20
ASYNC MP LINE DRIVER CARD
5.3.2 R
EMOTE
A
NALOG
L
OOP
The Remote Analog Loop test mode causes any characters sent from the remote
Line Driver Card to the local Card to be returned to the remote device (see
Figure 5-2
).
Start the test by pressing the Test button on one of the Cards. Then send data
from the other card (which must be in normal operating mode). If the data is
echoed back to the card in normal mode (for example, if characters you type
appear on your screen), the link to the Card in loopback mode is working.
NOTE
Only one Async MP Line Driver Card should be in test mode. The other
Card should be in “normal” operating mode or the test will not work.
If no characters are echoed back, check the wiring between the two Cards. Wire
the units according to the instructions in
Section 4.3
.
Figure 5-2. Normal operating mode vs. loopback operating mode.
RD
TD
TD
RD
Local 1060RC
In Normal Mode
Remote 1060RC
In Normal Mode
TX+
TX-
RX-
RX+
RX+
RX-
TX-
TX+
RD
TD
TD
RD
Local 1060RC
In Loopback Mode
Remote 1060RC
In Normal Mode
RX+
RX-
TX-
TX+
TX+
TX-
RX-
RX+
Local Async MP
Line Driver Card
in Normal Mode
Local Async MP
Line Driver Card
in Loopback Mode
Remote Async MP
Line Driver Card
in Normal Mode
Remote Async MP
Line Driver Card
in Normal Mode
