By using events, it is possible to notify various states (conversion end, error occurrence, etc.) that occurred during device operation to application programs.
Depending on the parameters passed in the event notification, you can get what kind of event occurred, and you can sort the processing by event.
Callback Function
A previously created callback function is registered, and the driver
calls the registered function directly when notifying.
It is necessary to handle pointers and function pointers, but the amount
of code is small and simple.