Chapter 1 CoE Drive Overview ASDA A2-E Link Activity (L/A) LED The L/A LED indicator shows the physical link status and the link activity. Revision April, 2015 1-5 Indicator state Slave State Off No link Blinking Link and activity On Link without activity No link: The link has not established yet. Link and activity: The data is exchanging with its partners. Link without activity: The link is established but no data is exchanging now.