STEPPIII Hardware description
Version 1.0.0
5 STEPPIII APPLICATION INTERFACE
5.1 Power supply
The power supply for the STEPPIII terminal has to be a single voltage source of
V
VC+
= +10.8 V...+32.0 VDC. It must be able to provide sufficient current
which
typically rises to
1.6
A
. The operating voltage (V
VC+
and GND) is protected
from reverse pole connection.
5.1.1 Power supply pins (15 and 16) on the MOLEX 16-pin connector
One VC+ pin on the MOLEX 16-pin connector is dedicated to connect the
supply voltage, 4 GND pins are recommended for grounding.
The VC+ and GND pins serve for charging the internal Li-Polymer battery and
powering the STEPPIII device. STEPPIII has
automatic power ON-function
when external power is applied. The power supply for the STEPPIII is capable
of utilizing current ranging from V
VC+
= +10.8 V ... +31.0 VDC
designed for
automotive application.
Signal name
I/O
Parameter
Description
VC+
I
+10.8 V...+32.0 VDC. The
operating voltage must never be
exceeded.
Positive operating voltage. This line must be
protected against overcurrent (by a 2A fuse)
and protected against over-voltage.
GND
-
0 V
Ground (should be isolated from the vehicle
Grounds)
5.1.2 Automatic shutdown
Automatic shutdown takes effect if:
•
the STEPPIII board is exceeding the critical limits of over or under
temperature.
•
the battery is exceeding the critical limits of over or under
temperature.
•
under voltage is detected.
The automatic shutdown procedure is equivalent to the power-down
initiated, i.e. STEPPIII logs off from the network and the software enters a
secure state avoiding loss of data.
5.2 Determining the External Equipment Type
Before you connect the serial port pins on the aforementioned terminals
(DCE units) to external equipment, you need to determine if the external
hardware serial ports are configured as DTE or DCE.
The FALCOM STEPPIII is designed for use as a DCE. Based on the
aforementioned
conventions for DCE-DTE connections it communicates with
the customer application (DTE) using the following signals:
STEPPIII Terminal (DCE)
to
Application (DTE)
Rx
<----------
TXD
Tx
---------->
RXD
Table 5:
The signalling definitions between DTE and DCE.
This confidential document is a property of FALCOM and may not be copied or circulated without previous permission.
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