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Motorola Inc. and International Business Machines Corp. unveiled the first low-power version of the PowerPC family- the PowerPC 603 microprocessor. The 603 is the first processor in the PowerPC family to fully support the PowerPC Architecture. It incorporates five execution units: branch, integer, floating-point, load/store, and system register; and a pair of on-chip 8KB instruction and data caches. Since the 603 is a super-scalar microprocessor, it is capable of issuing and retiring as many as three instructions per clock to these execution units. The memory subsystem provides the instructions for the instruction fetcher and data for the load/store unit. Efficient access between the caches and memory systems is provided by the external bus interface. The 603 incorporates two 8KB, 2-way set associative, 32-byte per line on-chip caches, one for instructions and one for data. On a cache hit, the instructional cache can provide 2 instructions per cycle to the instruction queue, and the data-cache can provide up to a double-word of data to the load/store unit per cycle.

At the Somerset design facility in Austin, Texas, engineers from each of the three companies: Apple computer Inc., International Business Machines Corp., and Motorola Inc. have designed PowerPC micro-processors, employing a formal design methodology drawn from the best of IBM's and Motorola's development environments. With designs completed on schedule for the first two PowerPC family members, the PowerPC 601 and PowerPC 603 microprocessors-the computing industry can expect a steady stream of PowerPC microprocessors satisfying a broad range of market requirements to be introduced in the years to come. The PowerPC architects paid particular attention to defining PowerPC Architecture details, making it flexible and scalable, thus providing plenty of room for growth across a varied family of processors suitable for a wide range of designs from high-performance, multiprocessing systems to handheld computing devices. In addition, the definition of the architecture ensures a guaranteed common software environment for operating system and applications software developers.