Abstract: A Carrier Sense Multiple Access with Automatic Abort collision avoidance (CSMA/AA) controller for application in a wireless local area network (LAN). The CSMA/AA controller reduces the number of invalid states arising from collision conditions on the communication channel. The controller features hardware logic control for time critical functions. The hardware logic circuit detects events and fault conditions under the CSMA reservation protocol which may otherwise be missed by the Medium Access Control software layer and aborts the transmit procedure. The off-loading of time critical functions also improves the performance of the system and reduces the variability arising from overhead execution times associated with the system CPU.