Trimble ThunderBolt E GPS Disciplined Clock User Guide 71
Trimble Standard Interface Protocol A
Command Packet 0x8E-A8: Set or Request Disciplining Parameters
This packet allows the user to change key disciplining parameters in the receiver. It is
usually intended to be used only when instructed by the factory. Incorrect use of this
packet will most likely cause timing outputs to be degraded severely. However, the
"Type 2" (Recovery Mode) parameters are intended to be set by the user to suit the
application. Send this packet with the type field only to request the current settings.
The receiver replies to sets and requests with the packet 0x8F A8.
Type Data field Description
0 Type A zero in this field indicates that the packet contains loop
dynamics information.
Time Constant This field carries the time constant of the disciplining control
loop
Damping Factor This field carries the damping of the disciplining control loop.
1 Type A "1" in this field indicates that the packet contains 10MHz
oscillator parameters.
EXCO Constant This field carries the OCXO constant into Hz/Volt.
The receiver determines this value automatically during a
calibration step run during the Power-Up mode following a reset
or power cycle. This value is therefore ignored by the
Thunderbolt E.
OCXO
Minimum
Control Voltage
This field carries the minimum (most negative) control voltage
that can be applied to the 10 MHz oscillator's control voltage
input.
OCXO
Maximum
Control Voltage
This field carries the maximum (most positive) control voltage
that can be applied to the 10 MHz oscillator's control voltage
input.