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2.3 Address Event Representation (AER)
Address-Event-Representation (AER) is a communication protocol that emulates the
nervous system’s neurons communication and that is typically used for transferring
images between chips. It was originally developed for bio-inspired and real-time
image processing systems.[4, 59, 61, 62, 64, 143-159]
2.3.1 The message packet
This consists of a source address segment; determined by the image size containing
the pixel data to be routed, and a payload segment containing the event or train of
events associated to each address. In the case of a train of events not all of the events
would necessarily be there.
Address segment
Payload
Figure 14 message packet
Although the payload can be empty when using the AER protocol (not definitive)
this would imply that the address itself is indicative of an event. The AER packet is
in fact used in this way; when processed after transmission reception, and also for
convenience in the test setup when demonstrating reception of the AER packet for
display to the Digital Video Interfaced (DVI) VGA monitor. However by using a
payload of a pulse count, rather than the way just detailed, bit rate can be reduced
dramatically in the sense that rather than 50 addresses being transmitted for 50
separate events; at maximum intensity, meaning 50 separate AER packets, this
reduces to one AER packet with one payload representing a train of events.
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