MCUSim - Microcontroller-based circuit simulator
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Readme for MCUSim

 MCUSim is a digital simulator of the 8-bit AVR microcontrollers. It is
 written from scratch to assist in circuit simulation, firmware debugging,
 testing, and signal tracing.

 Simulator can be extended by creating models written in Lua. They may affect
 state of a simulated MCU in several ways, e.g. access internal registers,
 generate signals on its pins or terminate the whole simulation, and play
 roles of the significant parts of a circuit connected to the microcontroller
 (external EEPROM, humidity sensor, MOSFET switch).

 There is an interactive script also to prepare a simulated MCU instance
 which is installed together with the simulator executable. It is particularly
 helpful to set up microcontroller for a firmware debugging (via remote GDB
 target at localhost:12750) or create a firmware test with Lua models to check
 conditions and parameters.

 Registers of a simulated MCU can be saved into a VCD (value change dump)
 file and read using GTKWave viewer.

How can I start a discussion?

 Feel free to ask questions and start a discussion in the mailing lists for
 users or developers. There are no specific rules which one to choose, so
 subscribe and send a letter.

How can I join the development?

 To join the development just code the feature you want to add and send
 your patch to the mailing list. Before you start coding check the latest
 development release of MCUSim from our git repository or try to find a
 ticket at It might be that your feature has
 already been implemented.

 There is no bureaucracy here.

Mailing lists

 There are three mailing lists dedicated to the announces, use and development
 of MCUSim.

   MCUSim announces. Subscribe to stay informed about new versions,
   release notes, etc.

   This is a list for the users of the MCUSim simulator.

   This is a list for developers and "want to be" developers. Subscribe to
   discuss any development issues and share patches.

 To subscribe the list(s), send a message to:

 To unsubscribe from the list(s), send a message to:

Web sites

 This project is hosted on
 Home page, wiki and issue tracker is at