GatesAir
DA-191B Four-Port Asynchronous Data Module
Intraplex Products
Version 1
2
Section 2
Functional Description and Setup
2.1
General
Figure 2-1 shows a simplified block diagram of the DA-191B.
The green
SRVC
LED lights when service is turned on for the module, even if no channel is
actually transmitting or receiving data. (SRVC will go off in an E1 multiplexer if timeslot 16 is
selected for use in a CAS formatted signal.)
The
T1
switch allows the user to set the module for use in a T1 or E1 multiplexer, and the
CAS
switch, used in an E1 multiplexer only, determines whether time slot 16 is reserved for CAS
signaling.
The
TERM
switch determines whether the module is set up for use in a terminal multiplexer or a
drop/insert multiplexer. In a drop/insert multiplexer, it also determines whether the module
communicates via the DI-A port or the DI-B port (see Section 2.5,
Drop and Insert Operation
).
RATE
and
MODE
switches set the maximum data rate and whether the module uses one, two,
four, or eight time slots. Table 2-1 shows the relation between the data rate, which data ports are
activated, and the number of time slots required. The
TIME SLOT SELECT
switches determine
which time slot(s) are used.
Table 2-1
Data Rate and Time Slot Usage
Maximum
Data Rate
Active Ports
Time Slots Required
38.4 kbps
1
2
38.4 kbps
1 and 2
4
38.4 kbps
1 to 4
8
19.2 kbps
1
1
19.2 kbps
1 and 2
2
19.2 kbps
1 to 4
4
9.6 kbps
1 and 2
1
9.6 kbps
1 to 4
2