BusWorks TM 900PB Series
ProfiBus/RS485 Network I/O Modules
Technical Reference
INTRODUCTION TO PROFIBUS DP
ACROMAG INCORPORATED Tel: (248) 624-1541 30765 South Wixom Road Fax: (248) 624-9234 P.O. BOX 437
Wixom, MI 48393-7037 U.S.A.
Copyright 2002, Acromag, Inc., Printed in the USA.
Data and specifications are subject to change without notice. 8500-698-A02M000
Introduction To ProfiBus DP
__________________________________________________________________
2INTRODUCTION TO PROFIBUS DP ABOUT PROFIBUS.……………………………………………
3PROFIBUS DP SLAVE STATE MACHINE..…………………
7Power ON/Reset State…………………………………..
7Parameterization State………………………………….
7I/O Configuration State………………………………….
7Data Exchange State…………………………………….
8Fail Safe Operation…………………..…………………..
8Watchdog……………………………..…………………..
9GSD FILES………………………………………………………
10REQUIRED SOFTWARE…..………………..…………………
13TYPES OF TRANSMISSION………………..…………………
14SRD Send and Request Data w/Acknowledge……..
14SDN Send Data w/No Acknowledge…………………..
14PROFIBUS DP DATA CHARACTER FORMAT…………….
14ProfiBus Data Error Checking………….……………..
15PROFIBUS TELEGRAM STRUCTURE……………………..
15Start Delimiter…………………………………………….
16Length Of Telegram……………………………………..
18Destination Address & Source Address……………..
18Function Code Or Frame Control……………………..
18Service Access Points…………………………………..
19Data Unit…………………………………………………..
19Frame Check Sequence…………………………………
19End Delimiter……………………………………………..
20DP COMMAND FUNCTIONS………………………………….
20Function Status…………………………………………..
20OPERATING STATES AND APPLICABLE FUNCTIONS....
21Initial Power ON/Reset…………………………………..
21Set_Slave_Add Telegram…………………………
22Parameterization……..…………………………………..
23Set_Prm Telegram………………………………….
24I/O Configuration……..…………………………………..
26Chk_Cfg Telegram………………………………….
26Get_Cfg Telegram………………………………….
27Diag_Data Telegram……………………………….
27Data Exchange State..…………………………………..
33Data_Exchange Telegram……..………………….
33Read_Inp Telegram……..………………………….
33Read_Outp Telegram…………..………………….
34Global_Control Services..……..………………….
34Use Of Freeze..……..……..………………….
35Use Of Sync/Unsync.……..………………….
35BUS TIMING (36)
This information is provided as a service to our customers and to others
interested in learning more about Profibus. Acromag assumes no
responsibility for any errors that may occur in this document, and makes no
commitment to update or keep this information current.
Be sure to visit Acromag on the web at https://www.doczj.com/doc/7213320556.html,.
Windows? is a registered trademark of Microsoft Corporation.
Modbus? is a registered trademark of Modicon, Incorporated.
TABLE OF
CONTENTS
Introduction To ProfiBus DP
___________________________________________________________________3 The following information describes the operation of ProfiBus DP as it
relates to Acromag Series 900PB DP slave I/O modules. For more detailed
information on ProfiBus, you may refer to the ProfiBus Trade Organization at
the PTO website https://www.doczj.com/doc/7213320556.html,.
Acromag manufactures a line of I/O modules that support Profibus DP
over RS485. Feel free to visit our website at https://www.doczj.com/doc/7213320556.html, to obtain
the latest information about these and other Acromag products.
Acromag Series 900PB modules utilize the popular ProfiBus DP
ABOUT PROFIBUS FieldBus communication format. ProfiBus was created in 1989 by the
German government in cooperation with several manufacturers of
automation equipment. It is a messaging format specifically designed for
high-speed serial I/O in factory and building automation applications. It is an
open standard and is recognized as the fastest FieldBus in operation today.
It is based on RS485 and the European EN50170 Electrical Specification.
The DP suffix refers to “Decentralized Periphery”, which is used to describe
distributed I/O devices connected via a fast serial data link with a central
controller. To contrast, a programmable logic controller (PLC) normally has
its input/output channels arranged centrally. By introducing a network bus
between the main controller (master) and its I/O channels (slaves), we have
decentralized the I/O.
ProfiBus is based on universal international standards and oriented to
the OSI (Open System Interconnection) reference model per international
standard ISO 7498. In this model, every layer handles precisely defined
tasks. Layer 1 of this model is the physical layer and defines the physical
transmission characteristics. Layer 2 is the data link layer and defines the
bus access protocol. Layer 7 is the application layer and defines the
application functions. ProfiBus DP uses only layers 1 & 2 of this model, plus
the user interface. Layers 3 to 7 are not used.
A ProfiBus system uses a bus master to poll slave devices distributed in
multi-drop fashion on an RS485 serial bus. A ProfiBus slave is any
peripheral device (I/O transducer, valve, network drive, or other measuring
device) which processes information and sends its output to the master.
The slave forms a “passive station” on the network since it does not have
bus access rights, and can only acknowledge received messages, or send
response messages to the master upon request. It is important to note that
all ProfiBus slaves have the same priority, and all network communication
originates from the master. Acromag I/O modules form intelligent slave
devices.
Acromag modules implement the ProfiBus protocol via an industry-
standard SPC3 ASIC from Siemens. This ASIC acts like a RAM or UART
chip to the internal microcontroller and completely handles the requirements
of the protocol standard. The ASIC will transfer network data to and from
the microcontroller and automatically provide the response to the bus
according to the ProfiBus specification.
4
Introduction To ProfiBus DP __________________________________________________________________
A ProfiBus master forms an “active station” on the network. ProfiBus
DP defines two classes of masters. A class 1 master handles the normal
communication or exchange of data with the slaves assigned to it. A class 2
master is a special device primarily used for commissioning slaves and for
diagnostic purposes. Some masters may support both class 1 and class 2
functionality. Master-to-master communication is normally not permitted in
Profibus, except in order to grant bus access rights to another master via the
exchange of a token. However, master-to-master communication between
two mono-master systems can be facilitated using a DP-DP gateway. Note
that the exchange of bus access rights via this “token ring” only applies
between masters on the bus.
A class 1 master device is normally a central programmable controller
(PLC), or a PC running special software. The class 1 master sets the baud
rate and the slave’s auto-detect this rate. The class 1 master handles the
data exchange with the slaves assigned to it, and acts as the main controller
for the exchange of I/O information with its distributed slaves, cyclically
retrieving user I/O data according to a defined message cycle. A master can
communicate actively with its assigned slaves, but only passively (upon
request) with another class 2 master device.
The class 2 master is usually a configuration device, perhaps a laptop
or programming console, and is provided for commissioning, maintenance,
or diagnostic purposes. It acts like a “supervisory” master in that it can
actively communicate with class 1 masters and their slaves, in addition to its
own slaves, but usually only for the purpose of configuration, problem
diagnosis, and data/parameter exchange. That is, class 2 masters may only
briefly take over control of a slave. All exchanges between a class 2 master
and class 1 master originate with the class 2 master.
ProfiBus DP normally operates using a cyclic transfer of data between
master(s) and slave(s) on an RS485 network. That is, an assigned master
periodically requests (polls) each node (slave) on the network. All data
communication exchanges between a master and slave originate from the
master device. Each slave device is assigned to one master and only that
master may write output data to that slave. Other masters may read
information from any slave, but can only write output data to their own
assigned slaves.
Masters can address individual slaves, a defined group of slaves (multi-
cast), or can broadcast a telegram to all connected slaves. Slaves will return
a response to all telegrams addressed to them individually, but do not
respond to broadcast or multi-cast telegrams from a master device.
ProfiBus sends Broadcast and Multi-Cast messages as global control
telegrams using address 127 and an optional group number for a targeted
group of slaves.
Because ProfiBus uses a cyclic (periodic) polling mechanism between
masters and slaves, it is also deterministic. That is, the behavior of a
ProfiBus system can be reliably predicted over time. In fact, ProfiBus was
designed to guarantee a deterministic response. To contrast, CAN and
Ethernet are event-driven bus systems and consequently form non-
deterministic systems.
Introduction To ProfiBus DP
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The length (and timing) of the I/O data to be transferred from a single
slave to a master is predefined in the slave’s device data base or GSD file.
The GSD files of each device connected via the network (slaves and class 1
masters only) are compiled into a master parameter record which contains
parameterization and configuration data, an address allocation list, and the
bus parameters for all connected stations. A master uses this information to
set up communication with each slave during startup.
After a master receives its master parameter record, it is ready to begin
exchanging data with its slaves. During startup, after a system reset, or
upon return to power, a master will attempt to re-establish contact with all the
slaves assigned to it before assuming the cyclic exchange of I/O data. Each
slave must already have a unique valid address from 0-125 in order to
communicate with the master. Any slave that has a default address of 126
will await the Set_Slave_Address command from a class 2 master before it
can be parameterized. In attempting to establish communication, the master
starts with the lowest address slave and ends with the highest address
slave. A master will send parameterization and configuration telegrams to all
of its assigned slaves (a slave may only be write-accessed by its assigned
master, the master that parameterized and configured it during startup). The
parameterization and configuration telegrams ensure that the functionality
and configuration of a slave is known to the master. If an additional slave is
added to the network bus and is not already accounted for in the master
record, a new master record must be generated and a new configuration
performed so that the master is informed of the status of the new device.
ProfiBus DP most often uses a single class 1 master device (mono-
master), cyclically polling many distributed slaves. However, ProfiBus also
allows for acyclic communication between class 2 masters and slaves,
making more than one active station or master possible. A class 1 master
will automatically detect the presence of a new active station connected to
the network bus (a class 2 master). When the class 1 master completes its
polling cycle, it will pass a “token” to the class 2 master granting it temporary
access to the bus. Deterministic behavior is maintained because the class 2
master can only use the time allotted to it via the gap time specified.
Although, mono-master operation is generally recommended, it is not
mandatory. That is, a ProfiBus system may have more than one class 1
master, but master to master communication is not permitted, except for the
granting of bus access rights via token exchange.
To illustrate the idea of communication between masters in a ProfiBus
DP system, a class 1 master cyclically exchanges data with all of the slaves
assigned to it, one at a time, according to its list of assigned slaves taken
from the master record. At the end of this data cycle, additional time (gap
time) is allotted to provide for acyclic communication between a class 2
master and the same slaves. During this time, the class 1 master will pass a
token to the class 2 master granting it bus access rights. The class 2
master which currently holds the token has the opportunity to exchange data
with all the slaves within a specific period of time called the token half-time or
token hold-time (T H). The class 2 master may then proceed to read data or
diagnostic information from any of the slaves, and then at the completion of
its cycle, it will pass the token back to the class 1 master.
6
Introduction To ProfiBus DP __________________________________________________________________
Since there usually is not enough time during the gap to complete a full data
exchange, this process of data retrieval by the class 2 master may continue
over several cycles. At the end of record transfer, the class 2 master will
clear the connection. Note however, that the class 2 master may only
establish communication with the slaves during the gap time.
As stated earlier, it is possible for a class 2 master to temporarily take
over control of a DP slave. During this time, the DP slave will stop its normal
data exchange with its class 1 master. The class 1 master recognizes this
and will proceed to cyclically request diagnostics from the slave, checking
the Master Address field for as long as another valid address is present.
After the class 2 master finishes its communication with the slave, it sets the
Master Address field of the slave to invalid (255). This causes the class 1
master to attempt to regain control of the slave and it will reparameterize and
reconfigure the slave before resuming data exchange with it.
ProfiBus DP –
Key Concepts
?Open standard based on EN 50170.
?Fastest Fieldbus standard to date with data rates up to 12MB.
?Plug & play operation.
?Up to 244 bytes of input/output data per message.
?Up to 126 stations may connect to the bus.
?Up to 32 stations per bus segment.
Class 1 Master –
?Central controller that exchanges I/O data with connected slaves.
?Determines the baud rate (slaves auto-detect this rate).
?Manages the token transfer between masters. Detects another
master during the gap time.
Class 2 Master –
?Diagnostic, configuration, or startup tool.
?Can only control one slave at a time.
?Does not have write-access to the slave.
?Does not have a GSD file.
Slave -
? A passive station which can only respond per a master request and
acknowledge messages. A slave has no bus control rights.
?The GSD file defines the slave for the master.
Introduction To ProfiBus DP
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7The following state machine helps illustrates how ProfiBus DP operates
with respect to the slaves.
Note the four main states:Power ON/Reset,Parameterization, I/O Configuration, and Data Exchange.The master uses the following general telegram sequence during startup:1. Request Diagnostics.2. Change Station Address (optional service, Class 2Master only).3. Parameterize the Slaves.4. Configure the Slaves.5. Request Diagnostics
again before data
exchange to ensure that
system startup was OK.
6. Data exchange.
7. Global Control (optional).Power ON/Reset State
The power on/reset state is the initial state following power up for the
DP slave. In this state, the slave may receive a telegram from a class 2
master to change its station address. A slave will be held in this state if it
does not have a valid address from 0-125. After completion of its power-on
initialization routine and if the slave has a valid station address, the slave will
proceed to the Wait for Parameterization state.
Parameterization State
In this state, the DP slave awaits the parameterization telegram from
the master which identifies the slave’s master and the mode the slave is to
operate in. A slave in this state will reject all other telegrams except a
request telegram for diagnostics or configuration. After its parameters have
been set, the slave will proceed to the I/O Configuration State.
I/O Configuration State
In this state, the slave awaits a configuration telegram that specifies the
number of input and output bytes that are to be exchanged in each data
telegram cycle with the slave. The configuration telegram also causes the
slave to check the configuration which was sent against the stored
configuration. A slave in this state will accept a request telegram for
diagnostics or configuration, or a set parameters telegram.
PROFIBUS DP SLAVE STATE MACHINE
8
Introduction To ProfiBus DP __________________________________________________________________
Data Exchange State
After parameterization and configuration have been accomplished, the
slave cyclically exchanges I/O data with the master. This is a cyclic transfer
of I/O data and possible diagnostic information.
Fail Safe Operation
A ProfiBus master runs in two modes: Operate and Clear. With
respect to the master of a ProfiBus DP system, the term fail-safe simply
refers to whether the class 1 master sends 0 length data, or data set to 0,
when it is in Clear Mode. With respect to a DP slave device, the term fail-
safe refers to whether the slave will process output telegrams with zero
length data, or not. Whether the combined master/slave system is
considered fail-safe depends on the actions taken by the slaves if the master
fails, or if the master switches to Clear Mode. Ideally, the failure of a master
should not cause errors in any of its slaves and the slave outputs should go
to a predictable (defined) state. Using a fail-safe mode, the slave outputs
can automatically switch to a fail-safe state in the event of master failure, or
when the master switches to Clear Mode.
A slave may assume a fail-safe state if its watchdog time expires
without having received a message from its assigned master. Normally this
timer is reset every time the master talks to the slave. If this time expires,
this means the master has not communicated with the slave recently, and
the slave is not being controlled. The slave will then leave the data
exchange mode and its outputs will go to a pre-defined state (either their
reset state, or another user-defined state). This state is usually set via user-
defined parameters of the parameterization telegram and its GSD file, or
sometimes via hardware switches on the slave. Some slaves may provide
parameters or switches that also allow the slave outputs to retain their last
state, but this is not considered fail-safe.
A slave may also assume a fail-safe state if its master switches from
Operate Mode to Clear Mode. With normal operation in Data_Exchange
mode, a class 1 master is in Operate Mode and cyclically exchanges I/O
data with its assigned slaves. The class 1 master may use a global control
telegram to inform the slaves that it is switching from Operate Mode to Clear
Mode. A master may elect to switch to Clear Mode while it is bringing slaves
online and not all slaves have been parameterized and configured yet. It
may also switch to Clear Mode as a result of a run/stop switch on the
master. In the Clear State, the master may attempt to parameterize and
configure the remaining slaves assigned to it in an effort to reinitiate data
exchange, while it continues data exchange with the other slaves (they will
be receiving output data of 0, or output data of zero length). Operate mode
does not resume until all slaves are online and exchanging data, or until the
master is told to resume operation via a run/stop switch or under program
control. Further, some masters may go to Clear Mode if a slave is disabled,
rather than continue to control a partial system (this response may be
specified as a parameter in the master’s GSD file and parameterization
telegram, via a mechanical switch, or as part of its master program).
Introduction To ProfiBus DP
___________________________________________________________________9
When a master switches to Clear Mode, it sends a global control
telegram to all slaves with the first data byte (octet 1) = 2 and the second
data byte (octet 2) = 0. In the next data cycle, the master sends data
telegrams to all stations with either the output data equal to 0, or the output
data length equal to 0 (i.e. only the telegram header and no data). If the
slave GSD file contains “Fail_Safe = 0”, the master sends output telegrams
with the data set to 0 in Clear Mode. However, if the slave GSD file contains
“Fail_Safe = 1” (supports Fail-Safe Mode), the master will send output
telegrams with a data length of 0 in Clear Mode. . Slaves that do not support
fail-safe mode do not process data telegrams with no data. Some older
masters do not make this distinction of fail-safe mode and will send data
telegrams with the output data set to 0 in Clear Mode. This will force all
slave outputs to go to 0 in Clear Mode and this may not be desirable for
some critical control applications.
By the master sending output telegrams with no data in Clear Mode, a
fail-safe slave has the option of either setting all outputs to 0, retaining the
last output state (though this response is not fail-safe), or going to a pre-
defined default “fail-safe” state. This state may be defined in the GSD file
and included in the user-parameters portion of the parameterization
telegram, or it may be set via switches at the slave. The slave will stay in
this state until it receives a global control broadcast telegram from the
master telling it the master is returning to Operate Mode and it receives an
output telegram with the correct output data length, whereupon it updates its
outputs normally as part of data exchange mode.
To summarize, fail-safe mode in ProfiBus DP simply refers to whether
the master sends output data messages of zero length in Clear Mode or not,
and whether a slave is able to process output messages of zero length. The
actions taken by the slave in response to these messages is optional and
specific to the slave implementation. Note that a “fail-safe” slave may not
actually act in a fail-safe manner (for example, it may retain the last state
prior to Clear Mode). In any case, for PTO compliance, a fail-safe slave
must at least give the option of clearing the outputs if the master fails or
switches to Clear Mode.
Watchdog
A slave may assume a defined state if its watchdog time expires without
having received a message from its assigned master. Normally this timer is
reset by the slave every time the master talks to the slave. If this time
expires, this means the master has not communicated with the slave
recently, and the slave is not being controlled. A communication error is
detected by the slave and reported with a diagnostic telegram (see function
codes). The slave will then leave the data exchange mode and its outputs
will go to a predefined state (either the reset/clear state, or a user-defined
state) and await reparameterization and reconfiguration by the master. The
timeout state is clear by default, or it may be set via user-defined parameters
of the parameterization telegram and GSD file, or sometimes via hardware
switches on the slave. Some slaves may provide parameters or switches
that also allow the slave outputs to retain their last state, but this is not
considered fail-safe.
10
Introduction To ProfiBus DP __________________________________________________________________
During parameterization, a master sets up the communication and
monitoring times for the slave including the watchdog time (T WD set by
Watchdog Factors in DU bytes 2 & 3 of the Set_Prm Telegram). The slave
ASIC implements a watchdog function where the slave will monitor the bus
communications with the master over time, and in the event of master failure
(timeout), the slave outputs go to a defined state. If the watchdog timer is
not retriggered by the slave station via bus communication with the master
within the time specified, then the slave will set its outputs to a defined state
and return to the Wait_Prm state (Wait For Parameterization). In setting
watchdog time T WD, you need to consider the bus cycle time, plus a safety
factor for repeated telegrams (usually 25% minimum).
Before we examine slave operation in detail, we need to get a little
background information on a device’s GSD file and how the software is used
to build a ProfiBus system.
The GSD file is an electronic device data sheet or device data base file GSD FILES
that identifies the ProfiBus device. All ProfiBus devices (class 1 masters and
slaves) have their own GSD files. The GSD file is the fundamental building
block for the master parameter record. Use of the GSD file by a ProfiBus
configuration tool permits plug & play interoperability among different
devices from different manufacturers. This file does not reside within the
device itself, but usually on a separate disk/drive. It is an ASCII text file that
contains device-specific data, such as, vendor identification information,
supported baud rates, supported message length, number of input/output
data, meaning of diagnostic messages, timing information, plus options and
features supported, data formats, and available I/O signals. For modular
ProfiBus systems, a GSD file may contain several configurations (one for
each I/O module), one of which will be found valid during startup.
A GSD file is named by combining a vendor name identifier with the
device’s ident_ number. For example, “ACRO06F3.GSD” is used for the
Acromag 981PB-1012 device. The suffix “.GSD” denotes a language
independent GSD file. A “.GSE” file would specify an English file, “.GSF” for
French, “.GSS” for Spanish, “.GSI” for Italian, and “.GSG” for German.
The GSD file begins with the specifier “#Profibus_DP”. In the body of
the file, the parameters are specified as parameters of a keyword (as in
“keyword = parameter”, see below). Comment lines begin with a semicolon.
Case is not significant and the sequence of parameters is not important.
Lines are limited to 80 characters, but may be continued by placing a
backslash character “\” at the end of the line to be continued. A GSD file is
divided into sections as follows:
Introduction To ProfiBus DP
___________________________________________________________________11GSD General Specifications
Keyword Keyword Vendor_name 187.5_supp Model_Name 500_supp Revision 1.5M_supp Ident_Number MaxTsdr_9.6Protocol_Ident MaxTsdr_19.2Station_type MaxTsdr_93.75FMS_Support MaxTsdr_187.5Hardware_Release MaxTsdr_500Software_Release MaxTsdr_1.5M 9.6_supp
Redundancy 19.2_supp Repeater_Ctrl_Sig This section contains
information on vendor and
device names, hardware and
software revisions,
ident_number, supported baud
rates, reaction time intervals at
supported baud rates for
monitoring times, and optional
signal support at the bus
connector.93.75_supp 24V_Pins GSD Slave Specifications Keyword
Keyword Freeze_Mode_supp
Max_Input_Len Sync_Mode_supp
Max_Output_Len Auto_Baud_supp
Max_Data_Len Set_Slave_Add_supp
Unit_Diag_Bit User_Prm_Data_Len
Diag_Text User_Prm_Data
Unit_Diag_Area Min_Slave_Intervall
Module Modular_Station
Channel_Diag This section contains all slave-related specifications,such as the number and type of I/O channels, specification of diagnostic text, auto-baud support, alternate mode support and information on available modules with modular devices.
Max_Module Master Specifications (Master Devices Only): This section contains all
master-related parameters, such as: the maximum number of slaves that
can be connected, or upload/download options. This section is not present
for slave devices and not covered here.
The GSD files of all connected devices are compiled together to form
the master parameter record. The master parameter record contains the
parameterization and configuration data taken from the all the GSD files, and
includes an address allocation list, plus the bus parameters for all the
connected slaves. During startup, a master will use this information to set
up communication with each of its assigned slaves prior to exchanging
actual I/O data with them.
The ProfiBus Trade Organization offers an easy to use, menu-driven
editor which can be used to prepare GSD files. This GSD-Editor also
contains a GSD-Checker which guarantees the conformance of the GSD file
to the ProfiBus standard. The format of GSD files is precisely specified in
the EN50170 standard and described in ProfiBus Guideline 2.041.
The ProfiBus Trade Organization also maintains a library of GSD files
for all certified slave devices. You can access these files via the internet at
https://www.doczj.com/doc/7213320556.html, .
GSD FILES
12
Introduction To ProfiBus DP __________________________________________________________________
To give you an idea of what a GSD file might look like, consider the
following partial GSD file taken from Acromag Model 983PB-2012.
#Profibus_DP
GSD_Revision= 1; Version of the GSD file
Vendor_Name= “Acromag, Inc.”; Vendor name
Model_Name= “983PB-2012”; Product name
Revision= “A”
Ident_Number= 0x06F1 ; Ident Number
Protocol_Ident= 0; ProfiBus DP Only (1-DP/FMS)
Station_Type= 0; Type of device (Slave)
Hardware_Release= “A”; Hardware version of the device
Software_Release= “A”; Software version of the device
;
9.6_supp= 1; 9600bps Supported
19.2_supp= 1
93.75_supp= 1
187.5_supp= 1
500_supp= 1
1.5M_supp= 1
3M_supp= 1
6M_supp= 1
12M_supp= 1
MaxTsdr_9.6= 60; Maximum response time
MaxTsdr_19.2= 60; at different baud rates.
MaxTsdr_93.75= 60
MaxTsdr_187.5= 60
MaxTsdr_500= 100
MaxTsdr_1.5M= 150
MaxTsdr_3M= 250
MaxTsdr_6M= 450
MaxTsdr_12M= 800
;
Redundancy= 0; Redundancy Not Supported
Repeater_Ctrl_Sig= 2; Includes RTS Support w/TTL
Implementation_Type= “SPC3”; Uses Siemens SPC3 ASIC
24V_Pins= 0; Does Not Include 24V
Fail_Safe= 1; Supports Fail-Safe Mode
Freeze_Mode_supp= 1; Supports FREEZE
Sync_Mode_supp= 1; Supports SYNC
Auto_Baud_supp= 1; Includes Auto Baud Detection
Set_Slave_Add_supp= 1; Addr can be set via ProfiBus
User_Prm_Data_Len= 3
User_Prm_Data= 0x00,0x00,0x00; Module Specific Parameters
; 00H = Set outputs to 0
; 01H = Maintain Last Output Values
; 02H = Set output to user-defined values in bytes 1 and 2
; Byte 1 is the lower byte of user-defined output data which is outputs 0 to 7
; Byte 2 is the upper byte of user-defined output data which is outputs 8 to 11
;
Introduction To ProfiBus DP
___________________________________________________________________13
Slave_Family= 3
Min_Slave_Interval= 1; Min_Slave_Interval is 100us
Modular_Station= 0; 0-compact, 1-modular
Max_Diag_Data_Len= 6; No User Diagnostics are Sent
; I/O Byte
Module= “12 CH DIG I/O:xxxx1198 76543210” 0x11,0x21
EndModule
;
Leading PLC manufacturers offer configuration software for their
REQUIRED SOFTWARE products that make it easy to generate the master parameter record for their
devices. This software is generally master-specific and depends on the
design of the master device. In order to setup a ProfiBus system, you will
need a software configuration tool, such as Allen Bradley’s Plug and Play
software, or the Siemens COM ProfiBus package. This software configures
the active stations and tells them what devices are present on the bus and
how much data it needs to exchange with them.
Recall that the master parameter record contains all the required data
for the bus system, including an address allocation list and the bus
parameters of the connected slaves. The address allocation list assigns
each remote I/O byte a unique address in the I/O space of the master’s I/O
space.
As an alternative method to PLC specific software, Siemens offers an
easy to use configuration tool called COM PROFIBUS that can be run on
any PC (offline version). An online version of COM PROFIBUS requires an
interface card.
The configuration software utilizes the GSD files (device master data) of
the connected slaves to create the master parameter record. This record is
typically transferred or downloaded to the class 1 master from floppy disk,
dual port RAM, or Flash EPROM. Typically, if you need to add another slave
to an existing system, you simply upload the current master parameter
record, add the new parameterization data for the slave (imported from the
GSD file), then download the new master record to the master again. Since
an active bus station automatically detects a new active bus station, you can
then perform a reset, and the bus system will reconfigure itself.
In addition to the slave-specific data which the configuration tool
gathers from the GSD file, you may also have to provide the following bus
and protocol-related data via the configuration tool:
?The Protocol Used (DP, FMS, or mixed network).
?The transmission baud rate (the tool checks to determine whether
all stations or slaves actually support this speed).
?The GAP factor (number of bus passes after which an additional
active station is searched for). A master automatically detects the
connection of other masters via a periodic search driven by this
factor.
?The Highest Station Address (HSA).
?The Watchdog Time.
?Within a PLC, the CPU type and type of addressing used.
Introduction To ProfiBus DP
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14Most configuration tools also allow you to permanently store user
parameters and configuration bytes which the master will automatically send
to the slave during system startup.
ProfiBus DP uses two types of transmission services in sending
message telegrams that are defined in Layer 2 (The Data Link Layer) of the
ISO/OSI model and summarized below:SRD (Send and Request Data with acknowledge)
With SRD, data is sent and received in one telegram cycle. That is, the
master sends output data to the slave and receives input data from the slave
in its response (if applicable) within a specified period of time. The important
thing to remember about this service, is that a master may send output data
to a slave and request input data from the slave in its response, all in a
single telegram cycle. This is the transmission service most often used in
ProfiBus DP that makes the data exchange very efficient for mixed I/O
devices.SDN (Send Data with No acknowledge)
This service is used when a message must be sent simultaneously to a
group of slaves (multi-cast), or all slaves (broadcast). Slaves do not respond
or acknowledge broadcast or multi-cast messages.
A third type of transmission service used in ProfiBus FMS is SDA (Send
Data with Acknowledge), with data sent to a master or slave and a short
acknowledgement sent in response. This is not used in ProfiBus DP and is
not covered here.All ProfiBus characters are comprised of 11 bits (1 start bit + 8 data bits + 1 even parity bit + 1 stop bit). ProfiBus DP exchanges data in NRZ code (Non Return to Zero). That is, the signal form of binary “0” or “1” does not
change during the duration of the bit. If nothing is being transmitted, the idle
state potential on the line is “1”. A start bit causes the line to go to “0”.ProfiBus NRZ-Coded Character Frame (Even Parity)
Start D0D1D2D3D4D5D6D7
Parity Stop “0”01234567
even “1”←LSB ←←←←←←MSB ←←
This character frame applies to all data/character bytes, including the
telegram header bytes. When messages are transmitted on ProfiBus serial
networks, each character or data byte is sent in the order of least significant
bit (lsb) to most significant bit (msb), as shown above. For word transfer
(more than 1 byte), the high byte is transmitted first, followed by the low byte
(Big-Endian/Motorola format).
TYPES OF TRANSMISSION
PROFIBUS DP
DATA CHARACTER
FORMAT
Introduction To ProfiBus DP
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15ProfiBus networks employ the even parity method of data error
checking which controls how the parity bit of a data frame is set.
With even parity checking, the number of 1 bits in the data portion of
each character frame is counted. Each character contains 8 bits. The parity
bit will then be set to a 0 or 1, as required in order to result in an even total
number of 1 bits. For example, if a character frame contains the following
eight data bits: 1100 0011, then since the total number of 1 bits is 4 (already
an even number), the frame’s parity bit will be set to 0 for even parity.
When a message is transmitted, the parity bit is calculated and applied
to the frame of each character transmitted. The receiving device counts the
quantity of 1 bits in the data portion of the frame and sets an error flag if the
count differs from that sent. As such, parity checking can only detect an
error if an odd number of bits are picked up, or dropped off, from a character
frame during transmission. For example, with even parity, if two 1 bits are
dropped from a character, the result is still an even count of 1 bits and no
parity error will be detected.
A ProfiBus telegram may contain up to 256 bytes--up to 244 bytes of
data per node per message, plus 11 bytes of overhead. This overhead is
referred to as the Telegram Header . All telegram headers are 11 bytes,
except for Data_Exchange telegrams which have 9 bytes of header
information (the DSAP and SSAP bytes are dropped). Note that 12 bytes is
a lot of overhead for a single message and this makes ProfiBus less efficient
for small amounts of data. However, since up to 244 bytes of data may
occur per message, and since the output data is sent and the input data
received in a single telegram cycle, this makes ProfiBus more efficient when
large amounts of data must be transferred. Note that an idle state of at least
33Tbits (sync-time in bit time) must be present before every request
telegram to be sent, and all data is transferred without gaps between
individual characters. All data exchanges between a Master and Slave are
handled in the telegram header using Service Access Points (SAP’s).
ProfiBus DP uses SAP’s 54 to 62, plus the default SAP (Data_Exchange).Telegram Header Data and Frame
SD LE LEr SD DA SA FC
DSAP SSAP DU FCS ED 1b 1b 1b 1b 1b 1b 1b 1b 1b var 1b 1b
ProfiBus Data Error Checking PROFIBUS TELEGRAM (MESSAGE)STRUCTURE
Introduction To ProfiBus DP
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16ProfiBus DP Telegram Header Abbreviations and Frame Bytes
SD 1 byte Start Delimiter (used to distinguish telegram
format).
LE 1 byte Net Data Length (DU) + DA + SA + FC + DSAP +
SSAP.
LEr 1 byte Length repeated.
DA 1 byte Destination Address– Where this message goes to.
SA 1 byte Source Address – Where this message came from.
The address of the sending station.
FC 1 byte Function Code (FC=Type/Priority of this message).
Used to identify the type of telegram, such as
request, acknowledgement, or response telegrams
(FC=13 signals diagnostic data). See below.
DSAP 1 byte Destination Service Access Point (COM port of
receiver). The destination station uses this to
determine which service is to be executed.
SSAP 1 byte Source Service Access Point (COM port of sender).
DU 1 to 32b
(or 1-244b)
Data Units/ Net Data from 1 to 244 bytes.
FCS 1 byte Frame Checking Sequence (ASIC addition of the
bytes within the specified length).
ED 1 byte End Delimiter (always 16H).
The following picture depicts the telegram sequence between a class 1
master and DP slave. The paragraphs that follow describe each telegram
frame byte in greater detail.
The Start Delimiter identifies the beginning of a telegram and its general
format. ProfiBus DP uses four types of Start Delimiters (SD) for request and
response telegrams, plus a fifth response for a short acknowledgement as
shown below. Note that the short acknowledge response does not use a
start delimiter. Also, a telegram response does not have to use the same
Start Delimiter as the request telegram.
Start Delimiter (SD)
Introduction To ProfiBus DP
___________________________________________________________________17
Telegram
Format Value Data Field Length
SD110H0 bytes (No Data Field)
SD268H 1 to 32 bytes (or up to 244)
SD3A2H8 bytes fixed.
SD4DCH0 bytes (No Data Field)
SC E5H0 bytes (No Data Field), Short Acknowledge.
Start Delimiter SD1 (SD=10H) = Request_FDL_Status
Telegram with fixed information section and no data field…
SD1DA SA FC FCS ED
10H xx Xx x x16H
An active station sends this telegram to look for new active stations on
the bus after the GAP time has expired.
Start Delimiter SD2 (SD=68H) = Telegram w/ variable DU.
Telegram with variable information section and data field length…
SD2LE LEr SD DA SA FC DSAP SSAP DU FCS ED
68H X x68H xx xx x3CH3EH x..x X16H
←-----------VAR LENGTH-------------→
Data telegram with variable data length. Used in SRD service (Send
and Request Data with acknowledge) which allows output data to be sent
and input data to be received in one telegram cycle.
Start Delimiter SD3 (SD=A2H) = Telegram w/ fixed DU.
Telegram with fixed information section and data field length…
SD3DA SA FC DU FCS ED
A2H xx xx x x..x x16H
This delimiter is used for data telegrams with fixed data length (the DU
data is always 8 bytes long).
Start Delimiter SD4 (SD=DCH) = Token Telegram
Master-to-master token telegram…
SD4DA SA ED
DCH xx xx16H
This delimiter is used between 2 active bus stations to grant bus access
rights.
No Start Delimiter
No Start Delimiter - Short Acknowledgement Telegram…
SC E5H The short acknowledgement frame SC is a 1 byte message that can be used to positively acknowledge an SDA request (ProfiBus FMS only), or negatively acknowledge an SRD request.
Introduction To ProfiBus DP
__________________________________________________________________
18This byte specifies the length of a telegram with variable data length
(i.e. SD2 Telegrams) from the DA byte to the end DU byte (range is DU+5b
to 249). Note that the length of the DU is generally limited to 32 bytes, but
the standard allows for lengths up to 244 bytes. LE is repeated in the LEr
field for redundant data protection.
The master device addresses a specific slave device by placing the 8-
bit slave address in the DA address field of the telegram (Destination
Address). It includes its own address in the SA address field (Source
Address). Valid addresses are from 0-127 (00H..7FH). Address 126 is
reserved for commissioning purposes and may not be used to exchange
user data. Address 127 is reserved as the broadcast address, which all
slave devices on a network recognize. When the slave responds, it will
place its own address in the source address field of its response to let the
master know which slave is responding, and it will place its assigned
master’s address in the destination address field of its respone. Recall that
a slave does not issue a response to broadcast messages (address 127).
Note that the inclusion of a DSAP or SSAP entry in a request or
response telegram is identified by setting the highest bit in the address byte
of the DA (Destination Address) or SA (Source Address), respectively. This
may look like an address greater than 127, but only the lower 7 bits of the
DA and SA contain the actual address.The Function Code (FC) or Frame Control field specifies the type of telegram (request, response, acknowledgement), type of station (passive or
active/slave or master), priority, and telegram acknowledgement (successful
or unsuccessful) as follows:ProfiBus DP Function Codes for Request Telegrams
FC Code Function (The MSB in FC = 1)
4SDN low (Send Data with No acknowledge)
6SDN high (Send Data with No acknowledge)
7Reserved/Request Diagnostic Data
9Request FDL Status With Reply
12SRD low (Send and Request Data with acknowledge)
13SRD high (Send and Request Data with acknowledge)
14Request ID With Reply
15Request LSAP Status With Reply ProfiBus DP Function Codes for Acknowledgement Telegrams
FC Code Function (The MSB in FC = 0)
0ACK Positive
1ACK Negative (FDL/FMA1/2 user error UE, interface error)
2ACK Negative (No resource/memory space for Send Data (RR).
3ACK Negative (No service activated (RS), SAP not activated).
8Response FDL/FMA ? Data low and Send Data OK)
9ACK Negative (No response FDL/FMA1/2 Data & Send Data OK).
10Response FDL Data High and Send Data OK.
12Response FDL Data Low, No resource for Send Data.
13Response FDL Data High Resource For Send Data.
Length of Telegram (LE & LEr)Destination Address &Source Address (DA & SA, 00H..7FH)
Function Code or
Frame Control (FC)
Introduction To ProfiBus DP
___________________________________________________________________
19Data exchanges are handled in the telegram header using Service
Access Points (SAP’s). The SAP tells what data is to be transmitted or which function is to be performed. Only telegrams that include data fields use DSAP & SSAP bytes (i.e. SD2 & SD3 telegrams). Recall that SRD
transmission combines an output message with an input response in a
single telegram cycle. The telegram header contains an SSAP (Source
Service Access Point) and/or DSAP (Destination Service Access Point) that
indicates the service(s) to be executed. One exception is the cyclical
Data_Exchange telegram which is performed with the default SAP (SSAP or
DSAP is not provided in its header). Additionally, some telegrams may only
provide a DSAP or SSAP, but not both.
The inclusion of a DSAP or SSAP entry in a request or response
telegram is identified by setting the highest bit in the address byte of the DA
(Destination Address) or SA (Source Address), respectively. Based on the
detected SAP’s, each station is able to recognize which data has been
requested and which response data is to be supplied. ProfiBus DP uses
SAP’s 54 to 62 listed below, plus the default SAP.SAP
SERVICE Default SAP=0
Cyclical Data Exchange (Write_Read_Data)SAP54
Master-to-Master SAP (M-M Communication)SAP55
Change Station Address (Set_Slave_Add)SAP56
Read Inputs (Rd_Inp)SAP57
Read Outputs (Rd_Outp)SAP58
Control Commands to a DP Slave (Global_Control)SAP59
Read Configuration Data (Get_Cfg)SAP60
Read Diagnostic Data (Slave_Diagnosis)SAP61
Send Parameterization Data (Set_Prm)SAP62Check Configuration Data (Chk_Cfg)SAP55 is optional and may be disabled if the slave does not provide
non-volatile storage memory for the station address. Note that SAP’s 56, 57,
and 58 are not enabled until the DP slave assumes the Data_Exchange
state. SAP’s 59, 60, 61, and 62 are always enabled.
Note that the DSAP & SSAP entries in a request telegram are also
included in the response telegram, where DA + SA + DSAP + SSAP in the
response message corresponds to SA + DA + SSAP + DSAP in the request
telegram (content position flips).
This field contains the data for the station at DA (request data), or the
data for the station at SA (response data). DU is generally limited to 32
bytes, but the standard allows for lengths up to 244 bytes (assuming 11
bytes of header information for 255 bytes total).
This field contains the Frame Check Sequence or telegram checksum
(00H..FFH). It is simply the sum of the ASCII bytes of information from DA
to DU modulus 256. Checksum = (DA + SA + FC + DU) mod 256. This is
simply the bytes added together and divided by FFH (255). This is an
integrated function that is normally performed by the ProfiBus ASIC.Service Access Points (SSAP & DSAP)
Data Unit (DU)Frame Check Sequence (FCS)
Introduction To ProfiBus DP
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20This byte identifies the end of a ProfiBus telegram and has a fixed value
of 16H.
The following functions are implemented in DP slaves and class 1
masters (see SAP descriptions above). There are only 8 mandatory slave
functions, plus the optional Set_Slave_Add function (the slave address can
usually be set via external switches). All commands noted below are
optional for class 2 master devices.Functions
DP Slave Class 1 Master Data_Exchange √√Rd_Inp √Rd_Outp √Slave_Diag √√Set_Prm √√Chk_Cfg √√Get_Cfg √Global_Control √√Set_Slave_Address
√ (Optional)Get_Master_Diag √Start_Seq √ (Optional)Download √ (Optional)Upload √ (Optional)End_Seq √ (Optional)Act_Para_Brct √ (Optional)Act_Para √ (Optional)The corresponding function acknowledgements will contain a status
parameter that may be tested to verify the success of a function request.
Possible status values are shown in the following table:
Status Value
Description OK Acknowledgement positive.IV Invalid parameters in request.NO Service in this state not possible.DS
Local FDL/PHY entity is not in logical token ring or disconnected from line.NA Negative Acknowledge – No reaction from remote station.RS Service or remote-address at remote-LSAP or remote-LSAT not activated:Remote station is no DP-Station,Remote station is not ready for these functions,Remote station is associated with another requestor,Optional service not available.RR Resources of the remote-FDL entity not sufficient or not available.UE Remote-DDLM/FDL interface error.NR No response data.TO Function timeout expired.FE Format error in request frame.RE Format error in response frame.LE Data block length too large (Upload/Download)NI Function not implemented.EA
Area too large (Upload/Download)End Delimiter (ED)DP COMMAND FUNCTIONS
Function Status
PROFIBUS-DP协议简介 一．PROFIBUS – DP用于现场层的高速数据传送。 主站周期地读取从站的输入信息并周期地向从站发送输出信息。总线循环时间必须要比主站（PLC）程序循环时间短。除周期性用户数据传输外，PROFIBUS-Dp还提供智能化设备所需的非周期性通信以进行组态．诊断和报警处理。 ①传输技术：RS－485双绞线．双线电缆或光缆。波特率从9.6K bit/s到12M bit/s。 ②总线存取：各主站间令牌传递，主站与从站间为主－从传送。支持单主或多主系统。总线上最多站点（主－从设备）数为126。 ③通信：点对点（用户数据传送）或广播（控制指令）。循环主－从用户数据传送和非循环主－主数据传送。 ④运行模式：运行．清除．停止。 ⑤同步：控制指令允许输入和输出同步。同步模式：输出同步；锁定模式：输入同步。 ⑥功能：DP主站和DP从站间的循环用户有数据传送。各DP从站的动态激活和可激活。DP从站组态的检查。强大的诊断功能，三级诊断诊断信息。输入或输出的同步。通过总线给DP从站赋予地址。通过部线对DP主站（DPM1）进行配置，每个DP从站的输入和输出数据最大为246字节。 ⑦可靠性和保护机制：所有信息的传输按海明距离HD＝４进行。DP从站带看门狗定时器（Watchdog Timer）。对DP从站的输入／输出进行存取保护。DP主站上带可变定时器的用户数据传送监视。 ⑧设备类型：第二类DP主站（DPM2）是可进行编程．组态．诊断的设备。第一类DP主站（DPM1）是中央可编程控制器，如PLC．PC等。DP从站是带二进制值或模拟量输入输出的驱动器．阀门等。 （１）PROFIBUS – DP基本特征 ①速率：在一个有着32个站点的分布系统中，PROFIBUS-DP对所有站点
Profibus DP通讯协议简单介绍 一、首先，Profibus DP通讯协议是一种单一的、一致性通讯协议，用于所有的工厂自动化和过程自动化。 这种协议使用“主-从”模式：一个设备（主）控制一个或多个其他设备（从）； 协议使用：“令牌”模式：“令牌”通过网络传递，具有令牌控制的站有权访问网络。Profibus DP以三种版本存在： DP-V0:Overall command structure循环数据交换 DP-V1：扩展到非循环数据交换等 DP-V2：进一步扩展到及时，时钟同步等。 一种单一的协议适应所有的应用 Profibus DP支持所有的DCS或控制器与单个的现场设备； 工厂设备和过程设备是直接地连接到Profibus DP； 过程自动化设备（PA），聚合在“PA簇”，通过连接器或链环连接到PROFIBUS DP； Profibus总线访问协议（第二层）对三种Profibus版本（FMS/DP/PA）均相同； 这使得通讯透明和FMS/DP/PA网络区域容易组合； 因为FMS/DP使用相同的物理介质（RS-485/FO），因此他们能组合在同一根电缆上。二、Profibus-总线访问协议的特征 混合总线访问协议： 主站间的逻辑令牌环 主从站间的主从协议 主站： 主动站在一个限定时间内（Token Hold Time）对总线有控制权。 从站： 从站只是响应一个主站的请求，他们对总线没有控制权。 三、Profibus-总线访问协议（FDL）的特点 主站或从站可以在任何时间点接入或断开，FDL将自动重新组织令牌环； 令牌调度确保每个主站有足够的时间履行它的通信任务；因此，用户必须计算全部目标令牌环的时间； 总线访问协议有能力发现有故障的站、失效的令牌、重复的令牌、传输错误和其他所有可能的网络失败。 所有信息（包括令牌信息）在传输过程中确保高度安全，以免传输错误。海明距离HD=4. 四、Profibus-令牌调度原理 在多主网络中，令牌调度必须确保每个主站有足够的时间完成他的通讯任务； 用户组织全部目标令牌循环时间（TTR）进入所有主站的通信任务账户； 每一个主站根据下列公式计算它接收令牌后完成它的通信任务的时间（TTH）: TTH=TTR-TRR TTH=持有令牌的时间 TTR=目标令牌循环时间 TRR=实际令牌循环时间 五、Profibus报文结构
profibus-DP和modbus是两种不同的通信协议。 【PROFIBUS】 PROFIBUS，是一种国际化．开放式．不依赖于设备生产商的现场总线标准。PROFIBUS传送速度可在9.6kbaud~12Mbaud范围内选择且当总线系统启动时，所有连接到总线上的装置应该被设成相同的速度。广泛适用于制造业自动化、流程工业自动化和楼宇、交通电力等其他领域自动化。PROFIBUS是一种用于工厂自动化车间级监控和现场设备层数据通信与控制的现场总线技术。可实现现场设备层到车间级监控的分散式数字控制和现场通信网络，从而为实现工厂综合自动化和现场设备智能化提供了可行的解决方案。 ★特点 Profibus作为业界应用最广泛的现场总线技术，除具有一般总线的优点外还有自身的特点，具体表现如下： （1）最大传输信息长度为255B，最大数据长度为244B，典型长度为120B。 （2）网络拓扑为线型、树型或总线型，两端带有有源的总线终端电阻。 （3）传输速率取决于网络拓扑和总线长度，从9.6Kb/s到12Mb/s不等。 （4）站点数取决于信号特性，如对屏蔽双绞线，每段为32个站点（无转发器），最多127个站点带转发器。 （5）传输介质为屏蔽/非屏蔽双绞线或光纤。
（6）当用双绞线时，传输距离最长可达9.6km，用光纤时，最大传输长度为90km。 （7）传输技术为DP和FMS的RS-485传输、PA的IEC1158-2传输和光纤传输。 （8）采用单一的总线方位协议，包括主站之间的令牌传递与从站之间的主从方式。 （9）数据传输服务包括循环和非循环两类。 【Modbus】 Modbus是由Modicon（现为施耐德电气公司的一个品牌）在1979年发明的，是全球第一个真正用于工业现场的总线协议。 ModBus网络是一个工业通信系统，由带智能终端的可编程序控制器和计算机通过公用线路或局部专用线路连接而成。其系统结构既包括硬件、亦包括软件。它可应用于各种数据采集和过程监控。 ModBus网络只有一个主机，所有通信都由他发出。网络可支持247个之多的远程从属控制器，但实际所支持的从机数要由所用通信设备决定。采用这个系统，各PC可以和中心主机交换信息而不影响各PC执行本身的控制任务。 ★特点 Modbus具有以下几个特点： （1）标准、开放，用户可以免费、放心地使用Modbus协议，不需要交纳许可证费，也不会侵犯知识产权。目前，支持Modbus的厂家超过400
竭诚为您提供优质文档/双击可除profibus通讯协议和uss 篇一：pRoFibus和uss通信 https://www.doczj.com/doc/7213320556.html,s在s7-200与变频器的通信中实现自由口通信 1引言 计算机及通讯技术已成为工业环境中大部分解决方案 的核心部分，其在系统中的比重正在迅速增加。在一个自动化系统中，交、直流调速器不仅仅作为一个单独的执行机构，而是随着其不断的智能化，它们相互之间及同控制系统之间可以通过各种通讯方式结合成一个有机的整体。西门子变频器uss自由口通信以其通信质量高、成本低廉在自动化系统得到了广泛的应用。本文以uss自由口通信在石油钻机电气传动系统中的实际应用为例，对自由口使用的地址分配，通信程序实现进行了较详细的分析，该思路不仅用于plc来保证通信质量，对于用高级语言在pc实现的通信程序编制、提高通信的可靠性都具有一定的借鉴意义。 2uss通信 2.1uss概况 西门子交、直流调速器采用的uss通讯协议是西门子公
司为传动系统开发的通讯协议，可支持交直流驱动器同pc 或plc之间建立通讯联接，适用于规模较小的自动化系统。有以下特点: (1)用单一的、完全集成的系统来解决自动化问题。所 有的西门子交、直流驱动器都可采用uss协议作为通信链路，原先的驱动器间是孤立的，仅有极少量通过硬件电路反馈信号。 (2)数字化的信息传递，提高了系统的自动化水平及运 行的可靠性，解决了模拟信号传输所引起的干扰及漂移问题。 (3)其通信介质采用Rs-485屏蔽双绞线，最远可达1000m，因此可有效地减少控制电缆的数量，原系统中需要20芯控 制电缆一般在4根以上，现在只需工作电源就可以，从而可以大大减少开发和工程费用，提高可靠性。 (4)通讯速率较高，可达187.5kbps。对于有5个变频器，每个调速器有六个过程数据需刷新的系统，plc的典型扫描 周期为几百毫秒。 (5)它采用与pRoFibus相似的操作模式，总线结构为单主站、主从存取方式。报文结构具有参数数据与过程数据，前者用于改变调速器的参数，后者用于快速刷新调速器的过程数据，如启动停止、逻辑锁定、速度给定、力矩给定等。具有极高的快速性与可靠性。 2.2西门子uss通信协议[1>
PROFIBUS协议芯片ASPC2R/STE2A (1) ASICs芯片ASPC 2 是一种用于主站的智能通信芯片，支持PROFIBUS-DP和PROFIBUS-FMS 协议。通过段耦合器也可接PROFIBUS-PA。这种芯片可使可编程序控制器、个人计算机、驱动控制器、人机接口等设备减轻通信任务负担。IM 180接口模板使用的就是ASPC 2。ASPC 2 最大数据传输速率12Mbit/s。 (2) ASPC 2 采用100管脚的MQFP封装。如果用于本征安全场合，还需要一个外界信号转换器才能接到PROFIBUS-PA上。
(3) ASPC 2 可完成信息报文、地址码、备份数据序列的处理。ASPC 2 与相关FRIMWARE可支持PROFIBUS-FMS/DP的全部协议。ASPC 2可寻址1M字节的外部信息报文存储器。总线存取驱动由硬件完成。APSC 2 需要一个独立的微处理器和必要FRIMWARE一起工作。ASPC 2可以方便连接到所有标准类型的微处理器上。 (4) ASPC 2 主要技术指标： ·▲支持PROFIBUS-DP、-FMS、-PA协议。 ·▲最大数据传输速率12Mbit/s。 ·▲最多可连接125个ACTIVE/PASSIVE站点。 ·▲100管脚的MQFP封装。 ·▲16位数据线。2个中断线。 ·▲可寻址1M字节的外部信息报文存储器。 ·▲功能支持：Ident、request FDL status、SDN、SDA、SRD、SDR with distribution database、SM。 ·▲5VDC供电，最大功率损耗0.8W。 (5) FRIMWARE: 用于ASPC 2 的FRIMWARE可完成所有协议处理和主站应具有的功能要求。用于PROFIBUS-DP的FRIMWARE提供给许可证机构内部的设备制造商。 (6) 使用ASPC 2 的PROFIBUS-DP主站接口框图, 见图5-8。
Profibus-DP协议智能电表 张小莉 第一章 Profibus-DP协议概述 本章节简要介绍了Profibus-DP协议，用户若熟悉本节内容，可以直接阅读第二章节仪表的通讯配置。 1.1 Profibus-DP简介 Profibus是唯一集成H1(过程)和H2（工厂自动化）的现场总线解决方案，是一种国际化的、开放的现场总线标准，它也是国际标准IEC61158中8种现场总线之一。Profibus可以将数字自动化设备从低级（传感器/执行器）到中间级执行级（单元级）分散开来。根据应用特点和用户不同的需要， Profibus 提供了3种兼容版本通信协议：FMS 、PA和DP 。 Profibus-DP用于自动化系统中单元级控制设备与分布式I/O的通讯。 Profibus-DP使用第1层、第2层和用户接口层、第3~7层未使用，这种精简的结构确保了高速数据传输。直接数据链路映像程序DDLM提供对第2层的访问。用户接口规定了设备的应用功能、Profibus-DP 系统和设备的行为特性。Profibus-DP特别适合于PLC与现场分级式I/O设备之间的通讯。主站之间的通讯为令牌方式，主站与从站之间为主从方式，以及这两种方式的混合。 1.2 Profibus-DP物理层 1.2.1 传输介质 PROFIBUS-DP传输技术采用的是RS485传输，其传输介质可以选择型式A和型式B两种导线，A为屏蔽双绞线，B为普通双绞线。但在EN50 170标准中规定为型式A导线，型式A比型式B有较大的扩展长度，见表1。 表1：Line A Line B说明 1.2.2 传输距离 标准Profibus-DP支持以下传输速率：（单位：kbps）9.6、19.2、31.25、45.45、93.75、187.5、500、1500、3000、6000、12000。每个DP从站的输入数据和输出数据最大为244B，使用屏蔽双绞电缆时最长通讯距离为9.6km（需要增加中继），使用光缆时最长为90km。
BusWorks TM 900PB Series ProfiBus/RS485 Network I/O Modules Technical Reference INTRODUCTION TO PROFIBUS DP ACROMAG INCORPORATED Tel: (248) 624-1541 30765 South Wixom Road Fax: (248) 624-9234 P.O. BOX 437 Wixom, MI 48393-7037 U.S.A. Copyright 2002, Acromag, Inc., Printed in the USA. Data and specifications are subject to change without notice. 8500-698-A02M000
Introduction To ProfiBus DP __________________________________________________________________ 2INTRODUCTION TO PROFIBUS DP ABOUT PROFIBUS.…………………………………………… 3PROFIBUS DP SLAVE STATE MACHINE..………………… 7Power ON/Reset State………………………………….. 7Parameterization State…………………………………. 7I/O Configuration State…………………………………. 7Data Exchange State……………………………………. 8Fail Safe Operation…………………..………………….. 8Watchdog……………………………..………………….. 9GSD FILES……………………………………………………… 10REQUIRED SOFTWARE…..………………..………………… 13TYPES OF TRANSMISSION………………..………………… 14SRD Send and Request Data w/Acknowledge…….. 14SDN Send Data w/No Acknowledge………………….. 14PROFIBUS DP DATA CHARACTER FORMAT……………. 14ProfiBus Data Error Checking………….…………….. 15PROFIBUS TELEGRAM STRUCTURE…………………….. 15Start Delimiter……………………………………………. 16Length Of Telegram…………………………………….. 18Destination Address & Source Address…………….. 18Function Code Or Frame Control…………………….. 18Service Access Points………………………………….. 19Data Unit………………………………………………….. 19Frame Check Sequence………………………………… 19End Delimiter…………………………………………….. 20DP COMMAND FUNCTIONS…………………………………. 20Function Status………………………………………….. 20OPERATING STATES AND APPLICABLE FUNCTIONS.... 21Initial Power ON/Reset………………………………….. 21Set_Slave_Add Telegram………………………… 22Parameterization……..………………………………….. 23Set_Prm Telegram…………………………………. 24I/O Configuration……..………………………………….. 26Chk_Cfg Telegram…………………………………. 26Get_Cfg Telegram…………………………………. 27Diag_Data Telegram………………………………. 27Data Exchange State..………………………………….. 33Data_Exchange Telegram……..…………………. 33Read_Inp Telegram……..…………………………. 33Read_Outp Telegram…………..…………………. 34Global_Control Services..……..…………………. 34Use Of Freeze..……..……..…………………. 35Use Of Sync/Unsync.……..…………………. 35BUS TIMING (36) This information is provided as a service to our customers and to others interested in learning more about Profibus. Acromag assumes no responsibility for any errors that may occur in this document, and makes no commitment to update or keep this information current. Be sure to visit Acromag on the web at https://www.doczj.com/doc/7213320556.html,. Windows? is a registered trademark of Microsoft Corporation. Modbus? is a registered trademark of Modicon, Incorporated. TABLE OF CONTENTS
MCGS_TCP通过MODBUS协议转换和DP通讯说明 一，方案说明： 本方案主要是使用PM-160模块将modbus协议转换成为DP总线Profibus DP 总线协议，完成昆仑通态触摸屏通过232或者485和Profibus DP的控制设备通讯。二，硬件连接： PM-160硬件外观 硬件连接：
三，软件设置： 1，昆仑通态触摸屏端组态设置，设备窗口中设备组态如下图所示： 通用串口父设备0设置 注意：如果使用232通讯，串口端口号应该为0-COM1 如果使用485通讯，串口端口号应该为0-COM2 通讯波特率，数据位，停止位，校验位，需要和PM-160里面设置一致，默认的 参数是9600, 8位，1位，无校验。
设备0-MODBUS –RTU设置，只需设置设备地址，和PM-160实际配置地址一致即可，默认为1. 添加通道，注意无论是3区和4区的数据，都需要从1通道开始添加。3区读取数据，对应DP总线中的输入，4区写数据，对应DP总线中的输出。
2,PM-160的配置软件是PMG-123，软件中具体设置如下：首先将PM-160侧边的两个拨码2打到ON，启动配置模式， 接线图定义 主要设置子网：协议内型，MODBUS从站 通迅波特率：9600 数据位：8位 奇偶校验位：无 停止位: 1位 从站地址： 1 通迅传输模式：RTU 通迅接口：根据触摸屏设置选择232或者485 注意：以上设置必须和触摸屏中父设备和子设备设置相同。
至此完成了MCGS触摸屏通过PM-160将MODBUS转换为PROFIBUS协议通迅建立完成，只需要客户在DP总线上配置的输入起始地址和MODBUS3区01地址对应，输出其实地址和MODBUS4区01地址对应即可。
竭诚为您提供优质文档/双击可除profibus协议报文格式 篇一：profibus协议报文说明 1、通信端口参数 支持的波特率： 2、报文格式 3）sd3:固定8字节数字域 篇二：profibus协议 pRoFibus协议 20xx-01-2118:03 Rs485接口 （1）pRoFibus是一种国际化．开放式．不依赖于设备生产商的现场总线标准。广泛适用于制造业自动化．流程工业自动化和楼宇．交通电力等其他领域自动化。 （2）pRoFibus由三个兼容部分组成，即pRoFibus－dp （decentralizedperiphery）．pRoFibus－pa （processautomation）．pRoFibus-Fms(Fieldbus messagespecification)。 （3）pRoFibus–dp:是一种高速低成本通信，用于设备
级控制系统与分散式i／o的通信。使用pRoFibus－dp可取代办24Vdc或4－20ma信号传输。 （4）poRFibus－pa：专为过程自动化设计，可使传感器和执行机构联在一根总线上，并有本征安全规范。 （5）pRoFibus－Fms：用于车间级监控网络，是一个令牌结构．实时多主网络。 （6）pRoFibus是一种用于工厂自动化车间级监控和现场设备层数据通信与控制的现场总线技术。可实现现场设备层到车间级监控的分散式数字控制和现场通信网 络，从而为实现工厂综合自动化和现场设备智能化提供了可行的解决方案。 （7）与其它现场总线系统相比，pRoFibus的最大优点在于具有稳定的国际标准en50170作保证，并经实际应用验证具有普遍性。目前已应用的领域包括加工制造．过程控制和自动化等。pRoFibus开放性和不依赖于厂商的通信的设想，已在10多万成功应用中得以实现。市场调查确认，在德国和欧洲市场中pRoFibus占开放性工业现场总线系统的市场超过40％。pRoFibus有国际著名自动化技术装备的生产厂商支持，它们都具有各自的技术优势并能提供广泛的优质新产品和技术服务。 《pRoFibus协议结构》 pRoFibus协议结构是根据iso7498国际标准，以开放式
PROFIBUS协议 2010-01-21 18:03 RS485接口 （1） PROFIBUS是一种国际化．开放式．不依赖于设备生产商的现场总线标准。广泛适用于制造业自动化．流程工业自动化和楼宇．交通电力等其他领域自动化。 （2） PROFIBUS由三个兼容部分组成，即PROFIBUS－DP（ Decentralized Periphery）．PROFIBUS －PA（Process Automation ）．PROFIBUS-FMS (Fieldbus Message Specification )。 （3） PROFIBUS–DP: 是一种高速低成本通信，用于设备级控制系统与分散式I／O的通信。使用PROFIBUS－DP可取代办24VDC或4－20mA信号传输。 （4） PORFIBUS－PA：专为过程自动化设计，可使传感器和执行机构联在一根总线上，并有本征安全规范。 （5） PROFIBUS－FMS：用于车间级监控网络，是一个令牌结构．实时多主网络。 （6） PROFIBUS是一种用于工厂自动化车间级监控和现场设备层数据通信与控制的现场总线技术。可实现现场设备层到车间级监控的分散式数字控制和现场通信网 络，从而为实现工厂综合自动化和现场设备智能化提供了可行的解决方案。 （7）与其它现场总线系统相比，PROFIBUS的最大优点在于具有稳定的国际标准EN50170作保证，并经实际应用验证具有普遍性。目前已应用的领域包括加工制造． 过程控制和自动化等。PROFIBUS开放性和不依赖于厂商的通信的设想，已在10多万成功应用中得以实现。市场调查确认，在德国和欧洲市场中 PROFIBUS占开放性工业现场总线系统的市场超过40％。PROFIBUS有国际著名自动化技术装备的生产厂商支持，它们都具有各自的技术优势并能提供广泛的优质新产品和技术服务。 《PROFIBUS 协议结构》 PROFIBUS协议结构是根据ISO7498国际标准，以开放式系统互联网络（Open System Interconnection-SIO）作为参考模型的。该模型共有七层。 （1）PROFIBUS－DP：定义了第一．二层和用户接口。第三到七层未加描述。用户接口规定了用户及系统以及不同设备可调用的应用功能，并详细说明了各种不同PROFIBUS－DP设备的设备行为。 （2）PROFIBUS－FMS：定义了第一．二．七层，应用层包括现场总线信息规范（Fieldbus Message Specification - FMS）和低层接口(Lower Layer Interface －LLⅠ)。FMS包括了应用协议并向用户提供了可广泛选用的强有力的通信服务。LLⅠ协调不同的通信关系并提供不依赖设备的第二层访问接口。 （3）PROFIBUS－PA：PA的数据传输采用扩展的PROFIBUS－DP协议。另外，PA还描述了现场设备行为的PA行规。根据IEC1158－2标准，PA的传输技术可确保其本征安全性，而且可通过总线给现场设备供电。使用连接器可在DP上扩展PA网络。 注：第一层为物理层，第二层为数据链路层，第三－六层末使用，第七层为应用层。《PROFIBUS传输技术》 PROFIBUS提供了三种数据传输类型： （1）用于DP和FMS的RS485传输。 （2）用于PA的IEC1158－2传输。 （3）光纤
2.2 PROFIBUS 通讯协议 对于调速驱动装置，根据变速驱动行规，在周期型通道中传输的数据结构被定义为参数过程数据对象PP0(Parameter Process Object) [2]。这个通道经常被称为标准通道，其中包含有用的用户数据。可用的数据结构分为两个部分且能用报文分别传送：过程通道PZD 部分、参数通道PKW 部分，具体的协议报文结构如图2 所示。 变速驱动行规对PPO 的结构、长度作了更具体的规定，常用的参数过程数据对象PPO 一共有5 种类型，按照可用数据有无参数通道及过程通道的数据字的多少来划分：（1）可用数据有数据区而无参数区，有两字或六个字的过程数据，如PPO3 和PP04。（2）可用数据有参数区和数据区，且有两个字、六个字或是个字的过程数据，如PPO1、PPO2、PPO5。常用的PPO 类型如表2 所示。选用那种类型的PP0，取决于在硬件组态中的设置。过程数据在传动系统中总是以最高优先级进行传送和处理，它主要传送传动装置的状态信息和控制信息。参数数据运行存取传动系统的所有参数。因而，它能够在不影响过程数据传输性能的情况下，从上一级系统调用参数值、诊断值、故障信号等。 PKW 区说明参数数值（PKW）的数据接口处理方式。PKW 接口并非物理意义的接口，而是一种通讯机理。这一机理确定了参数在两个通讯伙伴之间(如PLC 和变频器之间)的传输方式。PKW 参数区一般包含4 个字。前两个字（PKE 和IND）的信息是关于主站请求任务（任务识别标记ID）和从站应答响应（应答识别标记ID）的报文。PKW 的后两个字（PWE1和PWE2）用来读写具体的参数数值。 PKW 参数通道的第一个字是参数标识符PKE。位0 到10（PNU）包括所请求的参数号，它决定所要执行的参数读写任务访问的是数组参数中的哪一个元素。位11（SPM）是用来参数变更报告的触发位。位12 到位15（AK）包括任务标识ID 和应答标识ID. PKW 参数通道的第二个字变址IND 的位12 到15 位是参数号PNU 的扩展页号，它和参数标识符基本参数号PNU 共同产生完整的传动装置参数号。变址IND 的0 到7 位为带数组的参数寻址提供数组下标，决定访问数组参数的哪一个元素。 第三和第四字为参数数值（PWE）。参数值总是以双字来传送，在PPO 报文中，一次只能传送一个参数值，由PWE1(高位字)和PWE2（低位字）共同组成一个32 位参数数值。当用PWE2 传送一个16 位参数值，必须在DP 主站中设置高位字PWE1 为零。 利用PKW 参数通道修改驱动装置参数必须遵守以下规则：（1）一个任务或一个应答仅能涉及一个参数。（2）主站必须重复地发送任务报文直到从从站那里得到相应的应答报文。主站通过对应答识别ID、参数号、变址下标和参数值的处理识别任务的应答。（3）完成的任务必须送出一个报文，对于应答也一样。（4）在应答报文中重复的实际值总是当前的最新值。（5）如果在周期工作中不需要PKW 参数通道的信息而只需要PZD 过程通道的信息，则任务ID 被发布为“无任务（用0 表示）”。 过程通道PZD 区是为监测和控制调速驱动装置而设计的，在DP 主站和从站中收到的PZD 报文总是以最高的优先级处理，即处理PZD 过程通道的优先级高于处理参数通道
新建 文本文档 唐济扬：《PROFIBUS总线存取协议》 （１） 三种PROFIBUS(DP．FMS．PA)均使用一致的总线存取协议。该协议是通过OSI参考模型第二层（数据链路层）来实现的。它包括了保证数据可靠性技术及传输协议和报文处理。 （２） 在PROFIBUS中，第二层称之为现场总线数据链路层（Fieldbus Data Link - FDL）。介质存取控制（Medium Access Control - MAC）具体控制数据传输的程序，MAC必须确保在任何一个时刻只有一个站点发送数据。 （３） PROFIBUS协议的设计要满足介质控制的两个基本要求： ①． 在复杂的自动化系统（主站）间的通信，必须保证在确切限定的时间间隔中，任何一个站点要有足够的时间来完成通信任务。 ②． 在复杂的程序控制器和简单的I/O设备（从站）间通信，应尽可能快速又简单地完成数据的实时传输。 因此，PROFIBUS总线存取协议，主站之间采用令牌传送方式，主站与从站之间采用主从方式。 （４） 令牌传递程序保证每个主站在一个确切规定的时间内得到总线存取权（令牌）。在PROFIBUS中，令牌传递仅在各主站之间进行。 （５） 主站得到总线存取令牌时可与从站通信。每个主站均可向从站发送或读取信息。因此，可能有以下三种系统配置： ① ．纯主－从系统 ②．纯主－主系统 ③．混合系统 （６） 以一个由３个主站．７个从站构成的PROFIBUS系统为例。３个主站之间构成令牌逻辑环。当某主站得到令牌报文后，该主站可在一定时间内执行主站工作。在这段时间内，它可依照主－从通讯关系表与所有从站通信，也可依照主－主通讯关系表与所有主站通信。 （７） 在总线系统初建时，主站介质存取控制MAC的任务是制定总线上的站点分配并建立逻辑环。在总线运行期间，断电或损坏的主站必须从环中排除，新上电的主站必须加入逻辑环。 （８） 第二层的另一重要工作任务是保证数据的可靠性。PROFIBUS第二层的数据结构格式可保证数据的高度完整性。 （９）PROFIBUS在第二层按照非连接的模式操作，除提供点对点 逻辑数据传输外，还提供多点通信，其中包括广播及选择广播功能。 第 1 页
PROFIBUS System Description
Technology and Application
Introduction
The field of industrial communications is continuing to develop at an astonishing pace with the result that the field of automation technology is constantly changing. Initially, automation focused exclusively on production, but now it is part of a network that covers service and maintenance, warehousing, resource optimization and the provision of data for MES and ERP systems in addition to the actual task of automation. Fieldbus technology, which has facilitated migration from centralized to decentralized automation systems and supports the use of distributed intelligence, has been the driving force behind this development. Ethernet-based communication systems link automation technology with information technology, thus implementing consistent communication from the field level to the corporate management level. Standardized solutions can be found in PROFIBUS and PROFINET, which provide absolute consistency and are highly applicationoriented. With its standard protocol, PROFIBUS takes in all subprocesses found in production and process automation, including safety-related communication and drive applications, thereby providing the ideal basis for ensuring horizontal consistency within an automation system. PROFINET also features a standard protocol which, in addition to horizontal communication, also supports vertical communication, thereby linking the field level with the corporate management level. Both communication systems are, therefore, able to facilitate cross-networked, integrated solutions that are optimized for the automation tasks concerned. Since 1989, PROFIBUS has developed into a worldwide leading fieldbus system used in machine and production plant automation. The main reason why PROFIBUS stands out from other fieldbus systems is because it offers such an extraordinary breadth of applications. Application specific requirements have been integrated into application profiles, and these applications have been combined as a whole to create a standardized and open communication system. The use of open standards instead of proprietary solutions ensures long-term compatibility and expandability, which forms the basis for implementing comprehensive investment protection for users and manufacturers. This is a very important concern of PROFIBUS & PROFINET International. Established worldwide support offers members longterm perspectives. With well over 30 million devices (as of the end of 2009), PROFIBUS is currently present in every branch of industrial automation and makes an important contribution to the economic and technological success of the companies.
PROFIBUS System Description
I
Profibus-DP规（草案）
1 围和目的 (4) 1.1 目的 (4) 1.2 围 (4) 1.3 术语 (4) 1.4 概述 (6) 2 规性引用文件 (7) 3 物理层定义 (7) 3.1 RS-485物理传输方式 (7) 3.2 电气特性 (7) 3.3 总线连接器 (7) 3.4 总线电缆 (8) 3.5 接地，屏蔽 (8) 3.6 总线终端器 (9) 3.7 物理层和介质冗余 (9) 4 链路层定义 (10) 4.1 数据传输功能 (10) 4.2 帧结构 (11) 4.2.1 帧字符（UART字符） (11) 4.2.2 传输规则 (11) 4.2.3 位同步 (12) 4.3 帧格式 (12) 4.3.1 无数据字段的固定长度的帧SD1 (12) 4.3.2 有数据字段的固定长度的帧SD3 (13) 4.3.3 有可变数据字段长度的帧SD2 (13) 4.3.4 令牌帧SD4 (14) 4.4 循环和系统响应时间 (15) 4.4.1 令牌循环时间(Token Cycle Time) (15) 4.4.2 报文循环时间(Message Cycle Time) (15) 4.4.3 系统反应时间(System Reaction Times) (16) 5 PROFIBUS-DP通信模型 (17) 5.1 协议结构 (17) 5.2 通信关系 (19) 5.3 功能概述 (21) 6 PROFIBUS-DP应用层实现 (23) 6.1 Prifibus DP从站状态机 (23) 6.2 Prifibus DP从站初始化报文过程 (23) 6.2.1 检查从站是否存在 (23) 6.2.2 初始化前的诊断信息 (23) 6.2.3 设置从站参数 (24) 6.2.4 校验组态数据 (24) 6.2.5 初始化后的诊断信息 (25) 6.2.6 数据交换 (25) 6.2.7 从站参数化中Watchdog时间因子 (26) 6.3 保护测控装置数据在Profibus-DP中的映射 (26)