Transas T214, Technical Manual

Page: 107 / 115

DGPS corrections input port
Chapter 8. Communication Protocol.
105
Digital Outputs status request:
Request: !EIAIQ,UNIT={1|2|3},DGOUT=?*CS<CR><LF>
Answer: !AIPWR,UNIT={1|2|3},DGOUT={0|1}*CS<CR><LF>
Digital Inputs status request:
Request: !EIAIQ,UNIT={1|2|3},DGINP=?*CS<CR><LF>
Answer: !AIPWR,UNIT={1|2|3}, DGINP={0|1}*CS<CR><LF>
9.4
DGPS CORRECTIONS INPUT PORT
The AIS Base Station has an interface to receive differential corrections. It is
assumed that the AIS Base Station receives differential corrections (in RTCM
format) via this interface with subsequent passing them to the AIS channels. Thus
the interface is only used in one direction.
The differential corrections are transmitted in a not-transparent mode. ITU-1371
standard requires geographical coordinates of the reference station to be transmitted
via AIS channels with every sent message. To meet this standard AIS station stores
coordinates of up to 4 reference stations. Differential corrections coming from reference
stations and not found in AIS station are ignored. Reference station coordinates can be
entered manually via control and display panel (during setup procedure) or they can be
calculated from Cartesian coordinates by station itself (some stations broadcast
Cartesian coordinates – see RTCM message 3). In any case, accuracy for transmitting
geographical coordinates is 0.1 minute of latitude and longitude.