Carrier Access AB II manual Lcf

Analog Ports

D4 (SF) Framing Format

The following abbreviations are used in this table:

LCF - Loop current feed

RLCF - Reverse loop current feed

LCFO - Loop current feed open

LO - Loop Open

LC - Loop closure

RG - Ring ground

The interpretation of the signaling bits for ESF framing are as follows:

ESF Framing Format

See the legend at the end of this table for explanations of abbreviations.
Signaling Type	State		Receive (Network-to-				Transmit (CI-to-
			CI)				Network)
	Rx	Tx	A	B	C	D	A	B	C	D
Loop-start signaling	LCF	LO (on hook)	0	1	0	1	0	1	0	1
(FXO-FXS)
	Ringing	LC (off hook)	0	0	0	0	1	1	1	1
Loop-start signaling	LCF	LO (on hook)	0	1	0	1	0	1	0	1
with RLCF (FXO-
FXS)
	RLCF	LC (off hook)	0	1	0	0	1	1	1	1
	LCFO		1	1	1	1
	Ringing		0	0	0	0
Ground-start	LCF	LO (on hook)	0	1	0	1	0	1	0	1
signaling (FXO-
FXS)
	LCFO	LC (off hook)	1	1	1	1	1	1	1	1
	Ringing	RG (service	0	0	0	0	0	0	0	0
		request)
Ground-start	LCF	LO (on hook)	0	1	0	1	0	1	0	1
signaling with
RLCF (FXO-FXS)
	RLCF	LC (off hook)	0	1	0	0	1	1	1	1
	LCFO	RG (service	1	1	1	1	0	0	0	0
		request)
	Ringing		0	0	0	0
Loop-reverse-	LO	LCF	0	0	0	0	0	0	0	0
battery signaling
(DID) (DPO-DPT)
	LC	RLCF	1	1	1	1	1	1	1	1
Network-provided	LCF (on	LO (on hook)	0	0	0	0	0	0	0	0
reverse battery	hook)
(enhanced 911
apps) (DPT-DPO)
	RLCF (off	LC (off hook)	1	1	1	1	1	1	1	1
	hook)
E&M signaling	on hook	on hook	0	0	0	0	0	0	0	0
	off hook	off hook	1	1	1	1	1	1	1	1

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