Sea-Bird Electronics SBE 45 MicroTSG, User Manual, Page: 93 / 143

Appendix I: NMEA Data SBE 45 Interface Box
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Troubleshooting NMEA
Problem 1: Yellow NMEA LED Not Flashing
Cause/Solution 1 : Wiring may be incorrect. Check cables and connections
between the Interface Box, NMEA navigation device, and computer.
Cause/Solution 2 : NMEA navigation device may be set to the wrong
communication parameters (Interface Box requires 4800 or 9600 baud, 8 data
bits, 1 stop bit, and no parity). Reset device’s communication parameters.
Verify that the baud rate in the Interface Box for communication with the
NMEA navigation device is set to match (
NMEABaud= ), and that the baud
rate is less than the baud rate for communication between the Interface Box
and the computer.
Cause/Solution 3 : NMEA navigation device may not be transmitting data. See
the device manual for setup details. To verify that it is sending data, connect
an oscilloscope with ground on NMEA B (T17) and the probe on NMEA A
(T16). The signal should be less than 0.5 volts between messages and have
pulses greater than 4 volts for at least 0.2 milliseconds during the message.
Cause/Solution 4 : Interface Box may not be operating properly. To verify, use
the simulation program supplied with SEASOFT V2. This program simulates
a NMEA navigation device transmitting a NMEA message. See
NMEA
Message Simulation Program for details.
Problem 2: Yellow NMEA LED Flashing, but Lat/Lon Data
Not Displaying
Cause/Solution 1 : NMEA navigation device may be transmitting NMEA
messages in a format that cannot be interpreted by the Interface Box. To
verify, view the raw NMEA messages:
1.
With the Interface Box running in Normal mode, type ConnectNMEA
and press the Enter key to switch to NMEA mode. The display looks
like this:
Decode NMEA messages, press @ or Esc to return to normal mode
2. The raw NMEA data should begin scrolling on the screen, followed by
the decoded data. A typical RMC NMEA message is:
NMEA: $LGRMC,123113.21,A,3625.12,N,12121.34,W,1.2,4.5,231294,1.2,a*45<CR><LF>
Decoded: , lat=36 25.12 N, lon=121 21.34 W, hms=123113, dmy=231294
See
NMEA Raw Message Formats for a description of all the NMEA
messages the Interface Box can decode.
•
If a different NMEA message is received than the Interface Box is
set up to decode
, reconfigure your NMEA navigation device to
transmit GGA, GLL, RMA, RMC, or TRF.
•
If no NMEA messages are received in NMEA mode , the problem
could be in the Interface Box, cable, or NMEA navigation device.
Verify that the Interface Box is operating properly using the
simulation program supplied with SEASOFT V2. This program
simulates a NMEA navigation device transmitting a NMEA message.
See
NMEA Message Simulation Program for details.
3. Type @ to return to Normal mode.
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