Re: [Simulavr-devel] Whats to do on execution of "illegal instruction"

[Klaus]

Am 06.02.2016 um 17:31 schrieb Michael Hennebry:
> It seems to me that the way to handle a specific invalid instruction,
> 0xFFFF or anything else, is to add it to the instruction set.
> If desired, startup code can read a configuration file.
Yes, implement all the options we discussed today ends up in configuring 
the simulavr with an additional config file. But this also opens a door 
to make the instruction set specific to the core itself. Some 
instructions are not valid on all cpu cores.

My idea is quite different from all that:

simulavr is a tool from programmers for programmers. If someone need for 
a debug session a different handling of an opcode, it is quite simple to 
implement the behavior in three lines of c code. I have no idea how 
flexible a config file should be. This ends in writing a simulator 
configuration language :-) At this point it looks simpler for all people 
to change 3 lines of simulavr source code instead of reading the 
simulavr manual for the "how to config the decoder for special 
instructions".

Is there really someone who needs a additional config file to get all 
the options in? I compile the tool in 3 or 4 seconds and change the 
behavior of an instruction in less then a minute. So the solution we 
discuss did not give more flexibility then the open source code itself.

But if someone wants to implement a simulavr configuration language... 
:-) I will not working on this topic. There are a lot more jobs todo. If 
some one can spend some time on twi? for mega128 and others? ;)

Regards
 Klaus