Newport New Focus Picomotor 8743-CL, User Manual

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6.1.1 RS-485 Command Syntax
The command syntax for communicating with controllers on an RS-485 network is very
similar to communicating with them directly using USB/Ethernet interface with the
following exceptions:
1. All the commands intended for a slave controller must have a slave controller
address prefix added to the command. For example, to query the motion status
of motor 2 on a slave controller with address 3, the host PC must send
“3>2MD?” command to the master controller. In this command, “3>” is the
slave controller address prefix. This prefix tells the master controller that the
command “2MD?” is intended for slave controller with address 3.
2. When the master controller sends a response back to host PC, it too will have a
slave controller address prefix. This is used to inform the host that the
response came from a slave controller with that address. For example, the
response received by a host PC to the above mentioned command might be
“3>1”. This indicates that the motion of motor #2 in slave controller with
address 3 is complete.
3. If a command does not have controller address prefix, the master controller will
assume that the command is addressed it and process the same.
4. Since the master controller processes one command string at a time, semicolon
(‘;’) delimited commands cannot be sent to slave controllers.
NOTE
A controller command (or a sequence of commands) has to be terminated with a
carriage return character. However, responses from the controller are always
terminated by a carriage return/line feed combination. This setting may not be
changed.