Psion 8585, User Manual

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Psion 8585/8595 Vehicle-Mount Computers User Manual
Chapter 5: Operation
Tips and Tricks
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7. Click OK again for the changes to take effect.
5.5.4 Tips and Tricks
Note that according to the EIA-232-E specification, the maximum cable length is 15 m at 19,200 bps.
By using a correctly terminated twisted-pair cable, however, up to 1,200 m at 100 kbps can be achieved ac-
cording to the EIA-422-A specification. With a data rate of 1 Mbps and a high-quality cable, it is possible to
reach cable lengths of up to approximately 400 m.
Malfunctions in the RS-232 connections are frequently caused by ground loops. If both end devices estab-
lish a ground connection via RS-232 but do not share the same ground potential in their power supply cir-
cuits, then compensation currents may result. This is particularly noticeable with long cables.
These compensation currents, which are also present at the ground point of the RS-232 connection, may
significantly degrade signal quality and effectively stop the data flow. In challenging environments, electri-
cally-isolated connections (via external converters) or differential systems (RS-422/485 port) are strongly
recommended.
5.6 Internal Devices
5.6.1 Chipset
The 8585 computer is equipped with a chipset which controls the communication between all function
modules.
The chipset converts the signals it receives from the CPU into memory access, flash access and other
similar actions. Likewise, it transmits requests from peripheral devices to the CPU. Input devices such as
the mouse or keyboard also communicate with the system via this chipset.
5.6.2 VGA Adaptor
The 8585 is equipped with a VGA-compatible adaptor. This adaptor controls the integrated display.
5.6.3 Onboard Sound Controller
The 8585 is equipped with an onboard sound controller.
This controls the audio output via the internal speaker, or the optional Speaker/Mic with push-to-talk func-
tion (Model Number M1000).
5.6.4 Network Adaptor (10/100/1000)
The 8585 is equipped with a 10/100 Mbit network adaptor. This adaptor features an RJ45 port.
The network controller undertakes the entire task of connecting the hardware to the network.
The RJ45 connection port features two integrated status LEDs. They display the following messages:
Figure 5.3 RJ45 network port
Caution:
Property
Damage Please note that you have to configure the scanner correctly to RS-232 and the above set
BAUD rate following the scanner manufacturer's guidelines. Otherwise the software wedge
will not function properly.
Left LED (green)
LED off: not connected
LED on: connected
Right LED (orange)
LED off: no activity
LED flashes: activity