Sony VPL-VW85 Projector User Manual


 
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VPL-VW85
3-3. Communication Procedure
3-3-1. Outline of Communication
All communication between CONTROLLER (PC, etc.) and DEVICE (PROJECTOR) is performed by the
command block format. Communication is started by the issue of a command at CONTROLLER and
ended when the return data is sent to CONTROLLER after DEVICE receives the command.
CONTROLLER is prohibited from sending several commands at one time. This means that after CON-
TROLLER sends one command, it cannot send other commands until DEVICE returns the return data.
DEVICE sends the return data after processing the command. The time from when CONTROLLER sends
the command until the return data is returned differs according to the contents of the command.
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When Sircs Direct Command is sent, return data may not be returned in some cases.
3-4. Communication Rules
. When sending a command from CONTROLLER, the return data from PROJECTOR should be re-
ceived first before sending the next command. Even if the next command is sent before receiving the
return data, since PROJECTOR will not be able to receive that command, it does not return a response
to CONTROLLER. Consequently, no error code is also sent.
For detail of the waiting times for PROJECTOR to return the return data after CONTROLLER sends
the command, refer to the section 3-5.
. When a communication error occurs, PROJECTOR ignores the data received until now, and set into the
reception standby state.
. For undefined commands or commends determined as invalid by PROJECTOR, PROJECTOR will
send the “NAK” return data to CONTROLLER .
. Take note that when data is written when the input signal of PROJECTOR is unstable, that data (value)
will not be incorporated.
. When INDEX specified SIRCS direct command is transmitted, leave an interval of 45 msec until the
next transmission. (Do not return the return data (ACK, NAK) when the SIRCS direct command is
received.)
3-5. Approximate Return Waiting Times
The await-return time is approx. 30 to 2700 msec.
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This is the case, unless the communications are interfered anyway.