Kongsberg Simrad EK80, Руководство по установке

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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 EK80 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 EK80 is set up in Slave mode, it must receive a trigger signal from a peripheral
system every time the EK80 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
EK80 an "event" message. The message is processed by the EK80 software, and it will
(if the previous ping has been finished) start the ping sequence.
As an acknowledgement to the synchronization trigger, the EK80 sets the Ready To Send
(RTS) signal to a logic "low" before transmitting. This indicates that the EK80 is "busy".
Once the transmission and reception sequence ends, the EK80 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 EK80 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 EK80 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 EK80 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 EK80 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.
Related topics
Setting up the EK80 in a synchronized system, page 126
Cable layout and interconnections, page 85
Simrad EK80 Installation Manual