\
NPE
●
ON-BOARD
MICROPROCESSOR
PORT
I/O
CIRCUIT
GROUND
DETECTOR
T.O
R.O
●
PORT
S.0
CIRCUIT
S1.0
0
SZ.0
SZ1.0
I
I
I
I
I
TO
AUXILIARY
EQUIPMENT
●
❘
T.3
R.3
PORT
S.3
CIRCUIT
S1.3
3
SZ.3
SZ1.3
/
Figure 3-18. Unique Auxiliary Trunk (TN763) Circuitry
3-36