Onyx.
Advanced car security solutions
16 Shapira St. Rishon Le - Zion 75052, Israel
Tel: 972-3-9413313 ; Fax: 972-3-9413330
www.onyxtech.co.il ; [email protected]
Page 6 of 12 EGPRS Unit User Guide
2.3
Peripheral communication
The Micro controller interfaces with the alarm system over the RS-485 channel
and with the GPS over the RS-232 channel. The eNet bi-directional channel is
able to carry information between various sensors and devices connected to the
bus.
The charger is fed from the car battery to charge the internal backup battery.
The internal backup battery has the ability to be used for up to 10 hours under
normal operating conditions when external power is disconnected. The EGPRS
utilizes status triggered charging algorithm in order to not harm the internal
batteries.
2.3.1
RS-232
This serial communication protocol supports communication over a common
data line. The EGPRS Micro controller communicates with the GPS device over
this data line.
2.3.2
RS-485
The EGPRS Micro controller communicates with the alarm system devices over
the RS-485 data line.
2.3.3
eNet
This bi-directional serial communication protocol can be used to connect
peripheral devices to the EGPRS such as: alarm units, a portable printer,
warning lights, distress buttons, and more.
One of the Open Collector/eNet single line interfaces can be configured as
eNet. The eNet bus must have a single master and up to 10 slave devices.
2.3.4
Single Wire Discretes
The EGPRS supports six single line interfaces (Inputs only) of types as listed
below:
•
3 General Purpose Input Discrete – one of which can be used for VSS
Odometer measuring, and one optionally supports eNet bi-directional
communication (See above).
•
1 digital output – 12v active 200ma.
•
1 Ignition line (dedicated Input discrete).
•
1 that can be used as an input or output (according to configuration) and
can be defined to digital or analog.