Full family datasheet, 1.60 MB PDF, covering the tiny24, tiny44 and tiny84, consistent with the Atmel AVR ATtiny24/44/84 microcontrollers. These share a 14-pin layout and differ in flash, EEPROM and SRAM size. The document should include pin descriptions, clock and fuse options, peripherals, absolute maximum ratings and the programming interface. Technicians rely on it to wire an ISP programmer to the right pins, check supply voltage tolerances and understand how a board uses each I/O line when tracing a fault.
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.