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Operator Manual
Issue 1
TIL – Eng – Spec – 080
Page 65 of 70
SeaHub
My serial port device doesn’t
work in RS485 mode
•
Check A and B wiring connections are correct on both ends
or any interconnect cabling, and not crossed.
•
Check that baud rates and serial setup on both the device
and the PC are correct
•
Check the cable length used does not exceed the stated
RS485 specification for the baud rate being used.
•
Check that nothing is shorting out the RS485 signals, and
voltage levels are 5V.
•
Check the port is correctly configured as RS485 mode
through the Seanet Setup configuration interface.
•
Check that the correct termination has been fitted to the
cable (approx 150
Ω
).
•
Check that the half-duplex turnaround time is less than a ½-
baud period on the RS485 device.
•
If the device is drawing power from the SeaHub, check that
the power supply requirements for either the AC (Mains) or
DC source have not been exceeded.
My serial port device doesn’t
work in RS422 mode
•
Check that Port B is being used, as this is the only port that
supports RS422 mode.
•
Check RX and TX connections (with A and B pairs in each)
are correct on both ends of any interconnect cabling.
•
Check that baud rates and serial setups on both the device
and the PC are correct
•
Check the cable length used does not exceed the stated
RS422 specification for the baud rate being used.
•
Check that nothing is shorting out the RS422 signals, and
voltage levels are 5V.
•
Check the port is correctly configured as RS422 mode
through the Seanet Setup configuration interface.
•
Check that the correct termination has been fitted to the
cable.
•
If the device is drawing power from the SeaHub, check that
the power supply requirements for either the AC (Mains) or
DC source have not been exceeded.
The RAT does not work
•
Check that the RAT being used is labelled as a “Version 2,
PS-2” RAT. The SeaHub unit does not support previous
versions (i.e. With Trackball instead of Togglestick pointer).
•
Check that the connection of the RAT has not caused the
power supply requirements for either the AC (Mains) or DC
source to be exceeded.