Grass Valley Performer SD - Manual (Page 170)

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Section 3 — Operation & Service
SMPTE 3245-E Protocol
Performer may be controlled by a host computer using SMPTE
3245-E protocol if the proper switches on the Performer have been
set. The SMPTE 3245-E protocol is based on the following SMPTE
standards documents:
■ Remote Control Systems for Television Production
Equipment, Tech 3245-E,
December 1984.
■ Remote Control Systems for Broadcasting Production
Equipment: System Service and Common Messages,
Supplement 1 to Tech 3245-E,
June 1986.
■ Remote Control System for Broadcasting Equipment,
Routing Switcher Type-Specific Messages
, Draft 0.1, July
1988.
Performer has NO non-standard communication sequences used
with the SMPTE ESCAPE sequence. If Performer is selected and
the SMPTE ESCAPE character received, Performer will enter the
IDLE state and call protocol error.
On reset, Performer assigns itself to the SMPTE all-call group
address and clears all other group assignments.
Performer does not make entries in the bus controller linkage
directory. This must be handled by another device on the bus.
Performer is a single virtual machine. Messages for selecting
virtual machine are NOT supported.
SMPTE standard (1984) shows the receive values for the ASSIGN
state to be 00-0F, 80-FF. This appears to be an error. It is 00-7F for
deassignment and 80-FF for assignment.
SMPTE BUSY status (06H) is never returned by Performer.
Protocol error is called when a protocol error occurs. Receive error
is called when a message we send is NAK’d by the bus controller
or when a message with a bad checksum is received.
SMPTE messages implemented by Performer are listed in
Table 3-2. SMPTE information fields implemented by Performer
are listed in Table 3-3.