NavCom Sapphire Rev.J - Manual (Page 177)

Sapphire Technical Reference Manual Rev. J
177
1.125 OUTPUT (ASCII)
SF-3050 Sapphire SF-3040
This command is used to control which data the Sapphire engine outputs on its data ports. The
Sapphire engine output data are organized into different types of output messages, also called
output streams. Section 2 discusses the Sapphire Output Messages and provides detailed
descriptions of their formats. Each Sapphire output stream or message is identified by a unique
mnemonic. The [OUTPUT] command uses these mnemonics, and other optional arguments, to
set up and control the output scheduling for the different output streams.
Command: [OUTPUT] mnemonic, {timing}, {interval}, {port}, {keyword}
Parameter Definition
mnemonic
Keyword that identifies the name of the output stream to be scheduled. If the keyword
“NONE” is used for this argument, all outputs are turned off on the specified port, including
the [OK] and [??] outputs used to acknowledge or reject input commands.
timing Keyword that identifies scheduling or timing method (see Table 73)
interval
1
Time interval between outputs, truncated to the nearest 0.01 second (float, seconds)
(0.01 to 9999.9)
port
Keyword that identifies the data port to use for the output stream, or - 1 to mean “all ports”
(see Table 74).

If ONTIME is selected, and the interval specified is finer than the rate at
which the data contained in the message are updated, then the message
output interval will average out to the specified interval rather than occurring
exactly at the specified interval. For example, if the navigation computation
rate is set to 10 Hz, but the PVT1B message is scheduled to be output
ONTIME every 5.12 seconds, then the interval between consecutive PVT1B
messages will dither between 5.10 seconds and 5.20 seconds, averaging out
to 5.12 seconds.

An example of data that would likely be scheduled ONCHANGE is GPS
satellite ephermis data. Ephemeris data normally change every two hours,
but are received from the satellites every 30 seconds.

EPHEM1B is a special case message. It can be output for the entire list of
satellites (tracked or not) or specified for a specific satellite. These two
special cases are typically used at base station startup or hub software
startup in a network solution. The ability to poll the receiver for a specific
PRN’s ephemeris allows the network to easily recover from data outages that
might occur on an Ethernet link, for example. The third (and normal usage)
case is to schedule EPHEM1B
“Onchange.” In this mode, the receiver
unpacks and passes on satellite ephemerides as they are received from the
satellite (the normal, ongoing operational condition).
When incorporated into an end-user program, do not poll the receiver
for the complete EPHEM1B list more than once every 60 seconds.

End-user programs can request the entire EPHEM1B LIST “Once” and
immediately follow this command with “Onchange.” Record all of the settings
before using -1 as the port number (see caution note, below).
keyword
Extra keyword; meaning depends on the mnemonic. If the keyword is defined for the
mnemonic, it is accepted as an input and included in the query response.