APPENDIX
AP-21
ZDA - Time and date
$--ZDA,hhmmss.ss,xx,xx,xxxx,xx,xx*hh<CR><LF>
| | | | | | |
| | | | | | +--------- 7
| | | | | +----------- 6
| | | | +-------------- 5
| | | +------------------ 4
| | +---------------------- 3
| +------------------------- 2
+--------------------------------- 1
1. UTC
2. Day, 01 to 31 (UTC)
3. Month, 01 to 12 (UTC)
4. Year (UTC)
5. Local zone hours, 00h to +-13h
6. Local zone minutes, 00 to +59
as local hours
7. Checksum
$AIALR - Set alarm state
$AIALR,hhmmss.ss,xxx,A,A,c--c*hh<CR><LF>
| | | | | |
| | | | | +----------------- 6
| | | | +----------------- 5
| | | +-------------------- 4
| | +---------------------- 3
| +------------------------- 2
+--------------------------------- 1
1. Time of alarm condition change, UTC
2. Local alarm number (identifier)
3. Alarm condition (A=threshold exceeded, V=not exceeded)
4. Alarm’s acknowledge state, A=acknowledged V=unacknowledged
5. Alarm’s description text
6. Checksum
!AIVDM - VHF data-link message
!AIVDM,x,x,x,a,s--s,x*hh<CR><LF>
| | | | | | |
| | | | | | +----- 7
| | | | | +----- 6
| | | | +-------- 5
| | | +------------ 4
| | +-------------- 3
| +---------------- 2
+------------------ 1
1. Total number of sentences needed to transfer the message, 1 to 9
2. Message sentence number, 1 to 9
3. Sequential message identifier, 0 to 9
4. AIS channel Number
5. Encapsulated ITU-R M.1371 radio message*
6. Number of fill-bits, 0 to 5
7. Checksum
*= Message no. 1, 2, 3, 5, 6, 8, 12, 14, 18, 19 are used.
