The SimulAVR program is a simulator for the Atmel AVR family of microcontrollers (ATtiny and ATmega). SimulAVR can be used either standalone or as a remote target for avr-gdb. There are interfaces for Python and Tcl. When used in gdbserver mode, the simulator is used as a back-end so that avr-gdb can be used as a source level debugger for AVR programs.
PicShell is a small IDE for the JALv2 language, used to program MicroChip's PIC microcontrollers. It has a built-in 14/16 bit PIC simulator. The simulator allows some user interaction, and contains some external devices like LED, LCD, UART terminals, and buttons for quick code testing. PicShell supports ASM and JAL level debugging. It provide a built-in editor with syntax highlighting, auto-completion, and a type-assist feature. It provides a mechanism to achieve unit testing.