High Quality Content by WIKIPEDIA articles! TilEm is an emulator that simulates certain Texas Instruments calculators on a generic computer. It is similar to TiEmu, uses GtK, and works on many different operating systems like Linux/Unix, FreeBSD, 32-bit Microsoft Windows and so on. If you have a copy of the information in the ROM from one of the ZiLOG Z80 series Texas Instruments Graphing Calculators (TI-83 series, TI-84 Plus series, TI-82, TI-85, etc.), with the exception of the TI-81, TilEm will emulate the behavior of the calculator without requiring the actual calculator hardware.