Re: How to compare computing power of microcontrollers?

If you don't have hardware for both, I would write a piece of assembly
code "on paper". This code should be represntative of a function that
you will be doing for your application (ie. 16 bit multiplication and
trig). And add up the number of clock cycles it would take each
processor to run the same piece of code.

This calculations assumes each processor has similar instructions and
the compilers you use have a similar optimization routine.

You know the # of clock cycles and the frequency, you can then evaluate
which processor has a better performance for your application.

It is time consuming, but without looking at the Datapath / Instruction
cycles you can't evaluate the performance.

Example: a processor may run at a faster clock frequency, but if the
instructions you are using aren't pipelined well your just burning up
power and not gaining performance.

Multiplication tends to be one of the instructions that is poorly
pipelined in smaller cpus. So the # of instructions that MULT takes
might be a good enough benchmark for your application.

Good Luck,
Eric

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