I am using an Arduino on an I2C connected as a slave to a Pi. When the Arduino receives a command, I want it to blink x number of times. The problem I am concerned about is that the interrupt routine should be as short as possible and avoid delays. How should I execute a series of blinks that will occur over >15 seconds?
What is the rule of thumb for interrupt routines? Is there a max number of cycles I should stay within?