Xerox FaxCentre F110, Service Manual

Page: 164 / 204

General Procedures / Information
6-78 12/04 FaxCentre F110
GP 35 INTLOOP Signal
Loop Current Detection
The activation of a On-Hook or Off-Hook Configuration, a parallel Terminal equipment On- or Off-
Hook change, an External Terminal equipment On- or Off-Hook change and Pulse Dial activity
change the loop current accordingly. This signal can change only if the LIU is connected to the
line (LIU_HOOK=1).
Table 1: Loop Detection Table
LIU state LIU_HOOK PD INTLOOP EXTLOOP LOOP Current External Phone
Onhook / Loop 0 0 0 1 NO LOOP EXT. PHONE
Onhook / No Loop 0 0 0 0 NO LOOP NO EXT. PHONE
Offhook / Handset lifted 1 1 1 0 LOOP DET. INTERNAL
Offhook / Pulse Dial 1 X X 0 LOOP DET. INTERNAL
Offhook / DTMF Dial 1 1 1 0 LOOP DET. INTERNAL
Offhook / FAX 1 1 1 0 LOOP DET. INTERNAL
Offhook / No Loop 1 1 0 0 NO LOOP INTERNAL
line
DC-voltage
- 40V
0V
+ 40V
LIU_RING
offhook (internal)
onhook (internal)
LIU_HOOK
LIU_PD
INTLOOP