TM
COMSPHERE 3900 Series Modems
Models 3910 and 3911
Firmware Update Description, Release 2.61
Document Number 3910-A2-GK61-10
November 1996
Overview
This document describes new features and changes that occurred in the Model 3910 and Model 3911 modems as a
result of Firmware Release 2.61. Information in this document is intended to be used in conjunction with the
COMSPHERE 3900 Series Modems, Models 3910 and 3911, Point-to-Point/Multipoint, Installation and
Operation Manual, Document No. 3910-A2-GN32.
Ordering Information
Call your sales representative to order additional product documentation.
Leased Line Configuration Options
The following information replaces the Auto Dial Back, Leased Mode, and TMp TxPreemphasis configuration
options of Table 4-5, Leased Line Configuration Options.
Auto Dial Back: Disable
Nxt Disable Enable Circular
This configuration option is not available if the LeaseLine Rate is configured for TMp and the
NetworkPosition is configured for Control.
Automatic Dial Backup. Allows the modem to dial numbers stored in directory locations to restore
communications with the remote modem when the leased lines fail.
NOTE: In point-to-point applications, this configuration option must be set to Enable or Circular in both the
local and remote modem. The answering modem must have its Auto-Answer Ring Number
configuration option enabled. Refer to the Line Dialer configuration option group for information on
Auto-Answer.
NOTE: When this configuration option is enabled, the originating modem attempts a dial backup for a limited
number of calls (regulations vary, based on the country). The call-limiting function resets upon
completion of a manual dial backup, a power cycle, or when using the Reset command from NMS.
For example, in some countries the limitation is ten call attempts to the same number, with two
minutes delay between calls. If the call is not successful after the tenth attempt, the modem waits
two hours, then resumes calling.
Enable
The modem will dial the first number in directory location one (1). If the call fails, the modem
continues to dial the number in directory one every two minutes (or more, if required by country
regulations).
1
Circular
The modem dials the number in directory one (1). If the call fails, the modem dials the number in
the next directory location until it is successful. The modem returns to directory one when it
encounters an empty directory or the last directory (24).
The AT command is S-Register S46=n, where n is 0 for Disable, 1 for Enable, and 2 for Circular.
Leased Mode: 4WLL-Ans
Nxt 4WLL-Ans 4WLL-Orig 2WLL-Orig 2WLL-Ans
Leased Mode. Sets the modem for either 2-wire or 4-wire operation in Answer mode (receiving a call) or
2-wire or 4-wire operation in Originate (initiating a call) mode.
NOTE: For proper operation of V.32 modulations over leased lines, one modem must be set to Originate
mode and the other set to Answer mode.
For Sync Leased Answer Mode, Async Leased Answer Mode and Trellis Multipoint Control Mode, 4-wire
Answer is the factory default.
For Sync Leased Originate Mode, Async Leased Originate Mode and Trellis Multipoint Tributary Mode,
4-wire Originate is the factory default.
The AT command for Disable is &L0.
The AT command for 2-wire Originate is &L1.
The AT command for 4-wire Originate is &L2.
The AT command for 2-wire Answer is &L3.
The AT command for 4-wire Answer is &L4.
TMp TxPreemphasis: Disable
Nxt Disable Enable
This configuration option is only available if LeasedLine Rate is configured for TMp.
Trellis Multipoint (TMp) Transmit Preemphasis. Provides amplification for frequencies above the carrier
frequency to compensate for high frequency line attenuation.
The AT command is S-Register S96=n, where n is 0 for Disable and 1 for Enable.
2
Miscellaneous Configuration Options
Add the following configuration option to Table 4-8, Miscellaneous Configuration Options.
Mixed Trib F/W: No
End No Yes
This configuration option is only available when the modem is configured for TMp Control.
Mixed Tributary Firmware. Establishes that a multipoint network has TMp tributary modems using firmware
prior to Release G02.60.xx.
No – Multipoint network modems do not have mixed firmware.
Yes – Multipoint network modems do have mixed firmware.
391x Series S-Registers
The following information replaces S-Register S46 of Table 5-4, 391x Series S-Registers.
S46
Auto Dial Backup. Register determines if the modem performs an
automatic dial backup if the leased lines fail.
Configure\Edit\
Leased Line
Register has the following values:
0 = Disable
1 = Enable
2 = Circular
The factory setting is Disable.
Factory Default Configuration Options
The following information replaces the TMp Tx Preemphasis factory default of Table F-1, Factory Default
Configuration Options.
Configuration
Option
Sync
Leased
Default
Settings
Async
Leased
Default
Settings
TMp
Default
Settings
Async Dial
Default
Settings
UNIX Dial
Default
Settings
Sync Dial
Default
Settings
Leased Line
TMp Tx
Preemphasis
N/A
N/A
Disable
3
N/A
N/A
N/A
Dial Access Security
The following instructions are an addition to the self-supporting page in the back of Chapter 6, Dial Access
Security.
To clear the dial access security alarm light from the modem’s front panel, do the following:
1. Press the
key to return to the Top-Level menu.
2. Press F1 to access the Status branch.
3. Press F1 again to select DeviceHs.
4. Press F3 to select Security.
5. From the Security branch, press F1 twenty (20) times. The security alarm light clears.
4