Table 40: Message 55 - User Time Recovery - Applanix POS MV V5 Installation And Operation Manual

format which provides the time of the next 1PPS signal. PPS time is available from POS in either a NMEA
message (ZDA or PPS) or Binary output message (PPS or TM1B). Refer to COM Ports starting on page
3-1 for message format details.
Synchronizing POS to External Equipment
POS maintains a User time offset in addition to the GPS and UTC offsets with respect to its internal POS
time. This provides the user with the option of supplying POS with an external time message that will be
used to set the User time offset. Once set, the User time can be used as a time tag for ICD output data
groups.
To synchronize POS with external equipment time (User Time), the external equipment must read and
record the 1PPS signal from POS and transmit its User Time to POS on the Ethernet port. Refer to the
description of the Ethernet Connector on page 2-21.
'Message 55 - User Time Recovery' (Table 40) is extracted from Applanix document PUBS-ICD-004089.
This message specifies the time of the last PPS in User Time to the POS. It directs POS to synchronize
its User Time with the time specified in the User PPS Time field. POS accepts this message at any time
at a maximum rate of once per second.
To establish User Time synchronization, the user must send the User Time of last PPS to POS with this
message after the PPS has occurred. The resolution of time synchronization is one microsecond.
Message start
Message ID
Byte count
Transaction
number
User PPS time
User Time
conversion
factor
Pad
Checksum
Message end
This message must be sent by a user application that connects to the POS TCP/IP socket interface
(Control Port) to accommodate both the User Timing input and the substitute controller communication.
Copyright © Applanix Corporation, 2017
POS MV V5 Installation and Operation Guide

Table 40: Message 55 - User Time Recovery

Item Bytes Format
4 Char
2 Ushort
2 Ushort
2 Ushort
8 Double
8 Double
2 Short
2 Ushort
2 Char
Value
$MSG
55
24
Input: Transaction
number
Output: [65533, 65535]
[0, ) default = 0.0
[0, ) default = 1.0
0
N/A
$#
POS-GPS
Timing
Units
N/A
N/A
N/A
N/A
seconds
/seconds
N/A
N/A
N/A
H-5