1756HP-GPS - User Manual Rev 2.8
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The current status of the module is conveyed to the user by means of the 3 bi-color Status
LED’s and the alphanumeric LED display.
The following information is available to the user directly across the backplane by means
of a scheduled connection:
•Date and Time in Gregorian Format (year, month, day, hour, minute etc.)
•Universal Coordinate Time (UTC)
•GPS Receiver Status
•Number of satellites being tracking
•Position in Polar Coordinates (latitude, longitude and altitude)
•Position in Cartesian Coordinates ( Earth-centered-earth-fixed X,Y,Z axis)
•Velocity in Polar Coordinates (Northerly, Easterly and Upward)
•Velocity in Cartesian Coordinates ( Earth-centered-earth-fixed X,Y,Z axis)
The module requires regular updates of the ControlLogix Controller’s CST (Coordinate
System Time) value to enable accurate CST conversion and wall-clock offset functions.
All time and date information can be adjusted to the local time-zone by configuring the
Time-Zone offset, in the scheduled output image.
Detailed GPS satellite information can also be requested by means of an unconnected
message, responding with the following for each of the 8 GPS receiver channels :
•Satellite Identifier (PRN)
•Current Satellite Azimuth
•Current Satellite Elevation
•Signal Strength
The 1756HP-GPS module supports two unconnected time conversion services, namely:
•CST ÆUTC and Gregorian
•UTC ÆGregorian
This allows the user by means of a custom message service to convert between different
time formats. The conversion is valid only for time data that is less than 1 hour old.
