VICI SVI - Manual (Page 15)

11
Responses Received from the SVI
The SVI transmits responses to host commands or to perceived changes
in valve status. It also echoes commands which are not directed towards
itself. While the syntax of the response is identical to that of the transmitted
command, the content may differ. This permits differentiation of critical
responses from echoed commands.
The SVI responses are listed below:
RST This response always follows an SVI reset. The reset can be the
result of a power failure, or the receipt of the R command from the
host.
EON This is the SVI’s response to the identical command from the host.
It indicates that all commands to the SVI will generate a serial port
response.
EOF This is the SVI’s response to the identical command from the host.
It indicates the SVI will generate a serial port response only to
bad commands, or positioning commands to valves configured
for feedback which fail to indicate successful positioning.
BCMD This is the SVI’s response to host commands which are directed
to the device, but cannot be executed. An example might be a
numeric positional command sent to a 2 position valve, or a
positional command to a multiposition valve which exceeds its
set limit, etc.
S This letter represents a status response. It may be preceded by
the device ID depending on the Mode setting. It in turn always
precedes one of the following: (1) a valve number and the sensed
position, (2) an error indication (represented by the letter E) which
results from as invalid position sense, or (3) a motion indication
(represented by the letter M) which results from the sensing of the
run line asserted on the multiposition valves.
This response is initiated by a status request or a valve positioning
command (if the echo is enabled) from the host. If feedback is not
required, the response following a valve command will reflect the
attempted position rather than a sensed status.
L This letter represents a limit command response, and follows a limit
request or a limit set command. It may be preceded by a device ID,
but is always followed by a multiposition valve number (5 or 6) and
the last limit position set for that valve.
Remember, all the responses above may be preceded by the SVI ID
number.
Communicating with the SVI using Vcom