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Bus systems

NameMultidropMax nodesElectrical typeCable typeMax bitrate [kbit/s]Length at max bitrateMax length [m]Bitrate at max length
EIA-485 (UART based)Y256EIA-485Twisted pair1000 kbit/s1330 m64 kbit/s
SCSI-1/2Y8Open collectorRibbon cable20 000 kbit/s3 m6 m5 Mbit/s/ch
SCSI Ultra2Y16EIA-485Twisted pair40 000 kbit/s12 m
LINY16Open collectoropen collector with pull-up to 12V car supply19.2 kbit/s40 m
SIOXY6219.2 kbit/s
I²CY127 or 1023Open collector5000 kbit/s7.6 m
SMBusY128Open collector100 kbit/s
PMBusY128Open collector400 kbit/s
10Base-2Y30DifferentialRG58 coaxial10 000 kbit/s185 m185 m
CANY128ISO 11898-2 DifferentialTwisted pair1000 kbit/s40 m1000 m50 kbit/s
DMX512-AN32EIA-485Twisted pair 120 Ω250 kbit/s548 m548 m (1800ft.)[4]250 kbit/s
DCCY127Single ended5 kbit/s
RS-232N2Single ended128 kbit/s1.5 m (approx)15 m19.6 kbit/s
PSI5YTwisted pair189 kbit/s12 m (approx)
1-WireY248Open collectorSingle conductor, with ground16.3 kbit/s300 m
X10Y256Power line0.05 kbit/s / 0.06 kbit/s
FlexRayTwisted pair20 000 kbit/s
SENTN2Single endedSingle conductor, with 5 V power supply and groundasync. transmission, min. 39.216 kbits/s5 m
SPCY5Single ended or Open collectorSingle conductor, with 5 V power supply and ground, shielded when using higher speedssync. and async. transmission, variable up to ~150 kbit/s~0.5 m5 msame as SENT
I3CY12712 500 kbits/s
SPIYvariable up to ~10000 kbit/s

The number of nodes can be limited by either number of available Network address|addresses or bus capacitance. None of the above use any analog domain modulation techniques like MLT-3 encoding, Pulse-amplitude modulation|PAM-5 etc. PSI5 designed with automation applications in mind is a bit unusual in that it uses Manchester code.

Bus Systems