Motorola MTR2000 T5544 Instruction / Field Service Manual page 222

68P81096E53-C
09/30/05
Input Circuits
As shown in the block diagrams, the Auxiliary I/O Board contains SPI In-
put Buffers and associated circuitry which provides an input signal path
from auxiliary equipment to the station SCM.
The input circuitry comprises 16 general purpose inputs (GPI_0 to GPI_15)
of which 11 are available; 3 of these 11 inputs are dedicated inputs and 8
are user programmable (see Table 1 or RSS Online Help for details):
- GPI_0 to GPI_13 are transistor buffered inputs.
All transistor inputs can accept an open collector device from the aux-
iliary side. The impedance is 10 kOhm and if no open collector input
drive is used, the input withstands a pull up to maximum 16V.
- GPI_14 and GPI_15 are opto isolated inputs; rated at 2500Vrms isola-
tion. Input voltage between 15 and 50V to activate input.
GPI_14 can be configured as either an opto isolated or transistor input.
This input can also be jumpered to the SPI Latch or to the EXT_PTT SCM
direct input (jumpers P2 and P9). When jumpered to the EXT_PTT, GPI_14
is used as fast External PTT control. The External PTT line has a direct path
to the SCM in order to decrease reaction time by eliminating SPI process-
ing delay.
Table 1.
GPI# Auxiliary I/O (P1) Pin #
GPI_0 B26
GPI_1 C25
GPI_2 C24
GPI_3 C28
GPI_4 A28
GPI_5 B27
GPI_6 C26
GPI_7 C11
GPI_8 B28
GPI_9 C6
GPI_10 A24
GPI_11 B23
GPI_12 B22
GPI_13 B24
GPI_14 B7 or C5 + C7
GPI_15 A26 + C27
General Purpose Inputs
Backplane System
Connector (J5) Pin#
B7 Dedicated to Ext_Repeat input
A8 Not Supported (Do Not Use)
A9 Not Supported (Do Not Use)
A5 Wild Card input
C5 Wild Card input
B6 Not Supported (Do Not Use)
A7 Dedicated to Ext_Failsoft input
A22 Wild Card input
B5 Not Supported (Do Not Use)
A28 Wild Card input
C12 Wild Card input
B12 Wild Card input
B11 Wild Card input
B9 Wild Card input
B26 or A29 + A26 Fast Ext_PTT input or Not
Supported (jumper depen-
dent)
C7 + A6 Not Supported (Do Not Use)
Auxiliary I/O Board
GPI Function
5