MarkT,
in general I do agree, but
- I need to know if the interrupt is working with a minimum (or at least a defined) delay
- the code shows an intervall of 100mS at 115200baud which should be quick enough to submit the data
- the serial data submission is after the interrupt work...shouldn't lead to a delay
But anyhow I do agree that this is not optimum, but I do not know any other way to control function accuracy and I do not have a oscilloscope