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CHAPTER 9: Data-Channel Configuration
99
Table 9-11. Asynchronous Channel Features
Option
Default
Description
1.
Priority
High
Determines whether port is high or low priority in reference to other async
ports. (Async channels always have lower priority than voice/fax or sync
channels.) Keep the port’s setting to high priority where an interactive
(terminal and host) connection needs quick response time. Configure for
low priority when a fast response to data transfer is not required, such as
for a printer.
2.
EIA Control
Enable
Offers the option of recognizing or ignoring the control signals from the
attached device. When EIA Control is enabled, the Multiserver recognizes
and responds to channel interface control signals. When EIA Control is
disabled, the output is forced
high
and RI is forced
low
.
If you are configuring DTR or Auto from the Connect Protocol Menu (see
Section 10.7, Asynchronous-Channel Switching Parameters
), EIA
control must be enabled.
3.
Smooth Scroll
Off
This option should remain off for all devices other than DEC VT100
Smooth Scroll terminals. When this option is
on
, the Multiserver requires
an explicit X-ON character (after an X-OFF has been received) before
transmission of data to the port is resumed.
4.
Tandem
No
The
no
option is for all connections except for Tandem
®
host
configuration. Supports Tandem Non-Stop computer data flow operation.
The
yes
option is required at the host end for Tandem support. Other
async channel characteristics and features must also be specifically
configured to enable Tandem computer support for a user channel. Refer
to
Appendix F
for additional information, and also see
Appendix B
for
Tandem cabling information.
5.
Flow Control Strip
Pass
When
strip
is selected, the flow control signals from the user are not
passed by the Multiserver. This is useful in the case of X-ON/X-OFF
characters that do not match at either end of the channel. When
pass
is
selected, X-ON/X-OFF and DTR flow control output by the user is passed
by the Multiserver to the network. DTR is output at the other end as DSR.
6.
HP ENQ/ACK
No
The
no
option is for all connections except for Hewlett Packard
®
HP3000™ View Systems. The
yes
option is required at the host and
terminal ends for HP3000 support. (However, the
no
option is required for
spool-mode printers. Flow control must be set to
none
in this particular
case.) Refer to
Appendix F
for additional information on other
configuration requirements for HP3000 support.
7.
Sync Loss
No
This feature offers the option of dropping the channel connection in the
Disconnect
event the interconnect or mux link is dropped. If
yes
is selected, the
Multiserver will disconnect the channel 40 seconds after the system
senses loss of sync on the link. All data in the buffers for the port are
discarded and all control signals are dropped. This is a valuable function
for tail-end modem connections. If
no
is selected, the Multiserver will not