Datasheet for the SN74LS682, an 8-bit magnitude comparator from the low-power Schottky 74LS family. The rev7 in the name refers to the seventh document revision. The 77.0 KB PDF should include the pin assignment, logic diagram and electrical characteristics. ISA cards and other vintage boards often use this comparator to match an address against a jumper-selected value. Use the sheet to probe the P and Q input buses and the comparison outputs, and verify the jumper settings before you suspect the chip.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @datasheet_technar_org. Enginerys does not host this file.
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