PowerPC (redirected from MPC601)

PowerPC

A family of RISC-based CPU chips developed by IBM, Apple and Motorola. The PowerPC, known as the "Power Architecture," is governed by Power.org and dates back to the first IBM POWER CPU in the RS/6000 in 1990. For more information, visit www.power.org.

PowerPC chips have been used in a wide range of computing devices from handheld machines to supercomputers. The chips were used in Apple's Power Mac line up to and including the G5, which was the last Mac model before Apple switched to Intel x86-based processors. Various models of IBM's System i (iSeries) and System p (pSeries) used PowerPC chips, and Freescale Semiconductor, formerly Motorola's chip division, has featured PowerPC chips for automotive powertrain control.

Although mostly compatible, starting in 2006 with Power ISA 2.03, the PowerPC and POWER chips were united into a common instruction set architecture (ISA). See Power Mac, POWER, Power Systems, Apple-IBM Alliance and CHRP.

                     Word
   PowerPC   Year    Size   # of    Macintosh
   Model     Intro. (bits)  Trans.  Models

   970       2003     64    52M     G5

   7400      1999     32  10.5M     G4

   750       1997     32   6.4M     G3

   740       1997     32   6.4M     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

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(processor, standard)

PowerPC - (PPC) A RISC microprocessor designed to meet a standard which was jointly designed by Motorola, IBM, and Apple Computer (the PowerPC Alliance). The PowerPC standard specifies a common instruction set architecture (ISA), allowing anyone to design and fabricate PowerPC processors, which will run the same code. The PowerPC architecture is based on the IBM POWER architecture, used in IBM's RS/6000 workstations. Currently IBM and Motorola are working on PowerPC chips. The PowerPC standard specifies both 32-bit and 64-bit data paths. 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, but both have instructions that the other doesn't. The PowerPC offers 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 the time base registers (upper and lower), which don't count in sec/ns (the decrementer also changed). 64-bit instruction operands, registers, etc. (in 64 bit processors). See also PowerOpen, PowerPC Platform (PReP). IBM PPC info. gopher://info.hed.apple.com/, "Apple Corporate News/" (press releases), "Apple Technologies/" and "Product Information/". gopher://ike.engr.washington.edu/, "IBM General News/", "IBM Product Announcements/", "IBM Detailed Product Announcements/", "IBM Hardware Catalog/". Usenet newsgroups: news:comp.sys.powerpc, news:comp.sys.mac.hardware. ["Microprocessor Report", 16 October 1991].