The problem with instruction set tests is how do you test something using the very thing that you are intending to test??

What happens of some of the first instructions out of reset at the ones that fail?

What if an instruction failure ends up altering the execution flow of the test program itself causing it to crash?

If one of the instructions executed in the code logic that tries to verify the results of the IUT (instruction under test) happens to be one that fails can you ever trust the test results?

At best you can say that if an Instruction Set Test happens to execute smoothly to its end then you can say - Everything appears OK. On the other side of things any failure may be indicate something has gone wrong. You cannot be sure of what caused it but you know there was a failure.

If you do intend to write an instruction set test make sure to enable the watch Dog timer so that there is some chance of recovering the MCU if it goes out into the weeds during the test.

Michael Karas