BCM43907 Preliminary Data Sheet
IEEE 802.11n MAC
The IFS module also contains the PTA hardware that assists the PSM in Bluetooth coexistence functions.
TSF
The timing synchronization function (TSF) module maintains the TSF timer of the MAC. It also maintains the
target beacon transmission time (TBTT). The TSF timer hardware, under the control of the PSM, is capable of
adopting timestamps received from beacon and probe response frames in order to maintain synchronization
with the network.
The TSF module also generates trigger signals for events that are specified as offsets from the TSF timer, such
as uplink and downlink transmission times used in PSMP.
NAV
The network allocation vector (NAV) timer module is responsible for maintaining the NAV information conveyed
through the duration field of MAC frames. This ensures that the MAC complies with the protection mechanisms
specified in the standard.
The hardware, under the control of the PSM, maintains the NAV timer and updates the timer appropriately based
on received frames. This timing information is provided to the IFS module, which uses it as a virtual carrier-
sense indication.
MAC-PHY Interface
The MAC-PHY interface consists of a data path interface to exchange RX/TX data from/to the PHY. In addition,
there is an programming interface that can be controlled either by the host or the PSM to configure and control
the PHY.
Broadcom®
March 12, 2016 • 43907-DS104-R
Page 48
BROADCOM CONFIDENTIAL
CYPRESS [ CYPRESS ]
