Description
The Cirrus Logic CS22220 Wireless Network Controller enables high performance, 11 Megabits per second digital wireless data connectivity for PCMCIA, mobile, embedded systems and other cost sensitive applications.

Features
Embedded ARM Core and System Support Logic
• High performance ARM7TDMI RISC processor core up to 77MHz
• 4KB integrated, one-way set associative, unified, write through cache
• Individual interrupt for each functional block
• Two 23-bit programmable (periodic or one-shot) general purpose timers
• 8 Dword (32-bits) memory write and read buffers for high system performance
• Abort cycle detection and reporting for debugging
• ARM performance monitoring function for system fine-tuning
• Programmable performance improvement logic based on system configuration

Enhanced Memory Controller Unit
• Programmable memory controller unit supporting SDRAM /async SRAM/Boot ROM/Flash interface
• 16-bit data bus with 12-bit address supporting up to 4MB up to 103 MHz (100/133MHz SDRAM)
• 8-bit data bus with addressing support up to 1MB of boot ROM/Flash.
• Programmable SDRAM timing and size parameters such as CAS latencies and number of banks, columns, and rows
• Flexible independent DMA engines for PCMCIA and digital radio functional units

FEC codec
• High performance Reed-Solomon coding for error correction (255:239 block coding)
• Reduces error probability of a typical 10e-3 error rate environment to 10e-9
• Programmable rate FEC engine to optimize channel efficiency
• Low latency, fully pipelined hardware encoding and decoding. Supports byte-wise single cycle throughput up to 77MHz, with a sustain rate of 77MBps.
• Double buffering (63 Dword read/write buffer) to enhance system performance

Digital Radio MAC Interface
• Glue-less interface to 802.11b baseband transceivers
• Up to 11Mbps data rates
• 32 Dword transmit/receive FIFO
• Supports clear channel assessment (CCA)

Power Management
• Host (PCMCIA) ACPI compliant
• Programmable sleep timer for ARM core and system low power management
• Independent power management control for individual functional units
• Supports variable rate radio transmit, receive, and standby radio power modes

Clock and PLL Interface
• Single 44MHz crystal oscillator reference clock
• Internal PLL to generate internal and on board clocks

PCMCIA Interface
• 16 bit PCMCIA I/O target device supporting memory map or program I/O using 11 address bits
• Independent DMA controller to transfer data between PCMCIA and main memory
• Fully compliant with PCMCIA 2.1/JEIDA 4.2 standard
• Supports big endian and little endian (default) data formats
• Supports custom mode for embedded applications where the interface becomes a generic memory address/data interface

Chip Processing and Packaging
• 208 FPBGA package and 0.18um state of the art CMOS process
• 1.8 V core for low power consumption. 3.3V I/O - 5V tolerant I/O