Yesterday I got an idea to write an application that could emulate the whole instruction set of the 68HC11 CPU with all the memory and external devices attached to it. It would be something like an ECM test bench just running on a PC instead of having it physically on my desk.

I found this idea useful for myself because it would make debugging of unknown ECM binaries a bit more easy instead of just looking through the assembly code and trying to understand everything.

The other advantage is that it would be possible to try out binary modifications without having a complete ECM test bench or going out to the garage and uploading the new binary to the car every time.

I checked google for such kind of tool but found almost nothing. There was a tool that could emulate this particular CPU but it is not a free application and not even designed for this specific use to simulate ECM software.

What do you think?

 

I've looked for an simulator to run 'HC11 code on a PC. I found SIM68 but never played with it too much. Part of the issue is that a simulator doesn't simulate the ECM hardware. And, the GM ECMs don't run an off the shelf 68HC11.

What would be a decent simulator would be to also include ECM hardware pieces (in software). And have the emulator decipher and display what the hardware is doing. Such as converting the counter values to actual injector PW, dwell, and timing.

And be able to change inputs such as the CTS, IAT, MAP and so on.

That would be a virtual ECM bench and be very useful.

RBob.

 

That is exactly what I am planning to do.

 

I purchased Thrsim for $50 a few years ago.
Helped with stepping through some code sections.
Biggest problem was the simulator had different syntax requirements than my assembler so I had to keep altering code to do things.
I'd still like to have something that worked well for what we do.

http://www.xs4all.nl/~hc11/thrsim11/thrsim11.htm
The editor that comes with it is nice to work with as well.