Imagine NEO DVR-3901, Installation And Operation Manual

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46 DVR-3901 Installation and Operation Manual
Chapter 4: Remote Operation
Control Port Assignment
You can connect one RS-422 controller, via the serial port, and one or
multiple UDP controllers, via the ethernet port, to the DVR-3901.
However, the DVR-3901 can only respond to one controller at a time.
To prevent the DVR-3901 from receiving conflicting commands from
different controllers, the DVR-3901 uses the following rules to assign
control to a specific controller:
•
On power up, DVR communication is in an idle state.
• If there is no communication on an active control port for 15
seconds, that control port will become inactive, and communication
will go to an idle state.
• There are three ways to set an active control port:
•
If DVR communication is in an idle state, the DVR will grant
access to the first controller that sends commands to it, and
assign the corresponding control port to be the active control
port.
• To switch between an RS-422 port and a UDP port, set the
CtrlPort command in Pilot or use the card edge controls to
make that port active.
• From any port, a controller can set a new active port by sending
a
CtrlPort command (Please refer to the DVR-3901
Automation Control Developer’s Manual ).
A controller can perform one of the following options to obtain control
of the DVR:
•
Issue a get Ctrl_Port status command
The DVR will reply with 0 if the active port is RS-422 or the IP
address of the active UDP controller if the active port is UDP.
• Force a connection by sending the set CtrlPort command
Note
The NeoVR Command Center
automatically handles Control
Port switching using
Communication Settings and
with the
Connect/Disconnect
button on the VR View. Please
refer to the
NEO VR Command
CenterUser Manual for details.