Kongsberg Simrad EK80, Installation Manual

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Synchronization using Clear To Send (CTS) and Request To
Send (RTS) signals
In many applications, the synchronisation interface is based on an RS-232 serial port.
Only the Clear to Send (CTS) and Request to Send (RTS) connections of the RS-232
interface are then used.
According to the standard specifications for RS-232, an output must generate a voltage
level of +5 to +15 VDC (logic "low"), and -5 to -15 VDC (logic "high") into a load of 3
to 7 kΩ. An RS-232 receiver must present a 3 to 7 kΩ load , converting an input of +3 to
+25 VDC to logic "low", and an input of +3 to +25 VDC to logic "high". With a positive
trigger pulse, the offset voltage does not have any significance. Even small variations
(flutter) over and below 0 VDC will not trigger the interface.
A Local connection
B
Connection on remote device
C
Female 9-pin D-Subminiature connector
D Male 9-pin D-Subminiature connector
Note
RS-422 communication ports can not be used for
synchronization purposes. The port you wish to use must
be set to RS-232.
Related topics
Setting up the EK80 in a synchronized system, page 126
Cable layout and interconnections, page 85
Synchronization using the Auxiliary socket on the transceiver
The
Auxiliary
socket on the Wide Band Transceiver (WBT) offers a "trigger input"
signal for transmit synchronisation from an external system. This synchronization
method may be more stable that the traditional CTS/RTS connection to a serial port.
Normally, the EK80 transmits as soon as it is ready for the next "ping". When transmit
synchronization on the
Auxiliary
socket is enabled, the transmission is delayed until
a trigger pulse is detected on the input. The input trigger pulse must be a low-to-high
transition. "Low" level must be less that 0.7 V, while "High" must be above 2.8 V.
"High" level must not exceed 15 V! Once the trigger pulse is detected, the EK80 will
initiate transmission on all transceivers and frequencies.
Cable layout and interconnections