Description
10
68P81096E36-H
06/28/05
Auxiliary I/O Board Operation
Introduction
The Auxiliary I/O Board serves as the interface between the customer auxiliary
equipment and the Station Control Module (SCM). In general, the Auxiliary I/O
Board routes all auxiliary equipment control signals between the SCM and the aux-
iliary equipment (e.g., a trunking controller).
Auxiliary I/O Board Operation
The Auxiliary I/O Board contains SPI Input Buffers and associated circuitry which
provides an input signal path from auxiliary equipment to the station SCM.
The input circuitry supports 16 general purpose inputs:
-
14 are transistor buffered inputs; 16V maximum, 10k
Ω
.
-
2 are opto isolated inputs; 60mA forward current, 3V dropout voltage, 2kV iso-
lation.
The Auxiliary I/O Board contains SPI Output Latches and associated circuitry which
provides an output signal path from the station SCM to auxiliary equipment.
The output circuitry supports 16 general purpose outputs:
-
14 are open collector transistor outputs; maximum 40V, 100mA sink current
-
2 are dry contact outputs (relay); maximum 250V, 1A)
Not all inputs and outputs are supported, see
Table 4, on page 33 through
Table 8, on page 37.
Note
