Wilamowski B.M., Irwin J.D. The Industrial Electronics Handbook. Second Edition: Industrial Communication Systems

Подождите немного. Документ загружается.

Ethernet POWERLINK 39-11

. 5.. e.IAONA.Industrial.Ethernet.Planning.and.Installation.Guide,.IAONA.Guide..[Online]:.http://

www.iaona-eu.com/home/downloads.php

. 6.. Eth

ernet

.POWERLINK.Comm

unication

.Pro

le

.Spe

cication

.V.1.1.0,.EPSG.Dra.Std.301..[Online]:.

htt

p://www.ethernet-powerlink.org,

.2008.

. 7.. IEC

61784

. Int

ernational

. Sta

ndard:

. Dig

ital

. dat

. com

munications

. for. mea

surement

. and. con

trol.

Par

.1:.Pro

le

.set

.for.con

tinuous

.and.dis

crete

.man

ufacturing

.rel

ative

.to.el

dbus

.use.in.ind

ustrial

con

trol

.syst

ems.

.Par

.2:.Add

itional

.pro

les

.for.ISO

/IEC8802-3

.bas

.com

munication

.net

works

.in.

rea

l-time

.app

lications,

.Int

ernational

.Ele

ctrotechnical

.Com

mission

.Std

.Nov

ember

.200

. 8.. IEEE.802.3.Sta

ndard:

.Car

rier

.sens

.mul

tiple

.access.wit

.colli

sion

.detec

tion

.(CSMA/CD).access.

meth

.and.physic

.lay

.spe

cications,

.IEEE.Std

.Ins

titute

.of.Elec

trical

.and.Elec

tronics

.Engin

eers,

Inc.,.Oc

tober

.2000.

. 9.. F..Benzi,.G..Buj

.and.M..Fel

ser.

.Comm

unication

.arc

hitectures

.for.elec

trical

.driv

es.

.IEEE Tr

ansactions

on Industrial Informatics,

.1(1):47–53,.Fe

bruary

.2005.

. 10.. CAN.In.Aut

omation,

.Int

ernational

.User

.and.Man

ufacturers

.Gro

.e.V..Std

.CANop

.App

lication

Lay

.an

.Co

mmunication

.Pr

ole,

.CiA/DS301,.Ver

sion

.4.01,.Jun

.2000.

. 11.. Eth

ernet

.POWERLINK.Sta

ndardization

.Gro

up.

.Eth

ernet

.POWERLINK.Comm

unication

.Pro

le

Spe

cication

.V.0.1.0,.EPSG.Dra.St

.[Onlin

e]:

.ht

tp://www.ethernet-powerlink.org,

.2003.

. 12.. Eth

ernet

.POW

ERLINK

.Sta

ndardization

.Gro

up.

.Hig

.Ava

ilability

.Ser

vice

.Spe

cication

.Part.A.V1.

0.0,

EPS

.Dra



.Sta

ndard

.302

.[On

line]:

.htt

p://www.iaona-eu.com/home/downloads.php,

.200

. 13.. S..Vitturi.and.L..Seno..A.simulation.study.of.Ethernet.powerlink.networks..IEEE Conference on

Emerging Technologies and Factory Automation,

.pp

.740–743,.Pa

tras,

.Gr

eece,

.Sep

tember

.2007.

. 14.. A.. Pfei

er.

. Eth

ernet

. pow

erlink:

. Rea

l-time

. indu

strial

. ether

net

. is. rea

. [Online]:. htt

p://www.ict.

tuwien.ac.at/wfcs2004,

.Wor

kshop on Factory Communication Systems, WFCS 2004 Industry Day,

Vienna,.Au

stria,

.Sep

tember

.22–24,.2004.

. 15.. R..Zuraws

ky.

.Ind

ustrial

.communic

ation

.system

.e I

ndustrial Information Technology Handbook,

CRC.Pr

ess,

.Bo

.Ra

ton,

.FL,.pp

.37.1–47.16,.2005.

40-1

40.1 Introduction

PROFINET.is.the.real-time.(RT).Ethernet.solution.developed.by.PROFIBUS.International.(PI),.the.world.

assoc

iation

.of.PROF

IBUS

.and.PROF

INET

.manu

facturers

.and.users

. e.PROF

INET

.prot

ocol

.is.an.inte

national

.stan

dard

.sinc

.it.has.been.inco

rporated

.in.the.curr

ent

.editi

.of.the.IEC.6115

.and.IEC.6178

stan

dards.

.In.deta

ils,

.the.IEC6

1784

.den

.the.subse

.of.the.servi

ces

.speci

ed

.in.IEC.6115

.that.are.to.be.

appl

ied

.for.PROF

INET

.unde

.the.desi

gnation

.“Fam

ily

.3”.with.subd

ivisions

.3/3,.3/4,.3/5,.and.3/6.

rom

.the.abst

ract

.poin

.of.view

.the.PROF

INET

.conc

ept

.is.a.modu

lar

.conc

ept

.that.allo

.the.user.to.

choo

.the.func

tionality

.he.requ

ires.

.Gene

rally,

.the.func

tionality

.die

.main

.in.term

.of.the.type.of.

data.exch

ange;

.for.inst

ance,

.some.appl

ications

.have.very.stri

ngent

.requ

irements

.for.data.tran

smission

spee

.whi

.oth

.app

lications

.nee

.dat

.ref

resh

.cyc

les

.of.ten

.of.mil

liseconds.

.deve

lopment

.of. PROF

INET

.star

ted

.in. 2000

. e. rst. rele

ased

.spec

ications

.desc

ribed

.the.

so-c

alled

.PROF

INET CBA

.(com

ponent-based

.autom

ation)

.proto

col.

.PROF

INET

.CBA.is.suit

able

.for.

comp

onent-based

.mach

ine-to-machine

.comm

unication

.via.TCP/

.and.objec

t-oriented

.prog

ramming.

It.enab

les

.a.simpl

.modu

lar

.desig

.of.plan

.and.prod

uction

.line

.base

.on.dist

ributed

.inte

lligence

.using.

grap

hics-based

.con

guration

.of.comm

unication

.betw

een

.inte

lligent

.modu

les.

. e.basic.idea.behi

CBA.is.that.whol

.autom

ation

.syst

ems

.can.oen.be.grou

ped

.into.auton

omously

.oper

ating

.unit

. e.

stru

cture

.and.func

tionality

.can.be.repe

ated

.in.iden

tical,

.or.slig

htly

.modi

ed,

.form.in.mult

iple

.plan

ts.

 ese.so-c

alled

.PROF

INET

.CBA.comp

onents

.are.gene

rally

.cont

rolled

.by.an.easil

.iden

tied

.set.of.inpu

signa

ls.

.Withi

.the.comp

onent,

.a.cont

rol

.prog

ram

.writ

ten

.by.the.user.exec

utes

.the.requ

ired

.func

tion-

ality

.of.the.comp

onent

.and.send

.the.corr

esponding

.outp

.sign

als

.to.anot

her

.cont

roller.

 ank

PROFINET

40.1. Introduction.....................................................................................40-1

Device.Classes.in.PROFINET.IO. •. Performance. •. Conformance.

Classes. •. Prerequisites

40.2. PROFINET.IO.Basics......................................................................40-5

Device.Model. •. Address.Resolution. •. Cyclic.Data.

Trac. •. AcyclicData.Trac. •. Diagnostics

40.3. IRT.Communication.in.PROFINET.IO.......................................40-8

Flexible.Communication.Based.on.RT_CLASS_2.

(OrangeInterval). •. Communication.Based.on.RT_CLASS_3.

(RedInterval). •. Cycle.Duration.and.Constrains

40.4. Engineering.and.Commissioning...............................................40-11

GSD.File. •. Device.Addressing. •. System.Power-Up. •. .

Neighborhoodand.Topology.Detection. •. Redundancy

40.5. Integration.of.Fieldbus.Systems.and.Web.Applications..........40-14

Integration.via.Proxy. •. Web.Integration

Acronyms...................................................................................................40-15

Bibliography...............................................................................................40-15

Max Felser

Bern University of

Appl

ied

Sci

ences

Paolo Ferrari

University of Brescia

Alessandra

Flammini

University of Brescia

40-2 Industrial Communication Systems

its.component-based.architecture,.the.communication.in.PROFINET.CBA.is.congured.rather.than.

programmed..On.the.other.hand,.the.communication.with.PROFINET.CBA.oers.bus.cycle.times.

of.approximately.50–100.ms.(when.the.sole.TCP/IP.services.are.used),.roughly.compatible.with.RT.

requirements.in.modular.plant.manufacturing..Faster.bus.cycles.(on.the.order.of.milliseconds).are.pos-

sible

.if.an.additional.data-exchange.modality.that.also.uses.Ethernet.frames.is.activated.

.more.recent.version.of.the.PROFINET.specications.introduced.PROFINET IO.(input.output).in.

order.to.deal.with.the.more-demanding.distributed.I/O..PROFINET.IO.features.RT.communication.(best.

eort.paradigm).and.isochronous.real-time.(IRT).communication.(reserved.band.and.time.paradigm).

with.the.distributed.I/O.. e.designations.RT.and.IRT.are.used.solely.to.describe.the.RT.properties.of.

communication. within.PROFINET.IO;.the.user.can. scale.the.performance.following.the.application.

requirements..PROFINET.IO.describes.the.overall.data.exchange.between.controllers.and.devices.as.well.

as.the.parameterization.and.diagnostic.options.. e.bus.cycle.times.for.the.data.exchange.are.much.faster.

than.in.PROFINET.CBA,.e.g.,.cycle.time.in.the.order.of.few.hundred.microseconds.is.possible.

.the.following.of.this.chapter,.PROFINET.IO.will.be.discussed.in.details,.since.it.is.the.more.inno-

vating

.part.of.the.PROFINET.concept..Currently,.PRONIFET.CBA.is.diused.and.used.mainly.in.the.

North.American.market,.while.it.is.not.well.established.in.Europe.and.other.continents..On.the.con-

trary,

.PROFINET.CBA.is.the.optimal.solution.for.plant.supervising.and.control..PROFINET.CBA.and.

PROFINET.IO.can.be.operated.separately.and.in.combination.such.that.a.PROFINET.IO.plant.appears.

in.the.plant.view.as.a.PROFINET.CBA.unit.

40.1.1 Device Classes in PrOFINEt IO

PROFINET.follows.the.provider/consumer.model.for.data.exchange.. e.provider.(i.e.,.the.source.of.data.

as.dened.by.IEC.Standard),.usually.the.eld.device.at.the.process.level,.provides.process.data.to.a.con-

sumer

.(normally.a.PLC.with.a.processing.program)..In.principle,.a.PROFINET.IO.eld.device.can.contain.

any.arrangement.of.provider/consumer.functions..Figure.40.1.presents.the.device.classes.(IO.controller,.

IO.supervisor,.IO.device).and.the.communication.services.. e.following.devices.classes.are.dened.to.

facilitate.structuring.of.PROFINET.IO.eld.devices:

IO Controller:

. is.is.typically.the.programmable.logic.controller.(PLC).on.which.the.automation.pro-

gram

.runs.(corresponds.to.the.functionality.of.a.class.1.master.in.PROFIBUS).

IO Supervisor

.(e.g.,.engineering.station):. is.can.be.a.programming.device.(PG),.personal.computer.

(PC),.or.human.machine.interface.(HMI).device.for.commissioning.or.diagnostic.purposes.

IO Device:

.An.IO.device.is.a.distributed.I/O.eld.device.that.is.connected.via.PROFINET.IO.(corre-

sponds

.to.the.function.of.a.slave.in.PROFIBUS).

Ethernet

PROFINET IO-controller

Example:

A PLC that accesses

the process signal

through the process

image

PROFINET IO-supervisor

Example:

A eld device that

read and write I/O

PROFINET IO-device

Example:

A system used for

diagnosis and

commissioning

- Diagnosis

- Parametrization

- Status/control

- Conguration

- Process data

- Alarms

- Diagnosis

- Up-download

IO-C

IO-S

IO-D

FIGURE 40.1 Device.classes.and.their.relations.

PROFINET 40-3

A.plant.unit.contains.at.least.one.IO.controller.and.one.or.more.IO.devices..An.I/O.device.can.

exc

hange

.dat

.wit

.mul

tiple

.I/O.con

trollers.

.IO.sup

ervisors

.are.usu

ally

.int

egrated

.onl

.tem

porarily

.for.

com

missioning

.or.tr

oubleshooting

.pu

rposes.

40.1.2 Performance

RT.communication.constitutes.the.basis.for.data.exchange.in.PROFINET.IO..RT.data.are.handled.with.

hig

her

.pri

ority

.com

pared

.to.TCP.(UD

P)/IP

.dat

. is.met

hod

.of.dat

.exc

hange

.all

ows

.bus.cyc

.tim

in.th

.ra

nge

.of.a.fe

.te

.of.mi

lliseconds

.to.be.ac

hieved.

Standard

.Ethe

rnet

.com

munication

.via.TCP.(UD

P)/IP

.com

munication

.is.su

cient

.for.dat

.com

mu-

nication

.in.som

.cas

es.

.In.ind

ustrial

.auto

mation,

.how

ever,

.req

uirements

.reg

arding

.tim

.beh

avior

.and.

iso

chronous

.op

eration

.ex

ist

.th

.ca

nnot

.be.fu

lly

.sa

tised

.usi

.th

.UD

P/IP

.ch

annel.

For

.the

.rea

sons,

.PRO

FINET

.IO.ado

pts

.a.scal

able

.RT.app

roach.

.A.PRO

FINET

.IO.sys

tem

.wit

.RT.

can.be.rea

lized

.wit

.sta

ndard

.net

work

.com

ponents,

.suc

.as.swi

tches

.and.sta

ndard

.Eth

ernet

.con

trollers.

RT.com

munication

.tak

.pla

.wit

hout

.TCP

/IP

.inf

ormation,

.i.e.

.the.tra

nsmission

.of.RT.dat

.is.based.on.

cyc

lical

.dat

.exc

hange

.usi

.a.pro

vider/consumer

.mod

.and.bes

.eo

.par

adigm.

. e.com

munication

mech

anisms

.of.lay

.2.(acc

ording

.to.the.ISO

/OSI

.mod

el)

.are.su

cient

.for.thi

.For.opt

imal

.pro

cessing

.of.

RT.fra

mes

.wit

hin

.an.IO.dev

ice,

.the.VLA

.tag.acco

rding

.to.IEE

.802

.1Q

.(pr

ioritization

.of.dat

.fra

mes)

.has.

bee

.sup

plemented

.wit

.a.spec

ial

.Eth

ertype

.tha

.ena

bles

.fas

.cha

nnelization

.of.the

.PRO

FINET

.fra

mes

.in.

the.hig

her

.lev

.sow

are

.of.the.el

.dev

ice.

.Eth

ertypes

.are.all

ocated

.by.IEE

.and.are

.the

refore,

.an.una

biguous

.cri

terion

.for.di

erentiation

.amo

.Eth

ernet

.pro

tocols.

.Eth

ertype

.0x8

892

.is.spec

ied

.in.IEE

.and.

is.used.for.fas

.dat

.exc

hange

.in.PRO

FINET

.IO.

sochronous

.dat

.exc

hange

.wit

.PRO

FINET

.is.de

ned

.in.the.IRT.con

cept.

.Dat

.exc

hange

.cyc

les

are.nor

mally

.in.the.ran

.of.a.few.hun

dred

.mic

roseconds

.to.1.ms..IRT.com

munication

.di

ers

.fro

.RT.

com

munication

.mai

nly

.in.its.iso

chronous

.beh

avior,

.mea

ning

.tha

.the.bus.cyc

les

.are.sta

rted

.wit

.max

mum

.precision..For.example,.the.start.of.a.bus.cycle.can.deviate.by.a.maximum.of.1.μs..IRT.is.required.

in.mo

tion

.co

ntrol

.ap

plications

.(p

ositioning

.op

erations).

.ena

ble

.enh

anced

.sca

ling

.of.com

munication

.opti

ons

.and

.thu

.als

.of.det

erminism

.in.PRO

FINET

IO,.RT.cla

sses

.hav

.bee

.de

ned

.for.dat

.exc

hange.

.Fro

.the.use

.per

spective,

.the

.cla

sses

.inv

olve

uns

ynchronized

.and.syn

chronized

.com

munication.

. e.det

ails

.are.man

aged

.by.the.el

.dev

ices

.the

selves.

.RT.fra

mes

.are.auto

matically

.pri

oritized

.in.PRO

FINET

.com

pared

.to. UDP

/IP

.fra

mes.

. is.is.

nec

essary

.in.ord

.to.pri

oritize

.the.tra

nsmission

.of.dat

.in.swi

tches

.to.pre

vent

.RT.fra

mes

.fro

.bei

del

ayed

.by.UDP

/IP

.fra

mes.

.PRO

FINET

.IO.di

erentiates

.the.fol

lowing

.cla

sses

.for.RT.com

munication.

 ey.di

er

.no

.in.te

rms

.of.pe

rformance

.bu

.in.de

terminism.

RT_CLASS_1:

.Uns

ynchronized

.RT.com

munication

.wit

hin

.a.sub

net.

.No.spe

cial

.add

ressing

.inf

ormation

is.req

uired

.for.thi

.com

munication.

. e.des

tination

.nod

.is.ide

ntied

.usin

.the.“de

stination

.add

ress”

onl

.Uns

ynchronized

.RT.com

munication

.wit

hin

.a.sub

net

.is.the.usu

.dat

.tra

nsmission

.met

hod

.in.

PRO

FINET

.IO..If.the.RT.dat

.tra

c

.has.bee

.res

tricted

.to.one.sub

net

.(sa

.net

work

.ID)

.thi

.var

iant

is.the.simp

lest.

. is.com

munication

.pat

.is.sta

ndardized

.in.par

allel

.to.UDP

/IP

.com

munication

.and.

imp

lemented

.in.eac

.IO.el

.dev

ice.

.A.del

iberate

.dec

ision

.was.mad

.her

.to.eli

minate

.the.man

agement

inf

ormation

.of.UDP

/IP

.and.RPC

. e.RT.fra

mes

.rec

eived

.are.alr

eady

.ide

ntied

.upo

.rec

eipt

.usin

.the.

Ethe

rtype

.(0x

8892)

.and.for

warded

.to.the.RT.cha

nnel

.for.imm

ediate

.pro

cessing.

.Any.(in

dustrial-grade)

sta

ndard

.sw

itch

.ca

.be.us

.in.th

.RT.cl

ass.

RT_CLASS_2:

. Fra

mes

. can. be. tra

nsmitted

. via. syn

chronized

. or. uns

ynchronized

. com

munication.

Uns

ynchronized

.com

munication

.in.thi

.cas

.can.be.vie

wed

.exa

ctly

.the.sam

.as.RT_

CLASS_1

.com

munication.

.In.syn

chronized

.com

munication,

.the.sta

.of.a.bus.cyc

.is.de

ned

.for.all.nod

es.

. is.spe

ci-

es

.exa

ctly

.the.all

owable

.tim

.bas

.for.el

.dev

ice

.tra

nsmission.

.For.all.el

.dev

ices

.par

ticipating

.in.

RT_

CLASS_2

.com

munication,

.thi

.is.alw

ays

.the.sta

.of.the.bus.cyc

le.

. e.swi

tches

.use

.for.thi

.com

munication

.cla

.mus

.sup

port

.thi

.syn

chronization

.mec

hanism.

. is.typ

.of.dat

.tra

nsmission,

.whi

40-4 Industrial Communication Systems

has.been.designed.for.performance,.brings.with.it.specic.hardware.requirements.(Ethernet.controller/

switch

.wi

.su

pport

.of.is

ochronous

.op

eration).

RT_CLASS_3:

. Syn

chronized

. com

munication

. wit

hin

. a. sub

net.

. Dur

ing

. syn

chronized

. RT_

CLASS_3

com

munication,

.pro

cess

.dat

.are.tra

nsmitted

.wit

.max

imum

.pre

cision

.in.an.exa

.ord

.spe

cied

.dur

ing

.sys

tem

.eng

ineering

.(ma

ximum

.all

owable

.dev

iation

.fro

.sta

.of.bus.cyc

.of.1.μs)..With.the.aid.of.

topo

logy-optimized

.dat

.tra

nsmission,

.thi

.is.als

.ref

erred

.to.as.IRT.fun

ctionality.

.In.RT_

CLASS_3

com

munication,

.the

.are.no.wai

.tim

es.

.In.ord

.to.tak

.adv

antage

.of.the.dat

.tra

nsmission

.desi

gned

for.max

imum

.per

formance,

.spe

cial

.har

dware

.req

uirements

.app

.(Eth

ernet

.con

troller

.wit

.sup

port

.of.

iso

chronous

.op

eration).

RT_CLASS_UDP:

. e.unsynchronized.cross-subnet.communication.between.dierent.subnets.requires.

add

ressing

.inf

ormation

.via.the.des

tination

.net

work

.(IP.add

ress).

. is.var

iant

.is.als

.ref

erred

.to.as.RT_

LASS_UDP.

.Sta

ndard

.sw

itches

.ca

.be.us

.in.th

.RT.cl

ass.

For

.RT.fra

mes,

.dat

.cyc

les

.of.5.ms.at.100.Mbp

.in.ful

l-duplex

.mod

.wit

.VLA

.tag.are.su

cient.

. is.

RT.co

mmunication

.ca

.be.re

alized

.wi

.al

.av

ailable

.st

andard

.ne

twork

.co

mponents.

40.1.3 Conformance Classes

Since.the.complete.scope.of.functions.implemented.in.PROFINET.IO.is.not.required.in.every.automa-

tion

.sys

tem,

.the.con

formance

.cla

sses/application

.cla

sses

.are.int

roduced.

. e.obje

ctive

.is.to.simp

lify

.the.

app

lication

.are

.of.PRO

FINET

.IO.. e.res

ulting

.app

lication

.cla

sses

.ena

ble

.pla

.ope

rators

.to.easi

sel

ect

.el

.dev

ices

.and.bus.com

ponents

.wit

.exp

licitly

.de

ned

.min

imum

.pro

perties.

. e.min

imum

req

uirements

.for.thr

.con

formance

.cla

sses

.(CC

-A,

.CC-

.hav

.bee

.de

ned

.fro

.the.per

spec-

tive

.of.the.pla

.ope

rator.

.In.add

ition

.to.the.thr

.app

lication

.cla

sses,

.add

itional

.spe

cications

.hav

.bee

mad

.for.dev

ice

.typ

es,

.typ

.of.com

munication,

.tra

nsmission

.med

ium

.use

.and.red

undancy

.beh

avior.

 is.spe

cication

.ens

ures

.the.int

eroperability

.in.an.auto

mation

.sys

tem

.wit

.reg

ard

.to.the.sco

.of.fun

tions

.and.per

formance

.par

ameters.

.It.is.ass

ured

.tha

.all.el

.dev

ices

.wit

hin

.the.sel

ected

.CC.mee

.the.

sam

.mi

nimum

.re

quirements.

. e.ap

plication

.ar

eas

.cu

rrently

.ar

CC-A:

.Use.of.the.inf

rastructure

.of.an.exi

sting

.Ethe

rnet

.net

work

.inc

luding

.int

egration

.of.basi

PRO

FINET

.fun

ctionality.

.All.IT.ser

vices

.can.be.use

.wit

hout

.res

trictions.

.Exa

mples

.of.typ

ical

app

lications

.are.in.bui

lding

.auto

mation

.and.pro

cess

.auto

mation.

.Wire

less

.com

munication

.is.

onl

.po

ssible

.in.th

.cl

ass.

CC-B:

.In.add

ition

.to.the.fun

ctions

.of.CC-

.the.sco

.of.fun

ctions

.of.CC-

.sup

ports

.eas

.and.

use

r-friendly

.dev

ice

.rep

lacement

.wit

hout

.the.nee

.for.an.eng

ineering

.tool

.To.inc

rease

.the.dat

sec

urity,

.a.med

.red

undancy

.pro

tocol

.for.TCP.(UD

P)/IP

.dat

.is.int

egrated.

.Exa

mples

.of.typ

cal

.app

lications

.are.in.auto

mation

.sys

tems

.wit

.a.hig

her-level

.mac

hine

.con

troller

.tha

.pla

rel

atively

.lo

.de

mands

.fo

.a.de

terministic

.da

.cy

cle.

CC-C:

.In.add

ition

.to.the.fun

ctions

.of.CC-

.the.sco

.of.fun

ctions

.of.CC-

.sup

ports

.hig

precision

.and.det

erministic

.dat

.tra

nsmission,

.inc

luding

.for.iso

chronous

.app

lications.

. e.

int

egrated

. med

. red

undancy

. ena

bles

. smo

oth

. swi

tchover

. of. the. I/O. dat

. tra

c

. if. a. fau

occ

urs.

.An.ex

ample

.of.a.ty

pical

.ap

plication

.is.th

.e

.of.mo

tion

.co

ntrol.

40.1.4 Prerequisites

PROFINET.IO.eld.devices.are.addressed.using.MAC.addresses.and.IP.addresses..Each.subnet.is.rep-

resented

.by.a.di

erent

.net

work_ID

.(su

bnet

.mas

k).

.PRO

FINET

.IO.el

.dev

ices

.are.alw

ays

.con

nected

as.net

work

.com

ponents

.via.swi

tches.

. is.tak

.the.for

.of.a.sta

.topo

logy

.wit

.sep

arate

.mul

tiport

PROFINET 40-5

switches.or.a.line.topology.with.switches.integrated.in.the.eld.device.(two.ports.occupied)..Within.a.

network,.a.PROFINET.IO.eld.device.is.addressed.by.its.device.MAC.address.

PROFINET

.transmits.some.message.frames.(e.g.,.for.synchronization,.neighborhood.detection).

with.the.MAC.address.for.the.respective.port.and.not.the.device.MAC.address..For.this.reason,.each.

switch.port.in.a.eld.device.requires.a.separate.port.MAC.address.. erefore,.a.two-port.eld.device.

has.three.MAC.addresses.in.the.as-delivered.condition..However,.these.port.MAC.addresses.are.not.

visible.to.users..Because.the.eld.devices.are.connected.via.switches,.PROFINET.always.sees.only.

point-to-point.connections.(same.as.Ethernet).. at.is,.if.the.connection.between.two.eld.devices.in.

a.line.is.interrupted,.the.eld.devices.located.aer.the.interruption.are.no.longer.accessible..If.increased.

availability.is.required,.provision. must.be.made.for.redundant.communication.paths. when.plan-

ning

.the.system,.and.eld.devices/switches.that.support.the.redundancy.concept.of.PROFINET.must.

be.used..Any.switch.that.supports.“autonegotiation”.(negotiating.of.transmission.parameters).and.

“autocrossover”.(crossing.of.send.and.receive.lines.in.the.switch).is.suitable.for.PROFINET.IO.RT.

communication..On.the.other.hand,.IRT.communication.requires.switch.with.embedded.synchro-

nization

.capabilities.and.PROFINET.frame.managing..Any.Ethernet.cable.is.suitable.for.PROFINET.

applications. from. the. electrical.point.of. view;.however,. further.requirements. due. to. the. factory/

industry

.environment.could.apply.

40.2 PrOFINEt IO Basics

PROFINET.IO.protocol.provides.denitions.for.the.following.services:.device.model;.address.resolu-

tion

.for.eld.devices;.cyclic.transmission.of.I/O.data.(RT.and.IRT);.acyclic.transmission.of.alarms.to.

be.acknowledged;.cyclic.transmission.of.data.(parameters,.detailed.diagnostics,.I&M.data,.information.

functions,.etc.).on.an.as.needed.basis;.redundancy.mode.for.RT.frames.

.combination.of.these.communication.services.in.the.higher.level.controller.makes.it.possible.to.

implement.convenient.system.diagnostics,.topology.detection,.and.device.replacement.

40.2.1 Device Model

 e.overview.of.the.device.modeling,.given.in.Figure.40.2,.is.advantageous.to.facilitate.understanding.of.

process.data.addressing.in.a.PROFINET.IO.eld.device..For.eld.devices,.a.distinction.is.made.between.

compact eld devices.(the.degree.of.expansion.is.dened.in.the.as-delivered.condition.and.cannot.be.

Slot 0 and

Subslot 0 = DAP

Subslot 1 …

0x7FFF

Index 1 … X

Slot 2 and

Subslot 0

Slot

Subslot 1

Index 1 … X

Subslot 2

Index 1 … X

Subslot … 0×7FFF

Slot 2 and

Subslot 0

Slot

Subslot … 0×7FFF

Slot 0×7FFF and

Subslot 0

Slot

Subslot … 0×7FFF

Slot 1 Slot … Slot 0×7FFF

DAP I/O module I/O module I/O module

…

Slot 0

FIGURE 40.2 I/O.data.are.addressed.in.PROFINET.on.the.basis.of.slots.and.subslots.

40-6 Industrial Communication Systems

changed.to.meet.future.requirements).and.modular eld devices.(for.dierent.applications,.the.degree.of.

exp

ansion

.ca

.be.cu

stomized

.to.th

.us

.ca

.wh

.co

nguring

.th

.sy

stem).

All

.el

.dev

ices

.are.des

cribed

.in.ter

.of.the

.ava

ilable

.tec

hnical

.and.fun

ctional

.pro

perties

.in.a.gen

eral

.sta

tion

.des

cription

.(GS

.le.to.be.cre

ated

.by.the.el

.dev

ice

.dev

eloper.

.It.con

tains,

.amo

.oth

thi

ngs,

.a.rep

resentation

.of.the.dev

ice

.mod

.tha

.is.rep

roduced

.by.the.dev

ice

.acc

ess

.poi

.(DA

.and.

the.de

ned

.mod

ules

.for.a.par

ticular

.dev

ice

.fam

ily.

.A.DAP.is,.so.to.spe

ak,

.the.bus.int

erface

.(ac

cess

.poi

for.com

munication)

.to.the.Ethe

rnet

.int

erface

.and.the.pro

cessing

.pro

gram.

.It.is.de

ned

.alo

.wit

.its.

pro

perties

.and.ava

ilable

.opti

ons

.in.the.GSD.le

.A.var

iety

.of.I/O.mod

ules

.can.be.assi

gned

.to.it.in.ord

to.ma

nage

.th

.ac

tual

.pr

ocess

.da

.tr

ac.

.slo

.desi

gnates

.the.phy

sical

.slo

.of.an.I/O.mod

ule

.in.a.mod

ular

.I/O.el

.dev

ice

.in.whi

.a.mod

ule

des

cribed

.in.the.GSD.le.is.pla

ced.

.With

.a.slo

.the.sub

slots

.for

.the.act

ual

.int

erface

.to.the.pro

cess

(in

puts/outputs).

. e.gra

nularity

.of.a.sub

slot

.(bi

twise,

.byt

ewise,

.or.wor

dwise

.div

ision

.of.I/O.dat

.is.

det

ermined

.by.the.man

ufacturer.

. e.dat

.con

tent

.of.a.sub

slot

.is.alw

ays

.acc

ompanied

.by.sta

tus

.inf

orma-

tion,

.fr

.wh

ich

.th

.va

lidity

.of.th

.da

.ca

.be.de

rived.

.ind

.spe

cies

.the.dat

.wit

hin

.a.slo

t/subslot

.tha

.can.be.rea

.or.wri

tten

.acy

clically

.via.rea

d/write

ser

vices.

.For.exa

mple,

.par

ameters

.can.be.wri

tten

.to.a.mod

ule

.or.man

ufacturer-specic

.mod

ule

.dat

.can.

be.rea

.out.on.the.basi

.of.an.ind

ex.

.Cyc

lic

.I/O.dat

.are.add

ressed

.by.spe

cifying

.the.slo

t/subslot

.comb

nation.

. e

.ca

.be.fr

eely

.de

ned

.by.th

.ma

nufacturer.

For

.acy

clic

.dat

.tra

c

.via.rea

d/write

.ser

vices,

.an.app

lication

.can.spe

cify

.the.exa

.dat

.to.be.add

ressed

using.slot.and.subslot..For.demand-oriented.data.exchange,.the.third.addressing.level,.i.e.,.the.index.is.

add

ed.

. e.ind

.de

nes

.the.fun

ction

.tha

.is.to.be.ini

tiated

.via.the.slo

t/subslot

.comb

ination

.(e.

g.,

.rea

ing

.of.in

put

.da

.of.a.su

bslot,

.re

ading

.of.I&

.fu

nctions,

.an

.re

ading

.of.ac

tual/desired

.co

nguration).

40.2.2 address resolution

For.PROFINET.IO.eld.devices,.address.resolution.is.based.on.the.symbolic.name.of.the.device,.to.

whi

.a.un

ique

.MA

.ad

dress

.is.as

signed.

Aer

.the.sys

tem

.is.con

gured,

.the.eng

ineering

.tool.loa

.all.inf

ormation

.req

uired

.for.dat

.exc

hange

to.the.IO.con

troller,

.inc

luding

.the.IP.add

resses

.of.the.con

nected

.IO.dev

ices.

.Bas

.on.the.nam

.(an

the.ass

ociated

.MAC.add

ress),

.an.IO.con

troller

.can.rec

ognize

.the.con

gured

.el

.dev

ices

.and.assi

the

.the.spe

cied

.IP.add

resses

.usin

.the.dis

covery

.and.con

guration

.pro

tocol

.(DC

.int

egrated

.in.

PRO

FINET

.IO..Alt

ernatively,

.add

ressing

.can.be.per

formed

.via.a.dyn

amic

.hos

.con

guration

.pro

tocol

(DH

CP)

.ser

ver.

.Fol

lowing

.add

ress

.res

olution,

.the.sys

tem

.pow

ers

.up.and.par

ameters

.are.tra

nsmitted

.to.

the.IO.de

vices.

. e.sy

stem

.is.th

.av

ailable

.fo

.pr

oductive

.da

.tr

ac.

40.2.3 Cyclic Data traffic

Cyclic.I/O.data. are. transmitted. unacknowledged. as.RT. data. between. provider. and. consumer. in.a.

par

ameterizable

.res

olution.

. ey.are.org

anized

.into.ind

ividual

.I/O.ele

ments

.(su

bslots).

. e.con

nection

is.mon

itored

.usin

.a.wat

chdog

.(ti

.mon

itoring

.mec

hanism).

.Dur

ing

.dat

.tra

nsmission

.in.the.fra

me,

the.dat

.of.a.sub

slot

.are.fol

lowed

.by.a.pro

vider

.sta

tus.

. is.sta

tus

.inf

ormation

.is.eva

luated

.by.the.res

pec-

tive

.con

sumer

.of.the.I/O.dat

.It.can.use.thi

.inf

ormation

.to.eva

luate

.the.val

idity

.of.the.dat

.fro

.the.

cyc

lic

.dat

.exc

hange

.alo

ne.

.In.add

ition,

.the.con

sumer

.sta

tuses

.for.the.cou

nter

.dir

ection

.are.tra

nsmitted.

Dia

gnostics

.ar

.no.lo

nger

.di

rectly

.re

quired

.fo

.th

.pu

rpose.

For

.eac

.mes

sage

.fra

me,

.the.“da

.uni

t”

.(tr

ailer)

.is.fol

lowed

.by.acc

ompanying

.inf

ormation

.reg

ard-

ing

.the.glo

bal

.val

idity

.of.dat

.red

undancy,

.and.the.dia

gnostic

.sta

tus

.eva

luation

.(da

.sta

tus,

.tra

nsfer

sta

tus).

. e.cyc

.inf

ormation

.(cy

cle

.cou

nter)

.of.the.pro

vider

.is.als

.spe

cied

.so.tha

.its.upd

ate

.rat

.can.

be.det

ermined

.easi

ly.

.Fai

lure

.of.cyc

lic

.dat

.to.arr

ive

.is.mon

itored

.by.the.res

pective

.con

sumer

.in.the.

com

munication

.rel

ation.

.If.the.con

gured

.dat

.fai

.to.arr

ive

.wit

hin

.the.mon

itoring

.tim

.the.con

sumer

sen

.an.er

ror

.me

ssage

.to.th

.ap

plication.

PROFINET 40-7

For.data.exchange.with.multiple.parameters,.multicast.communication.relation.(MCR).has.been.

de

ned.

. is.all

ows

.dir

ect

.dat

.tra

c

.fro

.a.pro

vider

.to.mul

tiple

.nod

.(up.to.all.nod

es)

.as.dir

ect

.dat

exc

hange.

.MCR

.wit

hin

.a.seg

ment

.are.exc

hanged

.as.RT.fra

mes.

.Cro

ss-segment

.MCR.dat

.fol

low

.the.

dat

.ex

change

.of.th

.RT.cl

ass.

40.2.4 acyclic Data traffic

Acyclic.data.exchange.can.be.used.to.parameterize.and.congure.IO.devices.or.to.read.out.status.

inf

ormation.

. i

.is.ac

complished

.wi

.re

ad/write

.fr

ames

.vi

.st

andard

.IT.se

rvices

.usi

.UD

P/IP.

.add

ition

.to.the.dat

.rec

ords

.ava

ilable

.for.use.by.dev

ice

.man

ufacturers,

.the.fol

lowing

.sys

tem

.dat

rec

ords

.are.als

.spe

cially

.de

ned:

.dia

gnostic

.inf

ormation

.can.be.rea

.out.by.the.use

.fro

.any.dev

ice

at.any.tim

.err

.log.ent

ries

.(al

arms

.and.err

.mes

sages),

.whi

.can.be.use

.to.det

ermine

.det

ailed

tim

ing

.inf

ormation

.abo

.eve

nts

.wit

hin

.an.IO.dev

ice;

.ide

ntication

.inf

ormation

.as.spe

cied

.in.PI.

gui

deline

.“I&

.fun

ctions”;

.inf

ormation

.fun

ctions

.reg

arding

.rea

.and.log

ical

.mod

ule

.str

ucturing;

rea

dback

.of.I/O.dat

.in

dex

.is.us

.to.di

stinguish

.wh

ich

.se

rvice

.is.to.be.ex

ecuted

.wi

.th

.re

ad/write

.se

rvices.

.PRO

FINET

.IO,.the.tra

nsmission

.of.eve

nts

.is.mod

eled

.as.par

.of.the.ala

.con

cept.

. es

.inc

lude

bot

.sys

tem-dened

.eve

nts

.(su

.as.rem

oval

.and.ins

ertion

.of.mod

ules)

.and.use

r-dened

.eve

nts

.det

ected

in.the.con

trol

.sys

tems

.use

.(e.

g.,

.def

ective

.loa

.vol

tage)

.or.occ

urring

.in.the.pro

cess

.bei

.con

trolled

.(e.

g.,

tem

perature

.too.hig

h).

.Whe

.an.eve

.occ

urs,

.su

cient

.com

munication

.mem

ory

.mus

.be.ava

ilable

.for.

dat

.tra

nsmission

.to.ens

ure

.aga

inst

.dat

.los

.and.to.all

.the.ala

.mes

sage

.to.be.pas

sed

.qui

ckly

.fro

the.IO.dev

ice.

. e.app

lication

.in.the.dat

.sou

rce

.is.res

ponsible

.for.thi

.Ala

rms

.are.inc

luded

.in.acy

clic

RT.da

ta.

.abi

lity

.to.rea

.out.basi

.inf

ormation

.fro

.a.el

.dev

ice

.is.ver

.hel

pful

.in.man

.cas

es.

.For.exa

ple,

.thi

.all

ows

.inf

erences

.to.be.dra

.in.res

ponse

.to.inc

orrect

.beh

avior

.or.reg

arding

.uns

upported

fun

ctionality

.in.a.el

.dev

ice.

. er

efore,

.IO.dev

ices

.mus

.sup

ply

.at.lea

.the.fol

lowing

.dat

.ord

.ID,.

MAC.address,.hardware.revision,.soware.revision,.device.type,.vendor.ID,.all.I&M0.data.. ese.data.

are.nec

essary

.for.add

ressing

.the.el

.dev

ice

.as.wel

.as.for.rea

ding

.out.the.I&M.fun

ctions.

.(Not

.Eac

.IO.

dev

ice

.mu

.su

pport

.at.le

ast

.th

.IM

.fu

nction.)

40.2.5 Diagnostics

PROFINET.IO.transmits.high-priority.events.mainly.as.alarms.. ese.include.both.system-dened.

eve

nts

.(su

.as.rem

oval

.and.ins

ertion

.of.mod

ules)

.and.use

r-dened

.eve

nts

.(e.

g.,

.def

ective

.loa

.vol

age)

.det

ected

.in.the.con

trol

.sys

tems

.use

.or.occ

urring

.in.the.pro

cess

.(e.

g.,

.boi

ler

.pre

ssure

.too.hig

h).

Dia

gnostic

.and.sta

tus

.mes

sages

.rep

resent

.ano

ther

.mea

.of.for

warding

.inf

ormation

.reg

arding

.inc

orrect

beh

avior

.in.a.sys

tem.

. es

.are.not.tra

nsmitted

.act

ively

.to.the.hig

her

.lev

.con

troller.

.In.ord

.to.assi

the

.ex

plicitly,

.PR

OFINET

.di

stinguishes

.be

tween

.pr

ocess

.an

.di

agnostic

.al

arms.

Process alarms

.mus

.be.use

.if.the.mes

sage

.ori

ginates

.fro

.the.con

nected

.pro

cess,

.e.g

.a.lim

.tem

perature

.was.exc

eeded.

.In.thi

.cas

.the.IO.dev

ice

.may.sti

.be.ope

rable.

. e.dat

.are.not.sav

.loc

ally

in.th

.su

bmodule.

Diagnostic alarms

.mus

.be.use

.if.the.err

.or.eve

.occ

urs

.wit

hin

.an.IO.dev

ice

.(or.in.con

junction

wit

.the.con

nected

.com

ponents,

.suc

.as.a.wir

.bre

ak).

.Dia

gnostic

.and.pro

cess

.ala

rms

.can.be.pri

oritized

di

erently

.by.the.use

.In.con

trast

.to.pro

cess

.ala

rms,

.dia

gnostic

.ala

rms

.are.ide

ntied

.as.inc

oming

.or.

out

going.

For

. system. power-up,. the. IO. controller. transfers. the. connect. frame. containing. the.

“CM

InactivityTimeout-Factor,”

.whi

.is.use

.to.mon

itor

.the.sys

tem

.pow

er-up.

. is.mon

itoring

.tim

end

.ae

.the.rs

.val

.dat

.exc

hange

.bet

ween

.IO.con

troller

.and.IO.dev

ice

.and.is.the

.rep

laced

.by.

the.wat

chdog

.fun

ction.

.In.PRO

FINET

.IO.com

munication,

.the.cyc

lic

.dat

.tra

c

.bet

ween

.pro

vider

.and.

40-8 Industrial Communication Systems

consumer.is.monitored.by.the.watchdog.function,.which.is.integrated.by.default..Cyclic.data.including.

stat

.info

rmation

.are.tran

smitted

.betw

een

.the.IO.cont

roller

.and.IO.devi

ce.

.A.cons

umer

.dete

cts

.fail

ure

of.the.comm

unication

.conn

ection

.base

.on.expi

ration

.of.the.watc

hdog

.and.the.appl

ication

.in.the.con-

umer

.is.ther

eby

.info

rmed.

. e.resp

onse

.to.this.must.be.den

.on.a.user

-specic

.basis

. e.netw

ork

diag

nostics

.is.part.of.the.diag

nostics

.mana

gement

.and.cont

ributes

.signi

cantly

.to.the.reli

ability

.of.the.

netw

ork

.ope

ration.

For

.main

tenance

.purp

oses

.and.for.moni

toring

.the.netw

ork

.comp

onents,

.simpl

.netw

ork

.mana

ge-

ment

.proto

col

.(SNM

.has.been.esta

blished

.as.the.inte

rnational

.stan

dard.

.SNMP.allo

.both.read.

acce

.and.wri

.acc

ess

.(fo

.adm

inistration)

.of.net

work

.com

ponents

.in.ord

.to.rea

.out.sta

tistical

.dat

pert

aining

.to.the.netw

ork

.as.well.as.port

-specic

.data.and.info

rmation

.rega

rding

.the.neig

hborhood

dete

ction.

.In.PROF

INET,

.only.read.acce

.to.devi

.para

meters

.has.been.init

ially

.spec

ied.

.Like.the.

DHCP.of.IP.mana

gement,

.SNMP.will.also.be.optio

nal

.(man

datory

.for.conf

ormance

.clas

ses

.CC-B.and.

CC-C

.When.SNMP.is.impl

emented

.in.comp

onents,

.only.the.stan

dard

.info

rmation

.usua

.for.SNMP.

(MIB.2).is.acce

ssed.

.It.shou

.be.note

.that.SNMP.will.not.open.anot

her

.diag

nostic

.path.but.rath

enab

.inte

gration

.into.netw

ork

.mana

gement

.syst

ems

.that.gene

rally

.do.not.proc

ess

.PROF

INET-specic

info

rmation.

. e.SNMP.sow

are

.can.be.inte

grated

.in.the.PROF

INET

.stac

.at.the.user.leve

.and.used.

with

out

.rest

rictions.

.When.stan

dard

.swit

ches

.are.used

.the.swit

.dire

ctly

.forw

ards

.the.diag

nostic

info

rmation

.from.the.conn

ected

.PROF

INET

.devi

ces

.to.the.cont

roller.

.Howe

ver,

.a.swit

.can.also.be.

con

gured

.as.a.PROF

INET

.IO.devi

.and.rela

.the.dete

cted

.netw

ork

.erro

.of.a.lowe

.leve

.Ether

net

line.directly.to.the.controller.

40.3 Irt Communication in PrOFINEt IO

PROFINET.IO.provides.scalable.RT.classes.for.cyclic.transmission.of.process.data..In.addition.to.the.

requ

irements

.for.RT.capa

bility,

.ther

.are.also. proc

esses

.that. requ

ire

.isoc

hronous

.I/O.data.tran

sfer

(res

erved

.band.and.time.slot.para

digm).

.For.this.reas

on,

.sync

hronized

.PROF

INET

.comm

unication,

also.call

.IRT.comm

unication

.or.isoc

hronous

.comm

unication,

.was.intr

oduced.

.For.isoc

hronous

.data.

exch

ange,

.PROF

INET

.oer

.a.scal

able

.conc

ept

.that

.on.the.one.hand

.prov

ides

.a.very.exi

ble

.meth

of. comm

unication

. that. uses. the. sync

hronized

. RT_C

LASS_2

. comm

unication.

. On. the. othe

. hand

PROF

INET

.oer

.comm

unication

.desig

ned

.for.maxi

mum

.perf

ormance,

.whic

.requ

ires

.prec

ise

.plan

ning

.of.comm

unication

.path

.in.adva

nce.

. e.avai

lable

.band

width

.is.util

ized

.optim

ally

.in.this.case.

beca

use

.wait

ing

.time

.can.neve

.occu

.duri

.data.tran

smission.

. is.moda

lity

.uses.a.sync

hronized

RT_C

LASS_3

.comm

unication.

. e.comm

unication

.is.divi

ded

.into.a.rese

rved

.inte

rval

.and.an.open.

inte

rval.

.Only.the.time

-critical

.I/O.data.are.tran

sferred

.in.the.rese

rved

.inte

rval,

.whil

.all.othe

.data.are.

sent.in.the.open.phas

.No.addi

tional

.lowe

.leve

.proto

col

.is.requ

ired

.for.this

.All.eld.devi

ces

.part

ici-

pating

.in.IRT.comm

unication

.are.sync

hronized

.by.the.same.cloc

.mast

er,

.whic

.is.gene

rally

.inte

grated

in.the.IO.cont

roller.

.In.orde

.to.achi

eve

.bett

.sync

hronization,

.the.line

delay

.betw

een

.the.neig

hboring

node

.and.the.curr

ent

.sync

hronization

.is.also.dete

rmined.

.IRT.comm

unication

.is.base

.on.the.foll

ow-

ing

.con

ditions:

. 1.. e.comm

unication

.take

.plac

.excl

usively

.with

.one.subn

et,

.i.e.,.the.exis

ting

.addr

essing

.mech

anisms

.hav

.bee

.red

uced

.(al

.for.uns

ynchronized

.com

munication).

. 2.. e.bus.cycl

.is.divi

ded

.into.a.rese

rved

.IRT.phas

.and.an.open.phas

. ese.are.den

.as.foll

ows:

.the.“re

served

.int

erval”

.(IR

.pha

se),

.onl

.IRT.jobs.can.be.pro

cessed.

.the.“ope

.inte

rval,”

.job.proc

essing

.is.mana

ged

.acco

rding

.to.the.rule

.in.IEEE.802.(bas

.on.

prio

rities).

. 3..All.eld.devi

ces

.with

.an.IRT.doma

.must.supp

ort

.isoc

hronous

.oper

ation,

.even.if.the.appl

ica-

tion

.is.not.ope

rating

.syn

chronously.

PROFINET 40-9

 e.division.of.the.cycle.is.shown.in.Figure.40.3.

.following.intervals.are.dened.along.with.their.properties.in.PROFINET:

Red interval:

.Only.RT_CLASS_3.frames.may.be.forwarded.through.switches.in.this.interval.. e.forward-

ing

.rules.dened.in.IEEE.802.1D.do.not.apply.here..Instead,.the.forwarding.rules.dened.in.IEC.61158.

are.used.. e.start.time.of.the.red.interval.is.constantly.synchronized.. e.chronological.sequence.of.all.

RT_CLASS_3.frames.is.dened.during.engineering..If.UDP/IP.frames.arrive.or.are.generated.(because.

the.application.is.not.IRT-capable).during.a.“red.interval,”.they.are.temporarily.saved.in.an.IRT-capable.

switch.and.are.sent.only.aer.completion.of.the.“reserved.interval.”. e.frame.IDs.used.to.identify.the.dif-

ferent

.frames.is.specied.during.plant.conguration.in.the.engineering.tool.. e.receipt.of.the.cyclic.data.

is.timed.exactly.such.that.the.synchronous.application.can.be.started.directly.without.delays.

Orange interval:

.Only.RT_CLASS_2.frames.may.be.forwarded.through.switches.in.this.interval.. e.

forwarding.rules.dened.in.IEEE.802.1D.are.used.here.. e.“orange.interval”.starts.(if.present).imme-

diately

.at.the.start.of.a.“send.clock”.or.aer.the.“red.interval.”.RT_CLASS_2.frames.require.no.prior.

planning..As.a.result,.the.available.band.width.is.not.optimally.used..Receipt.of.the.cyclic.data.is.not.

timed.exactly..A.safety.reserve.must.therefore.be.included.

Green interval:

.For.forwarding.of.data.frames.in.switches,.the.rules.dened.in.IEEE.802.1D.apply..

Prioritization.can.occur.based.on.IEEE.802.1Q.(VLAN.tag)..If.IRT.frames.arrive.during.the.“green.

interval,”.they.are.destroyed.and.an.alarm.message.is.generated.. e.important.thing.is.that.no.jobs.are.

still.active.at.the.end.so.that.the.reserved.interval.can.start.unhindered..A.“green.interval”.does.not.have.

to.exist.within.a.phase.

Yellow interval:

. e.transition.from.the.“green.interval”.to.the.“red.interval”.is.preceded.by.a.“yellow.

interval”.in.which.an.IRT-suitable.switch.accepts.only.jobs.that.can.be.completely.transported.before.

the.start.of.the.next.“red.interval.”

For

.forwarding.data.frames.in.switches,.the.rules.dened.in.IEEE.802.1D.may.be.disabled.to.ensure.

the.start.of.the.next.reserved.phase..Prioritization.can.occur.based.on.IEEE.802.1Q.(VLAN.tag)..If.the.

forwarding.of.these.frames.before.the.start.of.the.next.reserved.interval.is.not.assured,.these.frames.are.

stored.temporarily.and.sent.in.the.next.“green.interval.”

40.3.1 Flexible Communication Based on rt_CLaSS_2 (Orange Interval)

For.communication.during.the.“orange.interval”.in.“switched.Ethernet.networks,”.the.conguration.of.end.

nodes.is.sucient..During.the.power-up.phase,.all.network.components.(switches).in.between.set.up.address.

tables.can.be.used.to.forward.the.received.frames.to.their.appropriate.destinations.. e.communication.is.

trained.in.a.quasi.manner.using.“source.and.destination.MAC.addresses.”. e.rules.dened.in.IEEE.802.1D.

are.used.here..In.the.“orange.interval,”.data.must.always.be.exchanged.in.conjunction.with.bus.synchroniza-

tion

.(synchronized.RT_CLASS_2)..Frames.are.transmitted.within.one.Send.clock.in.the.“orange.interval,”.in.

RT_CLASS_3

RED

(optional)

RT_CLASS_2

ORANGE

(optional)

Yellow

(optional)

Prio

...

Prio 6

RT_CLASS_2/1

Green (mandatory)

Max 60% of Tsend_cycle

31.25 μs ≤ Tsend_cycle ≤ 4 ms

Reserved interval Open interval

FIGURE 40.3 Bus.cycle.of.PROFINET.IO.with.IRT.communication.