Grass Valley 2200 - Manual (Page 15)

2-1
Serial Communications
This section describes the communications protocol and its error handling.
A Video Editing System uses the switcher editor port to exercise real-time control
over the switcher's functions. The editor is really an external computer that can
input and output functions. Such functions select crosspoints, perform auto
transitions, or perform E-MEM (Effects Memory) register recalls, to name just a
few possibilities. Refer to the appropriate switcher Operation manual for
deÞnitions and explanations of the switcher functions and features.
Editor Protocol Access
The 2200/3000/4000 Editor Protocol is based upon, but not identical to, the
proposed SMPTE (Society of Motion Picture and Television Engineers) Digital
Control Interface, which establishes a means for the orderly ßow of data over a
serial bus.
The major components of the protocol are shown in Figure 2-1 and discussed in
the following paragraphs.
Figure 2-1. Components of the Model 2200/3000/4000 Editor Protocol Access
Break
Character
Address
Byte
Command/Message Blocks
0350-06
Editor Protocol
2