GRASS VALLEY PERFORMER-HD, Instruction Manual

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Performer-HD Instruction Manual 3-11
Serial Protocol Descriptions
Command Strings
Commands,
<Data>
, must consist of exactly
<Len Hi> <Len Lo>
char-
acters forming a string of zero or more commands. Each command must
consist of a single
<CMD>
character identifying the command, followed by
any
<Data>
required by that command.
The following command characters and data are supported.
Except for the
S
command, all of the above are sent by the controller to the
Performer-HD. The
S
command is sent by Performer-HD to the controller
in response to a
Q
(Query for status) command. Performer-HD generates a
response to the
Q
command only.
The
R
command (Reset) causes Performer-HD to initialize just as if power
had been turned off, then on. No data should follow the
R
command.
The
D
command allows matrix crosspoints to be preset but not actually ac-
tivated. A subsequent
A
or
T
command causes preset values to take effect.
This can be useful when you wish to switch several switchers on a particu-
lar video field and thus have no time to send several messages. The
D
com-
mand is used to set up the switchers; then a series of short
A
commands to
each switcher initiates the switch.
The
A
and
T
commands both set all levels.
D
commands should be sent to
set the values of any level which are not to be the same as in the last
A
or
T
command (source 1 initially).
Table 3-3. Command Characters
<Cmd> <Data> Description
D (44H) <Sources> Data preset, source to destination
A (41H) (None) All-destination Take of current preset matrix
T (74H) <Dest> Take of specified destination only
P (50H) <Dest> Protect specified destination (must be refreshed every 30 seconds)
C(43H) <Dest> Clear protect on specified destination
R (52H) (None) Reset Performer-HD to factory defaults
Q (71H) <Dest> Query for status of specified destination
S (53H) <Status> Status response