Hi Fabio,

I tested your code with the callback fll using timeSetEvent() and intervals ranging from 10 to 1000 ms
The vfpcode was interrupted (during update and replace)

Behaviour

the shorter the interval the more frequent the errors like
- function giro(): error : No parameters statement found
- during the update : data type mismatch (I suspect the return from giro() was misinterpreted)

After an error either an immediate crash or vfp had become instable and crashed afterwards

Conclusion of the tests (choose either one)

There must be a good reason why vfp saves the events and gives a burst afterwards.
The callback fll has bugs

I suspect vfp turns off timer events during critical operations (eg update). After that the number of missed events is calculated and caught up (the burst)