kbps on each B channel.
•
X.75 Protocol
— The ISIHP uses layer 2 of the X.75 protocol as an error correction protocol
on the B-channel.
•
Stored Numbers
The TA can store as many as 10 phone numbers, up to 20 characters each.
AT command: &Z=
•
Dialing Stored Numbers
The TA can dial a number previously stored in directory number
n
using the
&Zn=x
command.
AT
command: e.g., DS3