PaulS
The comment is wrong. Some (maybe even many) interrupts will happen while your interrupt is detached.
Does this have any connection with my question or is this just an observation of my code comments?
Your offer a statement that the interrupt is detached for a long time. Is this why a see a limit at around 7000 RPM? Thank you for telling me what's wrong but it doesn't give me an opportunity to learn or move forward.
Simon