From: Michelle’s LabLDM #401: Boeing 747 digital fuel quantity indicator – teardown, reverse engineering and testIntroductionInterface Display
Label Information
Connector
Pinout of the Aviation ConnectorOpening the Instrument
From Altera’s CPLD, EPM7160 1MHz Crystal Oscillator
Power Board (LT1074)Reverse Engineering: Power Supply
Power SupplyReverse Engineering: Dimmer Circuits
0-5V, 400Hz AC Voltage Rectification Comparison 8-bit Sent to CPLDReverse Engineering: ARINC 429 Interface
Optocoupler (an ARINC 429 Interface Bus)
Corresponding Two-Line DisplayReverse Engineering: CPLD Circuit Board
Two CPLDs Receiving Signals and DisplayingTesting
Device
Power Supply +28V
Connected to Function Generator
Point Testing
Commands, LabelsDimmer Function Test Schematic Diagram:
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