1124:
1102:
62:
carries the actual data being processed, the control bus carries commands from the CPU and returns status signals from the devices. For example, if the data is being read or written to the device the appropriate line (read or write) will be active
150:
112:
183:
333:
323:
1165:
1097:
Interfaces are listed by their speed in the (roughly) ascending order, so the interface at the end of each section should be the fastest.
317:
542:
257:
have additional control bus signals that control which bus master drives the address bus, avoiding bus contention on the address bus.
1070:
699:
341:
562:
369:
17:
750:
421:
327:
456:
803:
642:
572:
75:
The number and type of lines in a control bus varies but there are basic lines common to all microprocessors, such as:
1158:
632:
1189:
730:
202:
522:
1074:
725:
694:
347:
27:
This article is about a kind of bus used inside one box. For a kind of bus that connects several boxes in a
1151:
672:
998:
937:
792:
597:
362:
967:
123:
85:
652:
161:
28:
1184:
1105:
1080:
972:
627:
51:
152:). A single line that when active (logic zero) indicates the device is being written by the CPU.
662:
228:
206:("acknowledgement"). Delivers information that the data was acknowledged (read) by the device.
926:
879:
735:
507:
355:
114:). A single line that when active (logic zero) indicates the device is being read by the CPU.
39:
922:
775:
657:
8:
834:
389:
189:
The RD and WR signals of the control bus control the reading or writing of RAM, avoiding
378:
1139:
1131:
824:
446:
382:
241:
58:
carries the information about the device with which the CPU is communicating and the
557:
313:
237:. The signal on this line is used to synchronize data between the CPU and a device.
687:
537:
517:
392:
298:
271:
59:
1135:
988:
682:
607:
532:
436:
411:
212:(BR, BREQ, or BRQ). Indicates a device is requesting the use of the (data) bus.
190:
1178:
1060:
947:
839:
787:
770:
552:
451:
441:
416:
377:
276:
185:). A group of lines that indicate the size of the data (8, 16, 32, 64 bytes).
797:
740:
592:
497:
1065:
1044:
962:
807:
745:
720:
647:
431:
266:
246:
55:
1123:
884:
918:
617:
406:
337:
254:
47:
942:
932:
899:
894:
829:
704:
492:
477:
472:
222:
64:
54:
for communicating with other devices within the computer. While the
952:
889:
622:
482:
32:
1085:
1039:
1023:
849:
667:
612:
547:
502:
1018:
909:
874:
869:
864:
859:
677:
567:
527:
487:
1003:
914:
218:(BG or BGRT). Indicates the CPU has granted access to the bus.
1013:
904:
844:
782:
755:
637:
587:
512:
1008:
993:
854:
765:
760:
602:
957:
582:
577:
196:
Additional lines are microprocessor-dependent, such as:
164:
126:
88:
177:
144:
106:
245:. If this line is active, the CPU will perform a
1176:
700:Coherent Accelerator Processor Interface (CAPI)
301:. 2013. section "The control bus". p. 209-210.
1159:
363:
1166:
1152:
370:
356:
342:California State University, Los Angeles
293:
291:
14:
1177:
351:
288:
1118:
334:"Hardware and Software Architecture"
328:University of California, Riverside
24:
25:
1201:
307:
1122:
1101:
1100:
299:"Practical Electronics Handbook"
253:Systems that have more than one
231:is requesting access to the CPU.
145:{\displaystyle {\overline {WR}}}
107:{\displaystyle {\overline {RD}}}
178:{\displaystyle {\overline {E}}}
13:
1:
695:Intel Ultra Path Interconnect
282:
1138:. You can help Knowledge by
673:Intel QuickPath Interconnect
663:Direct Media Interface (DMI)
324:Computer system organization
170:
137:
99:
7:
297:Ian Sinclair; John Dunton.
260:
227:(IRQ). A device with lower
10:
1206:
1117:
658:Compute Express Link (CXL)
26:
1094:
1053:
1032:
981:
895:IEEE-1284 (parallel port)
817:
810:logical device interface)
713:
465:
399:
70:
29:networked control system
1190:Computer hardware stubs
457:List of bus bandwidths
179:
146:
108:
180:
147:
109:
40:computer architecture
18:Bus grant acknowledge
900:IEEE-1394 (FireWire)
638:PCI Extended (PCI-X)
162:
124:
86:
741:Parallel ATA (PATA)
648:PCI Express (PCIe)
175:
142:
104:
1147:
1146:
1132:computer hardware
1112:
1111:
1098:
825:Apple Desktop Bus
802:PCI Express (via
761:Serial ATA (SATA)
447:Network on a chip
193:on the data bus.
173:
140:
102:
16:(Redirected from
1197:
1168:
1161:
1154:
1126:
1119:
1104:
1103:
1096:
558:HP Precision Bus
372:
365:
358:
349:
348:
340:presentation at
302:
295:
184:
182:
181:
176:
174:
166:
151:
149:
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143:
141:
136:
128:
113:
111:
110:
105:
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98:
90:
21:
1205:
1204:
1200:
1199:
1198:
1196:
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1194:
1175:
1174:
1173:
1172:
1115:
1113:
1108:
1099:
1090:
1049:
1028:
977:
890:IEEE-488 (GPIB)
813:
709:
688:Infinity Fabric
518:Europe Card Bus
461:
395:
376:
310:
305:
296:
289:
285:
263:
165:
163:
160:
159:
129:
127:
125:
122:
121:
91:
89:
87:
84:
83:
73:
50:and is used by
46:is part of the
36:
23:
22:
15:
12:
11:
5:
1203:
1193:
1192:
1187:
1185:Computer buses
1171:
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1047:
1042:
1036:
1034:
1030:
1029:
1027:
1026:
1021:
1016:
1011:
1006:
1001:
999:Intel HD Audio
996:
991:
989:ADAT Lightpipe
985:
983:
979:
978:
976:
975:
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965:
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950:
945:
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935:
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867:
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837:
832:
827:
821:
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815:
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811:
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795:
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773:
763:
758:
753:
748:
743:
738:
733:
728:
723:
717:
715:
711:
710:
708:
707:
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697:
692:
691:
690:
683:HyperTransport
680:
675:
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665:
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645:
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635:
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625:
620:
615:
610:
605:
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560:
555:
550:
545:
540:
535:
530:
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520:
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510:
505:
500:
495:
490:
485:
480:
475:
469:
467:
463:
462:
460:
459:
454:
449:
444:
439:
437:Bus contention
434:
429:
424:
419:
414:
412:Front-side bus
409:
403:
401:
397:
396:
393:computer buses
375:
374:
367:
360:
352:
346:
345:
331:
321:
309:
308:External links
306:
304:
303:
286:
284:
281:
280:
279:
274:
269:
262:
259:
251:
250:
238:
232:
219:
213:
207:
191:bus contention
187:
186:
172:
169:
153:
139:
135:
132:
115:
101:
97:
94:
72:
69:
9:
6:
4:
3:
2:
1202:
1191:
1188:
1186:
1183:
1182:
1180:
1169:
1164:
1162:
1157:
1155:
1150:
1149:
1143:
1141:
1137:
1134:article is a
1133:
1128:
1125:
1121:
1120:
1116:
1107:
1093:
1087:
1084:
1082:
1079:
1076:
1072:
1069:
1067:
1064:
1062:
1061:Multidrop bus
1059:
1058:
1056:
1052:
1046:
1043:
1041:
1038:
1037:
1035:
1031:
1025:
1022:
1020:
1017:
1015:
1012:
1010:
1007:
1005:
1002:
1000:
997:
995:
992:
990:
987:
986:
984:
980:
974:
971:
969:
968:External PCIe
966:
964:
961:
959:
956:
954:
951:
949:
948:Parallel SCSI
946:
944:
941:
939:
936:
934:
931:
928:
924:
920:
916:
913:
911:
908:
906:
903:
901:
898:
896:
893:
891:
888:
886:
883:
881:
878:
876:
873:
871:
868:
866:
863:
861:
858:
856:
853:
851:
848:
846:
843:
841:
840:Commodore bus
838:
836:
833:
831:
828:
826:
823:
822:
820:
816:
809:
805:
801:
799:
796:
794:
791:
789:
788:Fibre Channel
786:
784:
781:
777:
774:
772:
769:
768:
767:
764:
762:
759:
757:
754:
752:
749:
747:
744:
742:
739:
737:
734:
732:
729:
727:
724:
722:
719:
718:
716:
712:
706:
703:
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698:
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693:
689:
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669:
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664:
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659:
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641:
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634:
631:
629:
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621:
619:
616:
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611:
609:
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604:
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599:
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589:
586:
584:
581:
579:
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574:
571:
569:
566:
564:
561:
559:
556:
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551:
549:
546:
544:
541:
539:
536:
534:
531:
529:
526:
524:
521:
519:
516:
514:
511:
509:
506:
504:
501:
499:
496:
494:
491:
489:
486:
484:
481:
479:
476:
474:
471:
470:
468:
464:
458:
455:
453:
452:Plug and play
450:
448:
445:
443:
442:Bus mastering
440:
438:
435:
433:
430:
428:
425:
423:
420:
418:
417:Back-side bus
415:
413:
410:
408:
405:
404:
402:
398:
394:
391:
387:
385:
380:
373:
368:
366:
361:
359:
354:
353:
350:
343:
339:
335:
332:
329:
325:
322:
319:
315:
312:
311:
300:
294:
292:
287:
278:
277:Bus mastering
275:
273:
270:
268:
265:
264:
258:
256:
248:
244:
243:
239:
236:
235:Clock signals
233:
230:
226:
224:
220:
217:
214:
211:
208:
205:
204:
199:
198:
197:
194:
192:
167:
157:
154:
133:
130:
119:
116:
95:
92:
81:
78:
77:
76:
68:
66:
61:
57:
53:
49:
45:
41:
34:
30:
19:
1140:expanding it
1129:
1114:
593:TURBOchannel
426:
383:
252:
240:
234:
221:
215:
209:
200:
195:
188:
155:
117:
79:
74:
43:
37:
1066:CoreConnect
1045:ExpressCard
973:Thunderbolt
963:Camera Link
746:Bus and Tag
432:Address bus
427:Control bus
422:Daisy chain
267:Address bus
247:hard reboot
210:Bus request
156:Byte enable
56:address bus
44:control bus
1179:Categories
919:ACCESS.bus
818:Peripheral
618:InfiniBand
613:HP GSC bus
407:System bus
338:PowerPoint
314:Definition
283:References
255:bus master
48:system bus
880:Lightning
830:Atari SIO
705:SpaceWire
538:Zorro III
478:S-100 bus
473:SS-50 bus
466:Standards
386:standards
379:Technical
318:Webopedia
223:Interrupt
216:Bus grant
201:Transfer
171:¯
138:¯
100:¯
65:logic one
1106:Category
1081:Wishbone
1054:Embedded
1033:Portable
953:Profibus
885:DMX512-A
771:Parallel
623:Ethernet
533:Zorro II
483:Multibus
384:de facto
272:Data bus
261:See also
229:priority
60:data bus
33:Fieldbus
1086:SLIMbus
1040:PC Card
1024:TOSLINK
714:Storage
668:RapidIO
548:FASTBUS
503:STD Bus
400:General
326:at the
225:request
1019:S/PDIF
910:1-Wire
875:RS-485
870:RS-423
865:RS-422
860:RS-232
721:ST-506
678:NVLink
528:STEbus
488:Unibus
31:, see
1130:This
1014:McASP
982:Audio
927:SMBus
923:PMBus
905:UNI/O
845:HP-IL
798:SATAe
783:ESCON
756:HIPPI
588:NuBus
543:CAMAC
513:Q-Bus
508:SMBus
493:VAXBI
390:wired
242:Reset
118:Write
71:Lines
1136:stub
1071:AMBA
1009:MADI
994:AES3
855:MIDI
808:NVMe
804:AHCI
766:SCSI
751:DSSI
726:ESDI
603:SBus
563:EISA
498:MBus
388:for
381:and
336:, a
80:Read
52:CPUs
42:, a
1075:AXI
1004:I²S
958:USB
943:D²B
938:SPI
933:I3C
915:I²C
850:HIL
835:DCB
806:or
793:SSA
776:SAS
736:SMD
731:IPI
653:AGP
643:PXI
633:PCI
628:UPA
608:VLB
598:MCA
583:VPX
578:VXS
573:VXI
568:VME
553:LPC
523:ISA
316:by
203:ACK
67:).
38:In
1181::
925:,
921:,
290:^
1167:e
1160:t
1153:v
1142:.
1077:)
1073:(
929:)
917:(
371:e
364:t
357:v
344:.
330:.
320:.
249:.
168:E
158:(
134:R
131:W
120:(
96:D
93:R
82:(
63:(
35:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.