NZFS 15-15-8000 VisualPet User’s Manual
Iss: VPetNZFS 06/09
Sea Air & Land Communications Ltd.
Page 21 of 23
NZFS TNPP Packet Structure – NZFS Sky Only
Below is a description of the TNPP packet structure implement for NZFS:
The NZFS implementation has incorrect information in the data
block but is ignored by the decoder.
VP Router has TNPP Protocol for generation of genuine and
NZFS packets
TNPP Packet Format [ TNPP3.8 Page 23 ]
Field Name Number of bytes
SOH (start-of-header flag) 1
Header
12
STX (start-of-text flag)
1
Data block(s)(one or more) N
ETX (end of text flag)
1
CRC
2
[01]e004ee777749[02]FA00`01234567THIS IS A TEST PERIODIC PAGE SEQUENTIAL
NUMBER 9651 [03][8b][8e]
NZFS Packet Breakdown:
[01] = SOH Start of Header
e004 = destination address
ee = inertial value
7777 = source address
49 = incremental message ID
[02] = STX Start of Text
F = Extended CAP Page *** incorrect
A = APOC2400 *** incorrect
0 = *** incorrect not even defined
0 = RF Channel designator
' = RF Zone designator *** incorrect
0 = Function Code - see TNPP3.8 page 42
1234567 = Pager RIC or Cap Code - should be 8 chars
THIS IS A... = Message for Transmission
[03] = ETX End of Text
[8b][8e] = CRC error check
NB: There is a field missing in the RIC code - should have 8
Protocol Notes:
NZFS TNPP Packets sent across the Sky Network contains the source address of 7777.
NZFS TNPP Packets sent from VP Router to the 15-15-5000 contains the source address of 1234.
The 15-15-5000 controller therefore knows from which source the TNPP Packet has been sent. A
TNPP packet with the source address of 7777 means the 15-15-5000 will use the programmed RIC
Translations, any other address will result in the received RIC code being used by the 15-15-5000
transmitter.