Associating
- reset frequency tracking bandwidth to defaults
- set BSSID in address match registers
- update ACK/CTS tables in SHM
- update slot timing
- program ATIM window and CFP duration if appropriate
- reset TSF/write beacon interval and CFP start if starting AP/IBSS
- set mode bits in MAC control register
- enable "beacons promisc" filter bit when starting IBSS
- update Pre-TBTT time (both SHM and MMIO register): 2 if IBSS, otherwise 120 for A PHY, 250 for B/G PHY