Furuno FELCOM 12 Service Manual page 52

Communication between DCE (Data Circuit terminating Equipment)
and DTE (Data Terminal Equipment)
The two units are connected by a serial I/O, using hardware that conforms to RS-232C,
start-stop synchronization, and non-procedure protocol. Communications between
DCE and DTE are in a free flow. However, DCE checks commands sent from DTE
and returns its responses to DTE. For example, suppose that DTE sends a setup data to
DCE and asks DCE for its various relevant data. If DCE does not return its response
within 2 seconds, DTE resends the request command up to twice. Then, if DTE does
not yet receive any response from DCE, DTE asserts a warning ' No response from
communication unit ' and terminates the communication process.
Communication parameters
• Baud rate
• Data length
• Stop bit
• Parity
• Flow control line : No (using TX/RX data line)
Signals between DCE and DTE
No. Command from DTE to DCE
1 Changing EGC channel
2 Abort
3 Alarm stop
4 Finding TX message storage area
5 Login
6 Logout
7 Forced clear
8 Message transmission start
9 Distress alert
10 Start PV test start
11 TX channel
12 Message delivery confirmation request
13 Common channel assignment
14 NCS scan
15 Distress alert test
16 Response for repeating
17 Message transfer
18 Self-test start
19
: 4800
: 8 bits
: 1 bit
: ODD
Information from DCE to DTE
Network information
Current channel type
Rx message data
(LES, date, priority, size, etc)
EGC message
Login status
TDM Information
No. of RX message in DCE
BBER
Available memory size for RX message in
DCE
MES status
Current TDM type
NCS in use
PV test result
Message transmission result
Message delivery information
Request for repeating (distress alarm, distress
alarm test)
DCE information
(Status, position, Self-monitoring,
self-test result)
Alarm (Print, command response, etc.)
Polling data
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