Large 10.5 MB PDF datasheet identified only by document number 6175, with no part name in the file title. A much smaller 1.22 MB file with the same number and an s suffix also exists in this collection, so this one is probably the complete edition with full register descriptions, electrical characteristics and package data. Open it in a PDF reader and confirm the part on the cover. Technicians use such full documents for detailed pin functions, programming interfaces and timing when diagnosing a 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. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.