Psion 8585, Руководство пользователя

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Psion 8585/8595 Vehicle-Mount Computers User Manual
Chapter 5: Operation
Automatic Switch-off
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5.6.4.1 Problems with Data Transmission via LAN/Ethernet
If problems occur during data transmission over LAN/Ethernet (e.g. data is lost or not detected), the cause
of these problems may be a cable which is too long.
Depending on the cable layout and interference from the environment, it may be impossible to use the
cable length of 100 m given in the specification (IEEE 802.3 standard).
The solution here is the use of a shorter cable.
5.6.5 Automatic Switch-off
The 8585 is equipped with an automatic switch-off module.
5.6.5.1 Modes of Operation
If wired up accordingly, the 8585 conveniently switches off together with the vehicle's ignition.
As disconnecting the power supply during operation can lead to data loss, the operating system needs to be
shut down normally using the appropriate hardware and software installed on the system when the ignition
is switched off.
The 8585 is connected to the vehicle with three supply cables. DC+ and DC– are directly connected to the
power supply of the vehicle, the connection is run through fuses. Therefore make sure that the cables are
connected directly to the battery and not to high-interference supply lines (for example, motor supply) or to
supply lines already used by other consumers.
The supply voltage connected is then linked to the 8585's ignition input via a switch, for example, the key
switch of the ignition (also with a fuse).
5.6.5.2 Automatic Switch-off Process
When the ignition is switched on, the 8585 is supplied with power and begins checking its internal temper-
ature and automatic switch-off function.
Once the ambient conditions have been verified as acceptable, the 8585 starts the operating system just
like normal.
During the first three minutes of the start-up phase, none of the ambient conditions, such as the internal
temperature or the
Ignition input status, are checked. This allows the operating system and the operating
software for the automatic switch-off module to fully load without interruption.
Following this three-minute period, the internal temperature of the unit and the status of the Ignition input
are checked continuously.
If the inner temperature of the 8585 reaches a critical range, the operating system is shut down normally
and the computer remains switched off until the temperature is back in the permitted range.
If the Ignition input is switched to earth potential or a potential-free source during normal operation, the
unit switches to shutdown delay time.
In this state, the device continues to operate normally until the delay time (for example, 15 minutes) has
elapsed.
• If the ignition is triggered again during this time, the 8585 resumes normal operation.
• If, however, the delay time elapses, the operating system is shut down normally by the Psion operating
software and the unit is automatically switched off (for example, after three minutes, or after a signal
from the operating software).
5.6.5.3 Configuration with Psion Config Program
The Psion Config program must be installed for the automatic switch-off module to function correctly.
If the Psion Config has not been started, the 8585 will carry out a hard shutdown once the delay time and
shutdown time set by the hardware (e.g. via MPCCOM.EXE) has elapsed. In this case, the operating system is
not shut down normally before the power is switched off. The current application is unable to save its data,
and the file system becomes increasingly unstable and inconsistent.
If the Psion Config has been started, the program can recognize when the operating system needs to be
shut down. Firstly, the Windows message WM_QUERYENDSESSION is sent to all running applications to
inform them of the impending shutdown.