I am a software guy (everyone immediately downvotes...) trying do the following:
(1) On a BeagleBone Black ("BBB") I am driving a GPIO pin high in software.
(2) Then I am sending PCM (audio) out another pin as I2S serial.
I want to measure the time between (1) and (2). Of course I could use an oscilloscope, but I want to do the measurement 1000 times and take an average. So I plan to use an Arduino as a timer (I've already written and tested the software using push-buttons as inputs). My question: how do I connect the BBB to the Arduino?
I realize I must connect the GPIO pin of the BBB to an input pin on the Arduino. And the I2S serial pin of the BBB to another input pin on the Arduino.
Is that it? Do I connect the GND of the BBB to the GND of the Arduino as well? And do I need to worry about the 3.3v output from the BBB (both pins) to the inputs on a 5v Arduino?