This program not only Atmel microcontroller supports, but other manufacturers as well. Select the type you prefer: Project-> Options menu at the Default CPU. If the type is not listed, you can create your own as well.

There are thousands of different microcontroller, of course, I do not know all of them emulate. But for now this is not the goal of the program. The 8051 and 8052 basic functions are properly emulated, such as timers, interrupts, serial ports, ports, and its instruction set. The program is truly a real-time emulation of these things. I think, that a lot of programmers it is enough.