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25:
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One huge advantage of having fewer wires/pins in a serial cable is the significant reduction in the size, the complexity of the connectors, and the associated costs. Designers of devices such as smartphones benefit from the development of connectors/ports that are small, durable, and still provide
310:
creates interference between the parallel lines, and the effect worsens with the length of the communication link. This places an upper limit on the length of a parallel data connection that is usually shorter than a serial
195:. Computer system buses, on the other hand, have evolved over time: parallel communication was commonly used in earlier system buses, whereas serial communications are prevalent in modern computers.
469:
299:
reduces the speed of every link to the slowest of all of the links. However, parallel lines have lower latency than serial lines, this makes parallel lines is still used on memory bus like
164:
to convey bits. Parallel communication implies more than one such conductor. For example, an 8-bit parallel channel will convey eight bits (or a
168:) simultaneously, whereas a serial channel would convey those same bits sequentially, one at a time. If both channels operated at the same
1247:
Interfaces are listed by their speed in the (roughly) ascending order, so the interface at the end of each section should be the fastest.
327:
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Before the development of high-speed serial technologies, the choice of parallel links over serial links was driven by these factors:
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172:, the parallel channel would be eight times faster. A parallel channel may have additional conductors for other signals, such as a
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68:
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366:(AV) devices such as digital cameras or professional-grade scanners that used to require purchasing a SCSI HBA years ago.
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75:
953:
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252:
108:
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57:
291:
Speed: Superficially, the speed of a parallel data link is equal to the number of bits sent at one time times the
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46:
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Complexity: Parallel data links are easily implemented in hardware, making them a logical choice. Creating a
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of each individual path; doubling the number of bits sent at once doubles the data rate. In practice,
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326:. In contrast, most serial communication must first be converted back into parallel form by a
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145:, which conveys only a single bit at a time; this distinction is one way of characterizing a
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192:
142:
8:
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146:
121:
528:
386:
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232:(1964). Standard System/360 had an eight-bit wide port. The process-control variant
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414:
130:
707:
484:
837:
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542:
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communication send a few bits in parallel. (Each such group of bits is called a "
374:
323:
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to pace the flow of data, a signal to control the direction of data flow, and
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has led to serial links being used in favor of parallel links; for example,
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On the other hand, there has been a resurgence of parallel data links in
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401:"). Such techniques can be extended to send an entire byte at once (
24:
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355:
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269:
16:
Method of data transmission in which bits are conveyed in parallel
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communication. Rather than transmitting one bit at a time (as in
183:
Parallel communication is and always has been widely used within
141:) simultaneously using multiple conductors. This contrasts with
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1024:
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1014:
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are now the most common connectors for transferring data from
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1054:
994:
932:
905:
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198:
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in a computer system is relatively simple, requiring only a
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1004:
915:
910:
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382:
330:(UART) before they may be directly connected to a data bus.
165:
1107:
732:
727:
343:
138:
152:
The basic difference between a parallel and a serial
49:. Unsourced material may be challenged and removed.
137:is a method of conveying multiple binary digits (
1266:
850:Coherent Accelerator Processor Interface (CAPI)
282:
334:The decreasing cost and better performance of
513:
443:
328:universal asynchronous receiver/transmitter
520:
506:
199:Examples of parallel communication systems
109:Learn how and when to remove this message
120:
1267:
447:IBM System/360 Principles of Operation
501:
191:buses, and in memory devices such as
125:Parallel versus serial communication
47:adding citations to reliable sources
18:
216:, including various generations of
13:
239:Legacy computer peripheral buses:
14:
1286:
385:), well-known techniques such as
1251:
1250:
468: This article incorporates
463:
23:
481:General Services Administration
268:Laboratory Instrumentation bus
34:needs additional citations for
437:
395:Multiple-input multiple-output
1:
845:Intel Ultra Path Interconnect
430:
306:Cable length or link length:
823:Intel QuickPath Interconnect
813:Direct Media Interface (DMI)
283:Comparison with serial links
7:
408:
10:
1291:
808:Compute Express Link (CXL)
255:, and the once-ubiquitous
1244:
1203:
1182:
1131:
1045:IEEE-1284 (parallel port)
967:
960:logical device interface)
863:
615:
549:
58:"Parallel communication"
607:List of bus bandwidths
476:Federal Standard 1037C
470:public domain material
370:adequate performance.
274:(see more examples at
230:Direct Control Feature
135:parallel communication
126:
489: (in support of
425:Bit-level parallelism
158:electrical conductors
154:communication channel
124:
1050:IEEE-1394 (FireWire)
788:PCI Extended (PCI-X)
322:to copy data onto a
143:serial communication
43:improve this article
891:Parallel ATA (PATA)
336:integrated circuits
236:had a 32-bit width.
185:integrated circuits
147:communications link
798:PCI Express (PCIe)
342:printer ports vs.
127:
1275:Data transmission
1262:
1261:
1248:
975:Apple Desktop Bus
952:PCI Express (via
911:Serial ATA (SATA)
597:Network on a chip
444:IBM Corporation.
415:Data transmission
156:is the number of
131:data transmission
119:
118:
111:
93:
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708:HP Precision Bus
522:
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508:
499:
498:
494:
488:
483:. Archived from
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204:Internal buses:
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100:
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92:
51:
27:
19:
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1249:
1240:
1199:
1178:
1127:
1040:IEEE-488 (GPIB)
963:
859:
838:Infinity Fabric
668:Europe Card Bus
611:
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1149:Intel HD Audio
1146:
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1139:ADAT Lightpipe
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833:HyperTransport
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587:Bus contention
584:
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574:
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562:Front-side bus
559:
553:
551:
547:
546:
543:computer buses
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510:
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496:
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487:on 2022-01-22.
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332:
331:
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264:"printer port"
237:
227:IBM System/360
224:
214:front-side bus
200:
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162:physical layer
117:
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31:
29:
22:
15:
9:
6:
4:
3:
2:
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1243:
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1234:
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1226:
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1219:
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1212:
1211:Multidrop bus
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1202:
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1121:
1119:
1118:External PCIe
1116:
1114:
1111:
1109:
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1101:
1099:
1098:Parallel SCSI
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1038:
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1021:
1018:
1016:
1013:
1011:
1008:
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990:Commodore bus
988:
986:
983:
981:
978:
976:
973:
972:
970:
966:
959:
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951:
949:
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939:
938:Fibre Channel
936:
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919:
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621:
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602:Plug and play
600:
598:
595:
593:
592:Bus mastering
590:
588:
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583:
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575:
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568:
567:Back-side bus
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316:parallel port
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113:
110:
102:
91:
88:
84:
81:
77:
74:
70:
67:
63:
60: –
59:
55:
54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
743:TURBOchannel
533:
485:the original
475:
446:
439:
372:
368:
348:Parallel ATA
333:
286:
276:computer bus
229:
182:
174:clock signal
160:used at the
151:
134:
128:
105:
99:January 2008
96:
86:
79:
72:
65:
53:
41:Please help
36:verification
33:
1216:CoreConnect
1195:ExpressCard
1123:Thunderbolt
1113:Camera Link
896:Bus and Tag
582:Address bus
577:Control bus
572:Daisy chain
491:MIL-STD-188
420:Serial port
364:audiovisual
360:Thunderbolt
311:connection.
178:handshaking
170:clock speed
1069:ACCESS.bus
968:Peripheral
768:InfiniBand
763:HP GSC bus
557:System bus
431:References
379:Morse code
352:Serial ATA
297:clock skew
261:Centronics
222:GDDR SDRAM
210:system bus
206:memory bus
189:peripheral
69:newspapers
1030:Lightning
980:Atari SIO
855:SpaceWire
688:Zorro III
628:S-100 bus
623:SS-50 bus
616:Standards
536:standards
529:Technical
340:IEEE 1284
308:Crosstalk
301:DDR SDRAM
257:IEEE-1284
218:DDR SDRAM
180:signals.
1269:Category
1256:Category
1231:Wishbone
1204:Embedded
1183:Portable
1103:Profibus
1035:DMX512-A
921:Parallel
773:Ethernet
683:Zorro II
633:Multibus
534:de facto
409:See also
356:FireWire
324:data bus
293:bit rate
270:IEEE-488
234:Model 44
1236:SLIMbus
1190:PC Card
1174:TOSLINK
864:Storage
818:RapidIO
698:FASTBUS
653:STD Bus
550:General
403:256-QAM
83:scholar
1169:S/PDIF
1060:1-Wire
1025:RS-485
1020:RS-423
1015:RS-422
1010:RS-232
871:ST-506
828:NVLink
678:STEbus
638:Unibus
399:symbol
393:, and
354:, and
212:, and
85:
78:
71:
64:
56:
1164:McASP
1132:Audio
1077:SMBus
1073:PMBus
1055:UNI/O
995:HP-IL
948:SATAe
933:ESCON
906:HIPPI
738:NuBus
693:CAMAC
663:Q-Bus
658:SMBus
643:VAXBI
540:wired
472:from
451:(PDF)
320:latch
187:, in
90:JSTOR
76:books
1221:AMBA
1159:MADI
1144:AES3
1005:MIDI
958:NVMe
954:AHCI
916:SCSI
901:DSSI
876:ESDI
753:SBus
713:EISA
648:MBus
538:for
531:and
383:BPSK
381:and
350:vs.
249:SCSI
220:and
166:byte
139:bits
62:news
1225:AXI
1154:I²S
1108:USB
1093:D²B
1088:SPI
1083:I3C
1065:I²C
1000:HIL
985:DCB
956:or
943:SSA
926:SAS
886:SMD
881:IPI
803:AGP
793:PXI
783:PCI
778:UPA
758:VLB
748:MCA
733:VPX
728:VXS
723:VXI
718:VME
703:LPC
673:ISA
405:).
391:PAM
387:PSM
358:or
344:USB
253:PCI
245:ATA
241:ISA
193:RAM
129:In
45:by
1271::
1075:,
1071:,
493:).
479:.
389:,
375:RF
346:,
259:/
251:,
247:,
243:,
208:,
149:.
133:,
1227:)
1223:(
1079:)
1067:(
521:e
514:t
507:v
453:.
303:.
278:)
112:)
106:(
101:)
97:(
87:·
80:·
73:·
66:·
39:.
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