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AT76C505A

2389BS–WLAN–07/03

Description

The AT76C505A is a single-chip baseband controller that can handle IEEE 802.11b

standard compliant data rates of up to 11 Mbps and provides all processing and func-

tionality needed for the MAC protocol of IEEE 802.11b. The AT76C505A is a full speed

USB 2.0 compliant device that can support up to four configurable Endpoints (EP) plus

one Control EP. The AT76C505A USB interface can support Suspend and Resume bus

condition for saving power during host idle periods.

Besides the USB interface, the AT76C505A contains a WEP/TKIP engine block, an

AES engine block, a MAC Support Unit (MSU), a 802.11b baseband controller, two

memory controllers and the ARM

32-bit timers, and an address decoder unit.

The ARM7TDMI core supports two alternative instruction sets. Powerful 32-bit code can

be executed by the processor in ARM operating mode. However, a 16-bit instruction

subset is also available in Thumb

processor power with limited external memory resources. Note that ARM7TDMI operat-

ing mode can be changed at run time with negligible overhead.