As there's manual input ( button push ), you could use millis() of the first button press as a random seed, too.
Or simply call random(); in the beginning of loop() where now is your randomSeed(), this will be repeated an undefinite number of times, until both buttons are pressed.
BTW: Your code does not generate a sequence at all, as it never ends the loop().
Strange design... you need to press 3 buttons: Reset, then the 2 others together.
Thanks all.
It's working for the purpose we want.
And yes, it's a strange design, but we have no time to make it better.
(pupils always start to late with their projects...)
RandallR:
Would this still allow you to continue to service interrupts?
No. exit disables interrupts.
I assume the Watch Dog would still restart, even after an exit.
If the watchdog is configured to generate an interrupt the interrupt is ignored. If the watchdog is configured to reset the processor then, when it expires, the processor is reset.