Port manipulation

I'm assuming the asm(); is a function that sends data to the port?

And this led strip is probably sent data through rapid successions of "asm("nop\n\t");"

Is there any good way of monitoring what's being sent out of my pins so I can check my theory? I've tried simply placing serial.println() in the sendstrip functions and it won't output anything and stops the functionality of the led strip D: