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make use of the 68851 primarily because it can only be used with a small range of processors and most Amigas and accelerator cards use a processor which either has its own MMU or cannot support an MMU. One of the few cards which does use this is the
Commodore A2620.
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have an internal MMU, and will not operate with the 68851, except possibly by simulation of the coprocessor interface.
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Virtual was released in early 1989 and used the 68851 to provide virtual memory, which was later integrated into
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using that processor's coprocessor interface. In theory it can be used with other processors such as the
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35:(MMU) which is designed to provide paged memory support for the
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Motorola-Freescale-NXP processors and microcontrollers
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by simulating the coprocessor interface in software.
61:The 68851 was available as an option for the Apple
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121:"Guide to the Macintosh family hardware"
46:Later 68K family processors such as the
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136:"Commodore A2620 Accelerator Board"
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65:, and was necessary to run Apple's
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748:. You can help Knowledge by
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123:. August 1991. p. 27.
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69:operating system. On the
805:Computer hardware stubs
460:Memory management units
220:Industrial control unit
84:Very few cards for the
33:Memory Management Unit
24:
134:San, Jen (May 1989).
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107:"MC68851 Datasheet"
140:Antic's Amiga Plus
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742:computer hardware
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142:. pp. 37–39.
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795:68k architecture
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579:Microcontrollers
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356:Embedded system
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31:is an external
20:Motorola 68851
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800:Virtual memory
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162:Motorola 68451
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71:classic Mac OS
29:Motorola 68851
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744:article is a
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673:DSPcontroller
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750:expanding it
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705:PowerPC 5000
578:
473:
436:coprocessors
293:68000 family
256:Hitachi 6309
211:
139:
129:
115:
101:
83:
63:Macintosh II
60:
45:
28:
26:
237:6800 family
789:Categories
700:PowerQUICC
531:PowerQUICC
346:DragonBall
254:see also:
212:Processors
157:Amiga 2500
93:References
646:16/32-bit
593:6801/6803
541:PPC e6500
526:PPC e5500
361:-variants
75:Connectix
669:DSP568xx
517:PPC 74xx
512:PPC e500
493:PPC e200
341:ColdFire
151:See also
79:System 7
507:PPC 7xx
498:PPC 6xx
484:PowerPC
421:MC88110
416:MC88100
398:68LC060
393:68EC060
388:68LC040
383:68EC040
378:68EC030
373:68EC020
368:68EC000
695:MPC5xx
690:M·CORE
683:32-bit
662:24-bit
637:68HC16
632:68HC12
627:68HC11
610:68HC08
605:68HC05
486:family
438:(FPUs)
283:68HC16
278:68HC12
273:68HC11
268:68HC08
263:68HC05
54:, and
740:This
653:683xx
587:8-bit
536:QorIQ
474:68851
469:68451
462:(MMU)
450:68882
445:68881
408:88000
336:68060
331:68040
326:68030
321:68020
316:68012
311:68010
306:68008
301:68000
227:14500
86:Amiga
56:68060
52:68040
48:68030
41:68010
37:68020
746:stub
710:i.MX
620:RS08
601:6804
597:6802
559:i.MX
521:e600
502:e300
250:6809
245:6800
67:A/UX
27:The
615:S08
551:ARM
359:68k
22:die
791::
138:.
81:.
73:,
50:,
777:e
770:t
763:v
752:.
519:/
500:/
190:e
183:t
176:v
109:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
