Sony VPL-EW130, Руководство по протоколу

Страница: 12 / 38

8
VPL-EW130
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.
n
When SIRCS direct command is sent, return data is not sent.
3-4. Communication Rules
.
When sending a command from CONTROLLER, the return data from PROJECTOR should be received
fi rst 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 unde fi ned commands or commands determined as invalid by PROJECTOR, PROJECTOR will
send the “NAK” as return data to CONTROLLER .
.
Take note that when data is written with the unstable input signal of PROJECTOR, that data (value) will
not be incorporated.
.
When INDEX speci fi ed 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.)
.
For POWER ON/OFF/TOGGLE of the SIRCS direct command, send the command twice when this
unit is in standby mode (Low) state.
3-5. Approximate Return Waiting Times
The await-return time is approx. 30 to 1000 msec.
n
This is the case, unless the communications are interfered anyway.