The Simulavr project is a simulator for the Atmel AVR family of 8-bit, risc
microcontrollers. Currently supported devices include the at90s1200,
at90s2313, at90s4414 and at90s8515. The simulation of these devices is not
quite complete, but most of the useful functionality is present.

Support is also present for running the simulator as a remote target of
gdb-5.x. Since gdb does not currently support the AVR micros, a patch is
supplied with simulavr to provide that support with the hopes that the gdb
patch will eventually be integrated into the gdb source tree proper.

Texinfo based documentation has already been started, but needs much work done
in documenting the internals of the simulator in order to help new developers
learn how to add support for new devices as Atmel introduces them.

The Simulavr project is expected to progress in the following stages:

  1. Solidify support for running as a gdb remote target.
  2. Acheive 100% simulation of the existing supported devices.
  3. Design and implement a modular external periheral interface to allow
     simulation of peripherals such as LCD displays, ethernet ports, etc.
  4. Add support for all at90sXXXX series devices.
  5. Add support for atMegaXXX series devices.
  6. Add support for atTinyXXX series devices.
  7. ???

The project already exists and you can see it at
  http://savannah.gnu.org/projects/simulavr/