Each data subscription requires an identifier to identify from which subscription the data is requested. ChannelID (channel identifier) is used for the frequency channel in normal echo sounder operations. A comma separated list of available identifiers can be obtained from the parameter TransceiverMgr/Channels. VirtualChannelID is the identifier during missions and ADCP velocity subscriptions. The VirtualChannelID comprises a ChannelID and a PingID. The Ping ID identifies specific pings in a ping sequence from a transducer. The virtual channel name is currently not fully supported by the subscription functionality. Therefore when making a subscription to a logical channel, data for the first defined virtual channel related to this particular
logical channel (transducer) is returned.
The data output always starts with a 64-bit integer time value. This value identifies the number of 100 nanoseconds intervals
that has elapsed since January 1, 1601.
The subscription input string is a comma separated list of input parameters. Numerical parameters must use "." (full stop) as decimal separator. If a parameter is skipped in the subscription input string it will be replaced by its default value.
In the output data to be received by external devices, the information about the current structure length is provided. From
this information, the number of elements in an array may be calculated.
NoteThe decoding of the subscription is case insensitive.