ADTRAN ISU 2x64, User Manual

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Chapter 6. Configuration
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ISU 2x64 Dual Port ISDN Service Unit User Manual 61200051L1-1D
The first byte of each packet contains all ones (A = FF HEX), and
the second byte of each packet (the C byte) is either 13 HEX or 03
HEX if not the final packet.
V.25 SYNC BISYNC Dialing
To set the Dial Options for V.25 BISYNC, choose 3=V.25 BISYNC
from the front panel or the VT 100 terminal (see Figure 6-8 for
menu tree). This setting allows for V.25 bis messages in byte syn-
chronous format (BISYNC). V.25 bis specifies that the characters
should be ASCII, 7 bits, and odd parity. This setting allows syn-
chronous data terminal equipment which does not use HDLC to
support serial inband dialing.
V.25 HDLC FLAG
To set the Dial Options for V.25 HDLC FLAG, choose 4=V.25
HDLC FLAG from the front panel or the VT 100 terminal (see Fig-
ure 6-8 for menu tree). Configuring the ISU 2x64 for HDLC
FLAG V.25 bis enables in-band dialing over a DTE interface using
standard synchronous HDLC V.25 bis commands with 7E HEX
idle.
Disabled
This selection disables in-band dialing over the DTE interface.
Setting Auto Answer
Auto answer is configured separately for both DTE#1 and
DTE#2. Using the front panel, select the appropriate DTE with
either arrow key and press
Enter . When using a VT 100 terminal,
select the option number corresponding to the appropriate DTE
and press
Return .
The ISU 2x64 can be configured to automatically answer in one of
three ways: Disabled, Enabled, or Dump all calls.
Disabled
When Disabled is selected, the ISU 2x64 will not answer the call.
The AT answer command (ATA) must be issued to the ISU 2x64
for it to accept the incoming call or by selecting
Answer Call
from dial menu. The ringing call can be dumped by using the