Eurotech 930150-4003R, User Manual

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ZyWAN-G9 - User Manual
86 110150-4002A
When
Enable Cache? is set to No (Arcom format only), a UDP
acknowledgement is not required. The ZyWAN-G9 simply sends out the
GPS points when it can and does not store them locally. If the host
computer does not receive the position message, those positions are lost.
Arcom Format for GPS Messages (UDP)
When using the Arcom Format for GPS data, the position message is transmitted using the User
Datagram Protocol (UDP). If caching is enabled, the ZyWAN-G9 waits a minimum of 10 seconds to
receive an acknowledgement message after transmission of a position message. If a response
message is received that does not contain the characters
ACK or no message is received within the
timeout period, the position message is retransmitted. This process continues indefinitely. The ACK
must be 3 ASCII characters (0x41 0x43 0x4B).
The position message is defined next. The first 12 bytes are a header, followed by 19-byte portions
containing the timestamp and position information. The number of these 19-byte portions is
determined by the
Send Threshold parameter. All data is in binary big-endian format, unless otherwise
specified.
Message header:
som(1) snum(10) npos(1)
Position data (repeated):
sval(1) time(4) stat(1) sats(1) lat(4) lon(4) psrc(1) speed(1) head(2)