Garmin GPS 400 Pilot's Manual & Reference page 210

SECTION 10
ADDITIONAL FEATURES
Monitoring the Data Link
The Data Link Status Page provides an indication of
the integrity of the Data Link. The Data Link Page allows
the pilot to monitor the system and determine the possible
cause of a failure.
View the Data Link Status Page:
1) From the AUX Page Group, select the Data Link
Page.
2) Highlight 'Data Link Status' and press the ENT
Key.
3) The Data Link Status Page (Figure 10-47) is
displayed.
Figure 10-47 Data Link Status Page
The GDL 49 Datalink Status Page shows the following
fields:
• TX Queue - Shows the number of requests in the
GDL 49' s transmit queue waiting to be sent to the
satellite.
• RX Queue - Shows the number of responses in the
GDL 49' s receive queue waiting to be sent to the
GPS 400.
• Sat ID/Connectivity - Shows the current satellite
in view and also indicates the status of the current
satellite connection. See Table 10-8.
10-32
MESSAGE
'_ _ _'
'Data Link has
failed'
'Linked to sat'
'Satellite in view'
'Searching...'
• SATCOM Operation - This field indicates the
current activity being performed by the satellite
communicator within the GDL 49. Table 10-9
lists the messages that can be displayed, including
interpretations of the most common ones:
MESSAGE
'_ _ _'
'Idle'
'Receiving
message'
'Sending message' Transmitting a message.
'Sending request'
• SATCOM SER NUM - This field shows the serial
number assigned to the GDL 49' s internal satellite
communicator.
• GDL SW - This field shows the currently installed
software version for the GDL 49.
GPS 400 Pilot's Guide and Reference
SAT ID/CONNECTIVITY FIELD
DESCRIPTION
RS-232 communication with the GDL
49 has been lost.
There is a disconnect inside the GDL
49.
Can exchange data with the satellite.
Found satellite but have not yet
identified it.
No satellite is currently in view.
Table 10-8 Sat ID/Connectivity Field
SATCOM OPERATION FIELD
DESCRIPTION
Unknown task is being performed,
or RS-232 communication with the
GDL 49 has been lost.
Waiting to perform the next task.
Receiving a response from the
satellite.
Transmitting a request to the
satellite.
Table 10-9 SATCOM Operation Field
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