in test "GPIO Button LED Callback (SC589 SHARC)" for board "ADSP-SC589 EZ-BOARD", the delay between pressing the button and turning on the LED 51 μs. 51 microseconds is 22950 core cycles with a core frequency of 450 MHz. why is the interrupt being processed so long? In this example, only one interrupt! can you give an example code for faster interrupt operation?