Xerox FaxCentre F110, Service Manual

Page: 159 / 204

General Procedures / Information
FaxCentre F110 12/04 6-73
LIU_HOOK:
External phone Connection, controls output the relay. This signal is used to establish a line con-
nection (
LA2,LB2 ) between the FAX system (Terminal Equipment, TE) and the Ext. phone
Loop current status (LOOP) changes if HOOK changes !
When not powered, the relay should connect the external phone to the line. At start-up the
firmware activates the relay to connect the LIU.
PD: Pulse Dial
This signal is used to generate line (loop current) connections and disconnection. If inactive (Low)
no connection between the line and the terminal equipment exists.
Loop current status (LOOP) changes if PD changes !
LIU_CURMOD:
Current Modulation. The signal is used during Pulse Dial only to enhance the switching charac-
teristics of
PD (Loop Current). Keep activated during dialling of a complete digit. Not activated if
flash is dialed.
Table 4:
HOOK State
0 On-Hook (External phone connected)
1 Off-Hook (External phone disconnected)
Table 5:
Line State HOO
K PD
On-Hook 0 0
Off-Hook 1 1
Off-Hook (dialling) 1 1,0
Table 6:
PD State
1 Make (Line connected
0 Break (Line disconnected)
Table 7:
CURMOD State
0 Default , no current
1 Loop current enforced