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Motorola 68451

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treated memory access errors, i.e. processor state could not always be properly restored after a page fault; two MC68000s would be required, with the main CPU pausing when it got a memory access error, and the other CPU servicing the page fault. The limitation to 32 segment table entries per MMU made
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with support for memory management and protection of memory against unauthorized access. The block size was variable, so it was usually used for segment-based memory management. It supported the mapping of up to 32 memory segments or pages of a variable size from logical to physical addresses. To
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Motorola made a single-board computer module that demonstrated the combination of 68010 and 68451 for applications requiring virtual memory.
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allow more segments or pages, the simultaneous use of multiple MC68451 MMUs was supported
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and a MC68451 slow, as they often had to modify the segment table due to its small size.
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The MC68451 supported a 16 MB address space and provided a
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Motorola-Freescale-NXP processors and microcontrollers
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Virtual memory using the MC68000 and the MC68451 MMU
46:. Unsourced material may be challenged and removed. 926: 259:(Datasheet). Motorola. April 1983. p. 4.-1. 909: 326: 190:, this was not possible due to the way the 182:, the MC68451 permitted the realization of 916: 902: 333: 319: 206:used 12 MC68451 MMUs together with their 106:Learn how and when to remove this message 154: 146: 927: 314: 872: 720: 44:adding citations to reliable sources 15: 13: 14: 956: 876: 20: 210:variant vBertOS. Others (e.g. 31:needs additional citations for 353: 263: 253:MC68451 MEMORY MANAGEMENT UNIT 244: 1: 295:. 30 January 1984. p. 72 237: 218:) used their own proprietary 888:. You can help Knowledge by 884:This computing article is a 7: 225: 10: 961: 871: 826: 805: 789: 730: 719: 715: 693: 626: 602: 575: 550: 498: 435: 379: 363: 352: 348: 940:Motorola microprocessors 222:instead of the MC68451. 604:Memory management units 364:Industrial control unit 216:Convergent Technologies 178:In combination with a 163: 152: 132:Memory Management Unit 158: 150: 40:improve this article 195:systems based on a 186:. With the earlier 164: 153: 897: 896: 866: 865: 862: 861: 711: 710: 159:Motorola MC68451 116: 115: 108: 90: 952: 935:68k architecture 918: 911: 904: 880: 873: 723:Microcontrollers 717: 716: 350: 349: 335: 328: 321: 312: 311: 305: 304: 302: 300: 285: 279: 278: 277: 267: 261: 260: 258: 248: 212:Sun Microsystems 151:Motorola MC68451 111: 104: 100: 97: 91: 89: 55:"Motorola 68451" 48: 24: 16: 960: 959: 955: 954: 953: 951: 950: 949: 945:Computing stubs 925: 924: 923: 922: 869: 867: 858: 822: 801: 785: 726: 707: 689: 622: 598: 571: 546: 500:Embedded system 494: 431: 375: 359: 344: 339: 309: 308: 298: 296: 287: 286: 282: 275: 269: 268: 264: 256: 250: 249: 245: 240: 228: 112: 101: 95: 92: 49: 47: 37: 25: 12: 11: 5: 958: 948: 947: 942: 937: 921: 920: 913: 906: 898: 895: 894: 881: 864: 863: 860: 859: 857: 856: 851: 846: 841: 836: 830: 828: 824: 823: 821: 820: 819: 818: 809: 807: 803: 802: 800: 799: 793: 791: 787: 786: 784: 783: 778: 773: 768: 767: 766: 761: 751: 746: 743: 738: 734: 732: 728: 727: 713: 712: 709: 708: 706: 705: 699: 697: 691: 690: 688: 687: 682: 677: 672: 667: 658: 653: 648: 639: 633: 631: 624: 623: 621: 620: 615: 609: 607: 600: 599: 597: 596: 591: 585: 583: 577:Floating-point 573: 572: 570: 569: 568: 567: 556: 554: 548: 547: 545: 544: 539: 534: 529: 524: 519: 514: 508: 506: 496: 495: 493: 492: 487: 482: 477: 472: 467: 462: 457: 452: 447: 441: 439: 433: 432: 430: 429: 424: 419: 414: 409: 404: 403: 402: 391: 385: 383: 377: 376: 374: 373: 367: 365: 361: 360: 346: 345: 338: 337: 330: 323: 315: 307: 306: 280: 262: 242: 241: 239: 236: 235: 234: 232:Motorola 68851 227: 224: 204:H. Berthold AG 184:virtual memory 142:microprocessor 114: 113: 28: 26: 19: 9: 6: 4: 3: 2: 957: 946: 943: 941: 938: 936: 933: 932: 930: 919: 914: 912: 907: 905: 900: 899: 893: 891: 887: 882: 879: 875: 874: 870: 855: 852: 850: 847: 845: 842: 840: 837: 835: 832: 831: 829: 825: 817:DSPcontroller 816: 815: 814: 811: 810: 808: 804: 798: 795: 794: 792: 788: 782: 779: 777: 774: 772: 769: 765: 762: 760: 757: 756: 755: 752: 750: 747: 744: 742: 739: 736: 735: 733: 729: 725: 724: 718: 714: 704: 701: 700: 698: 696: 692: 686: 683: 681: 678: 676: 673: 671: 668: 666: 662: 659: 657: 654: 652: 649: 647: 643: 640: 638: 635: 634: 632: 629: 625: 619: 616: 614: 611: 610: 608: 605: 601: 595: 592: 590: 587: 586: 584: 581: 578: 574: 566: 563: 562: 561: 558: 557: 555: 553: 549: 543: 540: 538: 535: 533: 530: 528: 525: 523: 520: 518: 515: 513: 510: 509: 507: 504: 501: 497: 491: 488: 486: 483: 481: 478: 476: 473: 471: 468: 466: 463: 461: 458: 456: 453: 451: 448: 446: 443: 442: 440: 438: 434: 428: 425: 423: 420: 418: 415: 413: 410: 408: 405: 401: 397: 396: 395: 392: 390: 387: 386: 384: 382: 378: 372: 369: 368: 366: 362: 358: 357: 351: 347: 343: 336: 331: 329: 324: 322: 317: 316: 313: 294: 293:Computerworld 290: 284: 274: 273: 266: 255: 254: 247: 243: 233: 230: 229: 223: 221: 217: 213: 209: 205: 200: 198: 193: 189: 185: 181: 176: 173: 169: 162: 157: 149: 145: 143: 140: 137: 133: 129: 125: 121: 110: 107: 99: 88: 85: 81: 78: 74: 71: 67: 64: 60: 57: –  56: 52: 51:Find sources: 45: 41: 35: 34: 29:This article 27: 23: 18: 17: 890:expanding it 883: 868: 849:PowerPC 5000 722: 612: 580:coprocessors 437:68000 family 400:Hitachi 6309 355: 297:. Retrieved 292: 283: 271: 265: 252: 246: 201: 177: 165: 119: 117: 102: 93: 83: 76: 69: 62: 50: 38:Please help 33:verification 30: 381:6800 family 929:Categories 844:PowerQUICC 675:PowerQUICC 490:DragonBall 398:see also: 356:Processors 238:References 66:newspapers 790:16/32-bit 737:6801/6803 685:PPC e6500 670:PPC e5500 505:-variants 128:Freescale 96:July 2022 813:DSP568xx 661:PPC 74xx 656:PPC e500 637:PPC e200 485:ColdFire 226:See also 136:Motorola 124:Motorola 651:PPC 7xx 642:PPC 6xx 628:PowerPC 565:MC88110 560:MC88100 542:68LC060 537:68EC060 532:68LC040 527:68EC040 522:68EC030 517:68EC020 512:68EC000 299:19 June 197:MC68010 192:MC68000 188:MC68000 180:MC68010 172:MC68010 168:MC68000 139:MC68010 120:MC68451 80:scholar 839:MPC5xx 834:M·CORE 827:32-bit 806:24-bit 781:68HC16 776:68HC12 771:68HC11 754:68HC08 749:68HC05 630:family 582:(FPUs) 427:68HC16 422:68HC12 417:68HC11 412:68HC08 407:68HC05 82:  75:  68:  61:  53:  797:683xx 731:8-bit 680:QorIQ 618:68851 613:68451 606:(MMU) 594:68882 589:68881 552:88000 480:68060 475:68040 470:68030 465:68020 460:68012 455:68010 450:68008 445:68000 371:14500 276:(PDF) 257:(PDF) 170:or a 126:(now 122:is a 87:JSTOR 73:books 886:stub 854:i.MX 764:RS08 745:6804 741:6802 703:i.MX 665:e600 646:e300 394:6809 389:6800 301:2024 220:MMUs 208:UNOS 118:The 59:news 759:S08 695:ARM 503:68k 161:die 42:by 931:: 291:. 214:, 144:. 130:) 917:e 910:t 903:v 892:. 663:/ 644:/ 334:e 327:t 320:v 303:. 109:) 103:( 98:) 94:( 84:· 77:· 70:· 63:· 36:.

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"Motorola 68451"
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Motorola
Freescale
Memory Management Unit
Motorola
MC68010
microprocessor


die
MC68000
MC68010
MC68010
virtual memory
MC68000
MC68000
MC68010
H. Berthold AG
UNOS
Sun Microsystems

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