Download System Hardware Principles

System Hardware Principles
FIGURE A-7:
EXTERNAL TOOL ECL SYSTEM TEST BLOCK DIAGRAM
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The external test tool initiates an ECL system test as shown in Figure A-8.
The external test tool collects the following during the Results sequence.
TABLE A-1:
ECU
ECU SYSTEM TEST RESULTS
En Results
Node Class
Head Unit
On Results
1
0
HU alive
1
Did not detect stable lock
AuxIn
2
0
AuxIn alive
1
Did not detect stable lock
Amplifier
3
0
Amp alive
1
Did not detect stable lock
The first device in the ring, the AuxIn, did not detect stable lock indicating a
problem exists between the AuxIn network receiver and the previous device’s
transmitter. The test tool results indicate where the technician should look for the
problem. Once that problem is resolved, the technician should rerun the test to
determine if there are any other faults that might have been masked by the
problem before the AuxIn (double faults).
 2013 Microchip Technology Inc.
DS20005241A-page 33