Verilink PRISM 3030 (34-00208.L) Product Manual - Manual (Page 100)

90 A PPENDIX B: FXS V OICE A PPLICATION M ODULE
The FXS application module responds only to the received A signalling bit and the
B signalling bit is ignored. The FXS application module applies two seconds ON
and four seconds OFF ringing to the CPE and ring back tone two seconds ON and
four seconds OFF toward the network (only when the loop from the CPE is open
and the receive A signalling bit changes from a 1 to a 0).
UVG UVG must use a Verilink FXO with the FXS in UVG mode. In UVG mode, the
FXO/FXS application modules automatically detect if they are in a loop start or
ground start circuit and operate appropriately.
UVG with
Reverse Battery UVG with reverse battery must use a Verilink FXO with the FXS in UVG mode.
In UVG mode, the FXO and FXS application modules automatically detect if they
are in a loop start or ground start circuit and operate appropriately. With reverse
battery enabled, a battery reversal from the CO is passed to the CPE.
DID/DNIS In DID and DNIS operation, an FXO application module in DPT mode is
connected to the CPE equipment. The CPE equipment must be capable of
supplying loop current to the FXO application module. An FXS application
module in DPO mode is connected to the CO and supplies loop current to the CO.
Both DID and DNIS are inbound-only services (from the CO to the CPE).
Idle
State
The FXS application module provides ground to tip and
−
48V to ring towards the
CO. The FXS transmits A and B signalling bits = 0 towards the network, receives
an A bit = 0, and ignores the B bit.
Call Originated
from CO
The CO seizes the line by closing tip to ring. The FXS recognizes the loop closure
and transmits A and B signalling bits = 1.
CPE
Answer
The CPE recognizes the seizure and responds with a wink. During the wink, the
FXS receives an A bit = 1 and ignores the B bit. While the A bit = 1, the FXS
outputs a battery reversal to tip and ring.
Digit
Transmit
After the wink, the CO passes digits to the CPE as DTMF tones or as pulses.
DTMF tones are passed as voice frequency data to the CPE. Dial pulses are passed
to the CPE by sending both A and B signalling bits = 0 during the break interval
and by sending both A and B signalling bits = 1 during the make interval.
CO
Terminate
The CO terminates the call by opening the loop. The FXS transmits both A and B
signalling bits = 0.
Loop Start DNIS
with Wink In Loop Start DNIS operation, an FXS application module in LS-DNIS mode is
connected to the CPE equipment. Another FXS application module in DPO mode
is connected to the CO and supplies loop current to the CO. The DNIS service is
inbound only (from the CO to the CPE). Outbound calls are handled as
MEGACOM or MEGACOM with Reverse Battery.