GRASS VALLEY PERFORMER, Instruction Manual

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Serial Protocol Descriptions
Performer Remote, TEN–20/20-TEN Compatible Protocol
This protocol provides bidirectional communication between
controlling devices and crosspoint controllers on a single shielded
twisted-pair cable. RS485 standard is used, allowing a maximum
of 32 communicating devices on the bus. The protocol supports
crosspoint matrices up to 4 levels, each 99x99. When this protocol
is selected, Performer forces the serial port to 76.8K baud, 8 data
bits, no parity.
When selecting this protocol, note that four variations are allowed
depending upon the position of switch 2, segments 6 and 5. If 6 is
OPEN, each Performer level (video, audio 1, audio 2) is treated as
a separate level in the protocol (independently controllable within
the switcher). If 6 is CLOSED, all three levels are treated as a single
level and switch simultaneously. (A breakaway can still be
executed at the switcher integral control panel).
If segment 5 is OPEN, the switcher will be in master mode. In
master mode, Performer receives, executes, and responds to
commands. If segment 5 is CLOSED, the switcher will be in slave
mode. In slave mode, Performer receives and executes commands
but does not respond on the serial bus. Slave mode is used when
it is desirable to use multiple Performers assigned to the same
level and destination number. The switchers will execute
commands simultaneously but only a single Performer (set to
master mode) will respond with a tally message. Only one master
mode Performer may be on any one level/destination
combination at a time. Otherwise, garbled communications due to
bus collisions will result.
Source, Level, and Destination offsets which allow you to use
multiple master mode Performers on the same bus (but not the
same level and destination) are determined by Performer switch
S1. See the Installation section of this manual.