Dolby
®
Model CP650 Installation Manual
External Control of CP650
E-6
Note
: All remotes must parse all messages. This requires looking at the length and
cannot be ignored.
To command the CP650 to toggle the mute setting, the data message must have a
value of zero. If the CP650 was unmuted before receiving this command, it will be in
the muted mode afterwards, and if muted before, it will be unmuted after.
The CP650 front-panel buttons can be thought of as being numbered 1 through 8
(format 01, 04, 05, 10, 11, U1, U2, and NS, respectively). To command the CP650 to
assert a format change, the data byte should be a number between 1 to 8.
To change the fader level, the data byte should be a value between 10 and 110. This
corresponds to a fader setting between 0.0 and 10. (Subtract 10 from the value of the
data byte, and then divide by 10 to obtain the resulting fader value.)
CP650-to-Remote Accessories Message
The message from the CP650 to any remote accessory will always contain two bytes
of data. The CP650 will periodically transmit this message to all registered remote
accessories to ensure that they have the proper data. This data message will also be
sent immediately whenever there is a relevant change in the state of the CP650.
The least significant seven bits of the first byte in the data packet (received from the
CP650) contains the current fader level, between 0 and 100. Divide by ten to obtain
the correct fader level.
The most significant bit of the first byte in the data packet tells the remote accessory
whether or not to blank its fader display (0 = display on, 1 = display off).
The least significant three bits of the second byte in the data packet contain the
current format of the CP650. The value will be between 1 and 8, corresponding to the
front-panel buttons as described above.
The next most significant bit tells whether the CP650 is muted (0 = not muted, 1 =
muted).
The next most significant bit tells which projector is in use (0 = projector 1, 1 =
projector 2).
The next most significant bit tells whether the current CP650 format is valid (0 =
normal, 1 = invalid format).
The next most significant bit tells whether the auditorium fader is active (0 = not
active, 1 = active).
The most significant bit of the second data byte is not used.