Advanced Configuration And Control - AMX Modula Instruction Manual

RS-422 Boards

Advanced Configuration and Control

This section covers the advanced configuration routing of X to Y Fanout and the commands for
executing it.
Note: If you need to change the system's configuration, see page 146.
The order in which the signals are routed is important because in one-to-many routing, only the last
device status signal that is returned remains connected.
Control Panels
Control Panels can be used to operate an RS-422 system configured for X to Y Fanout. Use the Change
command sequence for the control panel (see the control panel's documentation). When entering the
command, for an X-Port select Input (or Source depending on the control panel) and for a Y-Port select
Output (or Destination). Depending on the control panel, you may need to specify the Input first in the
Change command.
BCS Commands
BCS commands can be used for operating an RS-422 system that has been configured for X to Y Fanout.
When entering switch commands, for the X-Port use an I command character (normally thought of as
"Input") and for the Y-Port use an O ("Output"). It does not matter whether the "I"s or the "O"s are
specified first in the execute switch command. For information on BCS command characters and
command line formats, see the Instruction Manual – BCS Basic Control Structure Protocol on the
AMX AutoPatch CD or at www.amx.com.
X to Y Fanout
Using a single command, this configuration routes a controller signal from an X-Port to multiple Y-Ports
(the fanout part of the switch) and then automatically returns the last device status signal from the Y-Port
back to the X-Port. During the process (see the example in FIG. 101), the first device status signals
returned are immediately disconnected as each subsequent controller signal is routed (although the
controller signals remain routed). Only the last device status signal connected is left (the point-to-point
part of the switch). The process occurs so quickly that it seems as though only the one device status
signal has been returned.
FIG. 101
X to Y Fanout configuration
Control Panels
For the example in FIG. 101, enter a Change command that routes Input (X-Port) 2 to Outputs (Y-Ports)
1, 3, and 4. The last device status signal returned (from Y-Port 4) is the only status device signal that
remains connected. Since some control panels do not preserve the order of the ports entered, the device
status signal from the Y-Port that you want to remain may need to be sent separately for it to be other
than the last one in the numerical order. For example, when routing X-Port 2 to Y-Ports 1, 3, and 4, you
might want to have the device status signal return from Y-Port 1. To do so, you may need to enter the
command to route to Y-Ports 3 and 4 first, and then enter the command for Y-Port 1.
144 Modula Instruction Manual