Carrier Access SNMP manual Termination Options, Foreign Exchange Office FXO Termination

12-Channel FXO & Dial Pulse Termination Card

FXO or DPT termination. Also on the card, each individual channel has a two position switch for the selection of ground start or loop start (see Figure 9-3) and a 6-section DIP switch to control the line attenuation (see Channel Attenuation Options).

10.3 Termination Options

The FXO/DPT card can be configured for use as either an FXO or DPT interface card. Further, FXO offers both ground start (GS) and loop start (LS) modes of operation. These options require the set- ting of one switch per channel (12 per card) and one 4-position Dual Inline Package (DIP) switch per card (see Table 10-1,and Figure 9-3). Note that in the table, a 1 indicates the switch is on, while a 0 indicates the switch is off. The slide switch on the 12-channel analog card for each channel indicates whether that channel is set to GS or LS mode. The DIP switch determines whether the card will use FXO or DPT termination.

Note: When DPT is selected, the large slide switches for each channel must all be set to LS. However, when FXO termination is chosen, either LS or GS can be selected for each channel.

Table 10-1: Termination Options and Switch Settings for the FXO/DPT

Trunk Signaling	4-Position DIP Switch	Slide Switch
	per Card	per Channel
FXO Ground Start	0000	GS
FXO Loop Start	0000	LS
DPT	1000	LS

10.3.1 Foreign Exchange Office (FXO) Termination

The FXO provides private branch exchange (PBX) office end connectivity to public network T1 lines. The FXO acts as a sink for a battery source, detects ringing, provides outgoing seizure, pro- vides and interprets A/B bit signaling to and from the T1 line, and enables two-way voice frequency transmission.

10-2 9/24/01