Trimble Outdoors thunderbolt 64057-00-eng Manuale Utente
Trimble ThunderBolt E GPS Disciplined Clock User Guide
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Setting up and Running the ThunderBolt E
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If the host has not uploaded a reference position, or if the module has been moved
more than one to two kilometers since its last position, the GPS module automatically
conducts a position survey at startup. By default, the GPS module averages 2000
position fixes before entering the clock-only mode. The host system can adjust the
survey period using packet 0x8E-A6. While the GPS module is performing its survey,
the accuracy of the timing outputs will be degraded.
more than one to two kilometers since its last position, the GPS module automatically
conducts a position survey at startup. By default, the GPS module averages 2000
position fixes before entering the clock-only mode. The host system can adjust the
survey period using packet 0x8E-A6. While the GPS module is performing its survey,
the accuracy of the timing outputs will be degraded.
Uploading a reference position
To upload an accurate reference position, use packet 0x31 (
reference position is stored in EEPROM (Electrically Erasable Programmable Read-
Only Memory) and is retained during power loss. When a reference position is stored
in EEPROM, the GPS module bypasses the position survey procedure and enters
clock-only mode. If you move the antenna, you must send packet 0x8E-45 to clear the
position stored in EEPROM: The GPS module then initiates a self-survey, unless the
host uploads a new position using packet 0x31 or packet 0x32.
Only Memory) and is retained during power loss. When a reference position is stored
in EEPROM, the GPS module bypasses the position survey procedure and enters
clock-only mode. If you move the antenna, you must send packet 0x8E-45 to clear the
position stored in EEPROM: The GPS module then initiates a self-survey, unless the
host uploads a new position using packet 0x31 or packet 0x32.
To store the reference position from the self-survey procedure in the EEPROM, send
packet 0x8E-4C to the receiver. Alternatively, you can configure the ThunderBolt E to
automatically save the position using packet 0x8E-A9.
packet 0x8E-4C to the receiver. Alternatively, you can configure the ThunderBolt E to
automatically save the position using packet 0x8E-A9.