8

ATL25SeriesASIC

1414C–ASIC-08/02

32-bit RISC

Microprocessor

Core

The ARM920T extends the capabilities of the popular ARM7TDMI, while maintaining code

compatibility and Thumb instruction compression. Enhancements include Harvard architecture

and a memory management unit with virtual addressing support (allowing the use of advanced

16 Kbyte data and instruction caches are included.

32-bit RISC

Microprocessor

Core

The ARM946E-S is a synthesizable version of the ARM9E-S core, with similar features to the

ARM920T. The ARM9E-S instruction set adds saturation logic to enhance DSP implementa-

tion, as well as double-word data moves. Additional DSP features include a single cycle

16 x 32 Multiply Accumulate (MAC) Unit. A memory protection unit is provided, but without full

virtual memory support. As a result, the ARM946E-S is more suited to deeply embedded tasks

that do not require extended-platform OS support. Cache sizes can be tailored to the applica-

tion, resulting in a (potentially) smaller die size compared to the ARM920T.

Digital Signal

Processing Core

Atmel’s hard macro OakDSPCore is a 16-bit, general purpose, low-power, low-voltage and

high-speed Digital Signal Processor (DSP).

Oak is designed for mid-to-high-end telecommunications and consumer electronics applica-

tions, where low-power and portability are major requirements. Among the applications

supported are digital cellular telephones, fast modems, advanced facsimile machines and hard

disk drives. Oak is available as a DSP core in Atmel’s ASIC cell library, to be utilized as an

engine for a DSP-based ASIC. It is specified with several levels of modularity in SRAM, ROM

and I/O blocks, allowing efficient DSP-based ASIC development.

Oak is aimed at achieving the best cost-performance factor for a given (small) silicon area. As

a key element of a system-on-chip, it takes into account such requirements as program size,

data memory size, glue logic and power management.

The Oak core consists of three main execution units operating in parallel: the Computation/Bit-

Manipulation Unit (CBU), the Data Addressing Arithmetic Unit (DAAU) and the Program Con-

trol Unit (PCU).

The core also contains ROM and SRAM addressing units, and Program Control Logic (PCL).

All other peripheral blocks that are application specific are defined as part of the user-specific

logic and implemented around the DSP core on the same silicon die.

Oak has an enhanced set of DSP and general microprocessor functions to meet most applica-

tion requirements. The Oak programming model and instruction set are aimed at the

straightforward generation of efficient and compact code.

64-bit RISC

Microprocessor

Core

The MIPS64 5Kf is a synthesizable MIPS64 5K family core that provides 64-bit address and

data paths along with an onboard IEEE 754-compliant Floating Point Unit. A built-in memory

management unit with virtual addressing support allows the use of platform operating systems

such as Windows CE and others. Also provided are configurable instruction and data caches,

as well as a multiply divide unit capable of single cycle 32 x 16 Multiply Accumulate (MAC)

operations.

Teak and

Digital Signal

Processing Cores

The Teak and Palm are synthesizable dual-MAC DSP cores from DSP Group, Inc. The Teak

is a fixed-point 16-bit DSP, whereas the Palm can be configured for 16-bit, 20-bit or 24-bit

fixed-point math. Both cores are optimized for high MIPs per mW, with performance targeted

to handling filtering, voice compression/decompression and modem functions for portable and

wireless applications such as 3G digital cellular. Hardware support is also provided for imple-

menting Viterbi forward error correction.