CM170407AMA
FIG 12 THE ENCODING ALTIMETER TEST SCREEN
The “Gray code” label shows the 24 signals coming from the encoding device. The “Enc.”
label shows the decoded value.
The ADTS will also signal the change of the reading from the encoding device:
•
an acoustic sound will warn the Operator at every altitude transition point;
•
the Gray code and the decoded altitude will flash in green if the new value is
correct, or in red if the new value is incorrect. All errors are recorded.
The green button
View
shows the results of the current test in the Encoding Altimeter
Results Screen (FIG 13). The yellow button End shows the results and ends the test,
returning the MPS49 to the Status Screen.
The orange button Tst/Pw switches between the standard display (FIG 12) and an alternate
display, in which the yellow and green button control the power supply to the encoder and
vibrator of the connected altimeter.
FIG 13 THE ENCODING ALTIMETER RESULTS SCREEN
The Encoding Altimeter Test records the following kinds of errors:
•
Invalid Gray code: when the Gray code does not correspond to any altitude value,
and cannot be decoded. This error is marked as “Invalid”.
•
Direction error: when the encoded altitude increases while the simulated altitude is
decreasing, or vice-versa. This error is marked as “Direction”.
•
Skip error: when the encoding altimeter skips one or more values (for instance,
switching from 1,000 to 1,200 feet). This error is marked as “Skip”.
7.6 ARINC 429 CONNECTION (OPTION)
The optional ARINC 429 connectors on the front panel allow the MPS49 to receive data
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