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ROC364 Instruction Manual
4-7 Communications
Cards
Rev
Jun/05
4.2.5 Dial-Up Modem Communications Card
The Dial-up Modem Communications Card supports V.22 bis / 2400 baud communications with auto-
answer/auto-dial features. The modem card is FCC part 68 approved for use with public-switched
telephone networks (PSTNs). The FCC label on the card provides the FCC registration number and the
ringer equivalent. The modem card has automatic adaptive and fixed compromise equalization,
eliminating the need to adjust ports or move jumpers during installation and setup. Refer to Figure 4-6
and Figure 4-5.
The modem card interfaces to two-wire, full-duplex telephone lines using asynchronous operation at
data rates of 600, 1200, or 2400. The card interfaces to a PSTN through an RJ11 jack. The modem can
be controlled using industry-standard AT command software. A 40-character command line is provided
for the AT command set, which is compatible with EIA document TR302.2/88-08006.
The modem automatically hangs up after a configured period of communications inactivity. Automated
Dial-up Spontaneous-Report-by-Exception (SRBX) alarm reporting capabilities are possible with the
FlashPAC. Refer to the appropriate ROCLINK user manual for configuration information.
LED indicators on the card show the status of the RXD, TXD, DTR, DSR, RI, and OH control lines.
Refer to Table 4-1. The modem card also provides EIA-232 (RS-232) level output signals for an
analyzer at the COM1 or COM2.
Refer to Section 4.4.5, Dial-Up Modem Communications Card Wiring, on page 4-18.
DOC0389A
Figure 4-5. Dial-up Modem Communications Card – New
LED Indicators