Question

I would like to create/start a simulator for the following microcontroller board: http://www.sparkfun.com/commerce/product_info.php?products_id=707#

The firmware is written in assembly so I’m looking for some pointers on how one would go about simulating the inputs that the hardware would receive and then the simulator would respond to the outputs from the firmware. (which would also require running the firmware in the simulated environment).

Any pointers on how to start?

Thanks Chris

Answer 1

Writing a whole emulator is going to be a real challenge. I’ve attempted to write an ARM emulator before, and let me tell you, it’s not a small project. You’re going to either have to emulate the entire CPU core, or find one that’s already written.

You’ll also need to figure out how all the IO works. There may be docs from sparkfun about that board, but you’ll need to write a memory manager if it uses MMIO, etc.

The concept of an emulator isn’t that far away from an interpreter, really. You need to interpret the firmware code, and basically follow along with the instructions.

I would recommend a good interactive debugger instead of tackling an emulator. The chances of destroying the hardware is low, but really, would you rather buy a new board or spend 9 months writing something that won’t implement the entire system?

It’s likely that the PIC 18F2520 already has an emulator core written for it, but you’ll need to delve into all the hardware specs to see how all the IO is mapped still. If you’re feeling up to it, it would be a good project, but I would consider just using a remote debugger instead.