Alcorn Mcbride V+ series, Руководство пользователя

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15-15 Appendix A
– Adding User-Defined Serial Protocols
Ap
p
end
ice
s
A
@complex . If the
completionack
field is not specified, the Show Controller
assumes there is no response after the event is completed.
If the messageack and completionack fields are both not specified, the
Show Controller assumes there is no response whatsoever from the device, and
it ignores both the
retries
and
timeout
fields. The message is simply sent out,
and that's it.
Multiple Variations of the Same Event
In many cases the same operation could take several different arguments. For
example, the
Search
event often has multiple variations, because many devices
support multiple ways of searching. On most DVDs, you can search to a
specific time or a specific frame number . Rather than make two different events,
like
SearchTime
and
SearchFrame
, it makes more sense to overlap the two
events. The following two events are an example of this:
[Search:Frame]
param1=port, "A valid Port"
param2=framestring, "A valid Frame number"
message="FR" @string(param2) "SE" h0d
retries=1
timeout=120
completionack="R" h0d
[Search:Time]
param1=port, "A valid Port"
param2=timestring, "A valid Time"
message="TM" @string(param2) "SE" h0d
retries=1
timeout=120
completionack="R" h0d
The compiler will attempt to compiler all variations of the same event before
giving an error. The first event that successfully validates all parameters is used.
Using the above two events, if a user enters a frame number as the second
parameter, the first event validates, and compilation continues. If the user enters
a time as the second parameter, the first event does not validate, but the second
one does, so compilation continues. If the user enters the Date as parameter 2,
both events do not validate, and compilation fails on this event.
Multiple variations can also be used when a event has optional parameters.
[Play:UntilFrame]
param1=port, "A valid Port"
param2=framestring, "A valid Frame number"
message="FR" @string(param2) "PL" h0D
retries=1
timeout=65534
completionack="R" h0d