Sierra Wireless AirLink MP, User Manual

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Hardware and Software Installation
Rev 1.0 Mar.10 33
Typically a digital input device should be connected between Ground (Pin 10) and
the input port (Pin 3, 4, 11, or 12).
Figure 3-11: A button wired to Pin 4 (digital input) and Pin 10 (Ground).
The pins report a logic high on an input of 3.45 VDC. An internal pull-up resistor
provides a high condition when the switch is open.
The digital input pins report a logic low on an input between 0 VDC and 0.8 VDC.
Sinking the input pin to ground yields a logic low (0x00) when the port is polled.
If you configure the MP modem to send data to a network server, digital input
data can be remotely monitored.
Example: panic button connections
An I/O cable for a panic button requires a wire to one of the digital input or I/O
pins (such as #3) and one wire to the Ground pin (#10).
Digital output devices
Digital output devices are those that have only two states and the state is
controlled by a signal from the MP modem. Any device that is to be switched on
and off from ACEview would be installed as a digital output device.
A digital output can be connected to two of the pins on the DB15HD connector:
Pins 3 and 11. (These can be used for either input or output.)
Note: Before using the input/output lines, you must configure them as inputs or outputs.
Typically a digital output device should be connected between Ground (pin 10)
and the output port (Pin 3 or 11).