Kongsberg Simrad ES80, Installation Manual

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Synchronization sequences
In many applications, the synchronisation interface is based on an RS-232 serial port. When
you connect two systems for synchronisation using Clear to Send (CTS) and Request to
Send (RTS), one system must set up as a "Master" and the other as a "Slave". When the
ES80 is "Master" in a system, the synchronization can either take place in
Free running
mode, or in Wait for slave mode.
Slave mode
When the ES80 is set up in Slave mode, it must receive a trigger signal from a peripheral
system every time the ES80 is going to transmit. This trigger signal is connected to a serial
port on the Processor Unit, and the
Clear To Send (CTS) pin is used to give the ES80 an
"event" message. The message is processed by the ES80 software, and it will (if the previous
ping has been finished) start the ping sequence.
As an acknowledgement to the synchronization trigger, the ES80 sets the Ready To Send
(RTS) signal to a logic "low" before transmitting. This indicates that the ES80 is "busy".
Once the transmission and reception sequence ends, the ES80 sets the Ready To Send (RTS)
signal to a logic "high" to indicate that it is ready for the next ping.
Master mode
When the ES80 is "Master" in a system, the synchronization can either take place in Free
running mode, or in Wait for slave mode.
• Synchronization in Free running mode
When in Free running mode, the ES80 will ping as fast as possible, setting its Ready
to Send (RTS) signal to a logic "high" at start of each ping, and back to logic "low” at
the end of the ping. The "Slave" system is triggered the when the Ready to Send (RTS)
signal goes from "low" to "high".
• Synchronization in Wait for slave mode
When in Wait for slave mode, the ES80 will wait for a logic "high" Clear to Send (CTS)
signal from the "Slave" system before it starts a new ping sequence. This is the "ready to
ping" acknowledge from the "Slave" system.
Note
If you use the ES80 as "Master" to control two "Slave" systems, you must connect a single
cable (plus ground) from the Ready to Send (RTS) output on the Master system to the Clear
to Send (CTS) input on both "Slave" systems. The return from the Ready to Send (RTS)
outputs on the "Slave" systems can not be connected.
Cable layout and interconnections