NavCom Sapphire Rev.J - Manual (Page 179)

Sapphire Technical Reference Manual Rev. J
179
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An example of data that would likely be scheduled ONCHANGE is GPS satellite
ephemeris data. Ephemeris data normally change every two hours but are received
from the satellites every 30 seconds.
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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.”
Table 74: Output Command Port Mnemonics
Keyword Mnemonic Data Port
1 RS232 Serial port 1 (COM1)
2 RS232/RS422 Serial port 2 (COM2)
3 Sapphire board only
4 Sapphire board only
5 RS232 serial port 5 (Sapphire)
6 RS232 serial port 6 (Sapphire)
BT Bluetooth
USB1 USB port 1
USB2 USB port 2 (not yet available)
FH1 Internal 2GB SD flash memory
FH2 USB flash drive 2 (SF-3050)
ETH1 Ethernet port 1 (SF-3050)
ETH2 Ethernet port 2 (SF-3050)
ETH3 Ethernet port 3 (SF-3050)
ETH4 Ethernet port 4 (SF-3050)
RADIO PIO radio port (SF-3040)
Examples: [OUTPUT] PVT1B,ONTIME,1,1
Outputs PVT1B messages every second on port 1
[OUTPUT] PVT1B,,2,1
Command rejected. Timing argument is required when interval is set