PowerPC

(processor, standard)(PPC) A RISC microprocessor designedto meet a standard which was jointly designed by Motorola,IBM, and Apple Computer (the PowerPC Alliance). ThePowerPC standard specifies a common instruction set architecture (ISA), allowing anyone to design and fabricatePowerPC processors, which will run the same code. The PowerPCarchitecture is based on the IBM POWER architecture, used inIBM's RS/6000 workstations. Currently IBM andMotorola are working on PowerPC chips.

The PowerPC standard specifies both 32-bit and 64-bit datapaths. Early implementations were 32-bit (e.g. PowerPC 601); later higher-performance implementations were 64-bit(e.g. PowerPC 620). A PowerPC has 32 integer registers (32-or 64 bit) and 32 floating-point (IEEE standard 64 bit)floating-point registers.

The POWER CPU chip and PowerPC have a (large) common core, butboth have instructions that the other doesn't. The PowerPCoffers the following features that POWER does not:

Support for running in little-endian mode.

Addition of single precision floating-point operations.

Control of branch prediction direction.

A hardware coherency model (not in Book I).

Some other floating-point instructions (some optional).

The real time clock (upper and lower) was replaced with thetime base registers (upper and lower), which don't count insec/ns (the decrementer also changed).

64-bit instruction operands, registers, etc. (in 64 bitprocessors).

See also PowerOpen, PowerPC Platform (PReP).

IBM PPC info.

gopher://info.hed.apple.com/, "Apple Corporate News/"(press releases), "Apple Technologies/" and "ProductInformation/". gopher://ike.engr.washington.edu/, "IBMGeneral News/", "IBM Product Announcements/", "IBM DetailedProduct Announcements/", "IBM Hardware Catalog/".

Usenet newsgroups: news:comp.sys.powerpc,news:comp.sys.mac.hardware.

["Microprocessor Report", 16 October 1991].

PowerPC

A family of RISC-based CPU chips developed by IBM, Apple and Motorola. PowerPC chips have been used in a wide range of applications from embedded systems to supercomputers. They were used in Apple's Power Macs up to the G5, before Apple switched to Intel processors. Various models of IBM's System i and System p computers used PowerPC chips, and Freescale Semiconductor (formerly the Motorola chip division) features the Power Architecture for embedded systems in a variety of industries.

Although mostly compatible before, starting in 2006 with Power ISA 2.03, PowerPC chips were united in a common instruction set architecture (ISA) with IBM's POWER chips. For more information, visit www.power.org. See Power Mac, G5, POWER CPU, Power Systems, Apple-IBM Alliance and CHRP.

 WordPowerPC Size Tran-Model Year (bits) sistors Notes Qor series 2008 64 Comms eSeries 2006 32-64 Automotive 970 2003 64 52M Mac G5 7400 1999 32 10.5M Mac G4 750 1997 32 6.4M Mac G3 740 1997 32 6.4M Mac G3 604e 1996 32 5.1M 603e** 1996 32 2.6M 603 1995 32 1.6M 604 1995 32 3.6M 602** 1995 32 1M 601 1993 32 2.8M ** low power for laptops

PowerPC

PowerPC

PowerPC

POWERPC