SIMATIC NET. DP Base Programming Interface for CP 5613/CP Preface, Contents. Basic Steps in Creating a DP Application 1

Transcription

1 SIMATIC NET DP Base Programming Interface for CP 5613/CP 5614 Manual Preface, Contents Basic Steps in Creating a DP Application 1 Overview of PROFIBUS DP 2 Overview of the DP Base Interface 3 Description of the DP Functions, Data, and Error Codes 4 Description of the Sample Programs 5 FAQ (Frequently Asked Questions) 6 Glossary, Index C79000-G8976-C Release 04/2009

2 Classification of Safety-Related Notices This document contains notices which you should observe to ensure your own personal safety, as well as to protect the product and connected equipment. These notices are highlighted in the manual by a warning triangle and are marked as follows according to the level of danger:! Danger indicates that death or severe personal injury will result if proper precautions are not taken.! Warning indicates that death or severe personal injury can result if proper precautions are not taken.! Caution with warning triangle indicates that minor personal injury can result if proper precautions are not taken. Caution without warning triangle indicates that damage to property can result if proper precautions are not taken. Notice indicates that an undesirable result or status can occur if the relevant notice is ignored. Note highlights important information on the product, using the product, or part of the documentation that is of particular importance and that will be of benefit to the user. Copyright Siemens AG, 1999 to 2009, All rights reserved The reproduction, transmission or use of this document or its contents is not permitted without express written authority. Offenders will be liable for damages. All rights, including rights created by patent grant or registration of a utility or design, are reserved. Siemens AG Automation and Drives Industrial Communication Postfach 48 48, D Nuernberg Siemens Aktiengesellschaft 2 Disclaimer We have checked the contents of this manual for agreement with the hardware and software described. Since deviations cannot be precluded entirely, we cannot guarantee full agreement. However, the data in this manual are reviewed regularly and any necessary corrections included in subsequent editions. Suggestions for improvement are welcome. C79000-G8976-C Siemens AG 1999 to 2009 Subject to technical change. Printed in the Federal Republic of Germany

3 Trademarks SIMATIC, SIMATIC NET and SINEC are registered trademarks of Siemens AG. Third parties using for their own purposes any other names in this document which refer to trademarks might infringe upon the rights of the trademark owners. Safety Instructions Regarding your Product Before you use the product described here, read the safety instructions below thoroughly. Qualified Personnel Only qualified personnel should be allowed to install and work on this equipment. Qualified persons are defined as persons who are authorized to commission, to ground, and to tag circuits, equipment, and systems in accordance with established safety practices and standards. Correct Usage of Hardware Products Please note the following regarding the correct usage of hardware products: Caution This device and its components may only be used for the applications described in the catalog or the technical description, and only in connection with devices or components from other manufacturers which have been approved or recommended by Siemens. This product can only function correctly and safely if it is transported, stored, set up, and installed correctly, and operated and maintained as recommended. Before you use the supplied sample programs or programs you have written yourself, make certain that no injury to persons nor damage to equipment can result in your plant or process. EU Directive: Do not start up until you have established that the machine on which you intend to run this component complies with the directive 2006/42/EEC. C79000-G8976-C

4 Correct Usage of Software Products Please note the following regarding the correct usage of software products: Caution This software may only be used for the applications described in the catalog or the technical description, and only in connection with devices or software products from other manufacturers which have been approved or recommended by Siemens. Before you use the supplied sample programs or programs you have written yourself, make certain that no injury to persons nor damage to equipment can result in your plant or process. Prior to Startup Before putting the product into operation, note the following warning: Caution Prior to startup you must observe the instructions in the relevant documentation. For ordering data of the documentation, please refer to catalogs or contact your local Siemens representative. 4 C79000-G8976-C139-09

5 Preface Preface Purpose of the Manual This manual supports you when creating DP user programs for the "DP Base Programming Interface", the programming interface of the CP 5613/CP It provides you with a comprehensive overview. The structure of DP user programs and the individual language elements are explained. It is assumed that you are familiar with writing user programs in the "C" programming language in Windows. How the SIMATIC CPs are named in this manual Some SIMATIC CPs have one PROFIBUS connector and can be operated either as a DP master or DP slave; these are: CP 5603, CP 5613 A2, CP Unless stated otherwise, these are called "CP 5613" in this document. Other SIMATIC CPs have two PROFIBUS connectors and can therefore be operated both as a DP master or/and as a DP slave; these are: CP 5614 A2, CP Unless stated otherwise, these are called "CP 5614" in this document. Scope of this Manual Recommendation This manual is valid as of the CD "SIMATIC NET PC Software, Edition 2008, Service Pack 2". This manual is valid for the following communications processors: CP 5603, CP 5613 A2, CP 5614 A2, CP 5623, CP 5624 Read the following chapters to familiarize yourself with PROFIBUS DP, the DP Base programming interface, and the methods of creating a user program: C79000-G8976-C

6 Preface Chapter Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Content Explains step-by-step how to create your DP user program. Provides you with an overview of PROFIBUS DP. Provides an overview of the DP Base programming interface and outlines its advantages. Describes the function calls of the DP Base programming interface and the mechanisms for accessing the dual-port RAM. Describes the supplied sample programs. Provides useful information on the general aspects of writing user programs. Structure of the Documentation You will find information on the use of this product in the following sources: Supplied paper documentation Text, PDF, and HTML files of the SIMATIC NET CDs (some available as bound volumes) Internet ( SIMATIC NET Product Catalog "IK PI" Certification The products and systems listed in this document are manufactured and marketed using a quality management system complying with DIN ISO 9001 and certified by DQS (certificate registration no. 2613). The DQS certificate is recognized in all IQNet countries (Reg. No.: 2613). 6 C79000-G8976-C139-09

7 Contents Contents 1 Basic Steps in Creating a DP Application Overview of PROFIBUS DP Where Does PROFIBUS DP Fit In? The Master-Slave-Concept of PROFIBUS DP DP Communication Mechanisms Cyclic Polling by the Master Acyclic Services and Alarms CP 5613 Communications Processor CP 5614 Communications Processor The Transfer Software The Configuration for the Transfer Software Access to Process Data Startup and Operational Phase of a DP System Modes of the DP Master How a DP Master Starts Up How a DP Master Shuts Down Separation of the Slave Data from the DP Master User Program Reliability of DP Control Frames to One or More Slaves The Importance of Configuration DP-V1 as an Extension of DP Overview of the DP Base Interface Ways of Accessing the CP 5613/CP 5614 Communications Processor Special Features of the CP 5613/CP Hardware and Software Events Fast Logic Timeout Monitoring Constant Bus Cycle Time Mode Access to Operating Data in the Dual-port RAM How Does a DP Master User Program Access Process Data? Reading DP Slave Input Data Reading DP Slave Diagnostic Data Writing DP Slave Output Data Coordination in Multi-Thread Operation How Does a DP Master User Program Recognize Changed Input Data and New Diagnostic Data? Recognizing Changes in the DP Slave Input Data C79000-G8976-C

8 Contents Recognizing New DP Slave Diagnostic Data Typical Sequences for the Master of the CP 5613/CP Initialization Phase, Productive Operation, and Shutdown Phase in DP Master Operation DP Master Mode Polling DP Master Operation with Hardware and Software Events Acyclic Services Without Using Software Events Acyclic Services Using Software Events Properties of the DP Slave on the CP 5613/CP Two Modes of the DP Slave on the CP 5613/CP Basic Structure of a DP Slave User Program Typical Sequences in the "Simple Slave" Mode Typical Sequences in the "Dynamic Slave" Mode without Software Event Typical Sequences in the "Dynamic Slave" Mode with Software Event Multiple Protocols, DP User Programs, CPUs Description of the DP Functions, Data, and Error Codes List of Functions of the CP 5613 and CP Overview of the Functions DP_start_cp DP_reset_cp DP_open DP_get_pointer DP_release_pointer DP_close DP_get_err_txt DP_set_mode DP_slv_state DP_read_slv_par DP_global_ctrl DP_ds_read DP_ds_write DP_fetch_alarm DP_alarm_ack DP_get_actual_cfg DP_enable_event DP_disable_event DP_get_result DP_get_cref DP_init_sema_object DP_delete_sema_object DP_fast_logic_on DP_fast_logic_off DP_watchdog DP_write_trc DP slave functions Overview of the Slave Module Functions DPS_open DPS_close DPS_start DPS_stop DPS_get_baud_rate C79000-G8976-C139-09

9 Contents DPS_get_gc_command DPS_get_state DPS_set_diag DPS_get_ind Structure Elements of DPS_C2_INITIATE_REQ DPS_set_resp DPS_calc_io_data_len Access to the Process Image of the CP 5613/CP Reading the Input Data of a DP Slave Reading the Diagnostic Data of a DP Slave Writing the Output Data of a DP Slave Checking the Slaves for Changed Data Querying the State of a DP Slave Querying Information about the DP Master Querying the Current Bus Parameters of the Master Querying Information about DP Slaves Reading PROFIBUS Statistical Data Querying the Fast Logic Status Reading and Triggering User Watchdog in the Dual-Port RAM Activating/Deactivating the Generation of Hardware Events Sending Data with the CP 5614 as DP Slave Receiving Data with the CP 5614 as DP Slave Sending Diagnostic Data with the CP 5614 as DP Slave Using the Constant Bus Cycle Time Mode Typical Phases in the Constant Bus Cycle Time Mode Checking the Life Counter Error Handling Entries in the error_decode, error_code_1 and error_code_2 structure elements in Error Class DP_ERROR EVENT Error Codes Formats of the Slave Data Formats of the Slave Diagnostic Data Overview of the Entire Structure Format of the Diagnostic Data Header Format of the Device-Related Diagnostic Data (Standard DP Slave) Format of the Device-Related Diagnostic Data (Slaves with DP-V1 Extensions) Format of ID-Related Diagnostics Format of Channel-Related Diagnostics Format of the Revision Number Format of the Slave Parameter Data Structure of the General Slave Parameters Structure of the Parameter Assignment Data Structure of the Configuration Data Meaning of GSD Files Description of the Sample Programs Starting the Simple Sample Program Starting the Complete Sample Program Starting the "Fast Logic" Sample Program C79000-G8976-C

10 Contents 5.4 Starting the Transfer Sample Program for the CP Configuring the Transfer for the CP 5614 Transfer Sample Program FAQ (Frequently Asked Questions) FAQs about the Range of Functions of the Product FAQs about Structuring the DP User Program FAQ Check List for Programmers FAQs about Debugging and Starting Up Your Program FAQs Miscellaneous Programming Questions Glossary Index C79000-G8976-C139-09

11 Basic Steps in Creating a DP Application 1 This chapter recommends a step-by-step procedure for creating a DP user program based on the DP programming interface of the CP 5613 and CP 5614 known as "DP Base". The steps begin with the basics of PROFIBUS DP and are completed when you test your application. The DP Base programming interface allows direct access to the DP process image in the dual-port RAM of the CP 5613/CP The DP Base programming interface is therefore not compatible with the DP programming interface of the CP 5511, the CP 5611 and the CP Since the DP Base interface is a high-speed interface, it cannot be operated at the same time as the DP interface mentioned above on a CP 5613/CP C79000-G8976-C

12 Basic Steps in Creating a DP Application Procedure The steps outlined below represent the fastest and simplest way of achieving your aims: Step Description 1 Familiarize yourself with the basic principles of PROFIBUS DP. Read the following Chapter 2 "Overview of PROFIBUS DP". 2 Familiarize yourself with the basic characteristics of the DP Base programming interface of the CP 5613 and CP Read Chapter 3 "Overview of the DP Base interface". 3 Check through the contents of the subfolder "prog" in your installation folder so that you know what it contains and the purpose of the components for the subsequent steps. The subfolder contains the following: The "readme.rtf" file with the latest additional information and most recent modifications. The C header file "dp_5613.h", dps_5614.h with the functions and data structures of the DP base interface and "5613_ret.h and 5614_ret.h" with the return codes. The import libraries "dp_base.lib" and "dps_base.lib" for linking to your DP user program. The sample programs and corresponding databases in the "examples" subfolder. 4 Now work through the source text of the sample program "ExamEasy" and read through the functions and data accesses in Chapter 4 ("Description of the DP Functions, Data, and Error Codes"). 5 Adapt the "ExamEasy" sample program to suit your plant configuration, for example by using additional or other slaves. Compile and link the sample program and try it out. You may need to extend the "ExamEasy" sample database. 6 Now work through the source text of the sample program "ExamComp", modify the program and try it out with an extended sample database. 7 If you want to use the slave functions of the CP 5614, you should also work through the "transfer" sample, modify it to your requirements and try it out with an extended sample database. 8 Please read the FAQs in Chapter 6, particularly the check list for programmers and the information on structuring your DP user program. Table continued on next page 12 C79000-G8976-C139-09

13 Basic Steps in Creating a DP Application Continued Step Description 9 Now create your own DP user program. You can use the "ExamComp" sample as a basis. 10 Test your application. Refer to the information and tips in the FAQ list in Chapter 6 and the diagnostic options described in the readme file of the SIMATIC NET CD. C79000-G8976-C

14 Basic Steps in Creating a DP Application 14 C79000-G8976-C139-09

15 Overview of PROFIBUS DP 2 This chapter will familiarize you with the basic principles of PROFIBUS DP. C79000-G8976-C

16 Overview of PROFIBUS DP 2.1 Where Does PROFIBUS DP Fit In? PROFIBUS - The Worldwide Fieldbus Strategy The trend towards reducing costs in automation engineering has meant that programmable controllers (PLCs), PCs, drives, transducers, and sensors are being networked more and more. This has resulted in greater distribution of these field devices using a fieldbus as the common communications medium for exchanging information. The demand for an open, heterogeneous fieldbus system representing a safe and long-term investment for the user has been met by PROFIBUS. PROFIBUS is a bus system for communication between programmable controllers or PCs and field devices based on the European standard EN , Volume 2. This means that both users and manufacturers can be certain about long-term investments and guarantees "openness" for all applications conforming with the standard worldwide. Created in 1989 by a consortium of companies and institutions, PROFIBUS has become the world s most popular fieldbus in discrete manufacturing and process control. It is mature, proven technology that is ideal for supporting modern automation systems. With over 25 million installed devices, it is a significant driving force for the world s production plants. By continuously enhancing the technology, PROFIBUS International has ensured that PROFIBUS remains the dominant fieldbus solution. The ongoing commitment of the world s automation major suppliers ensures that investments today are fully protected for the lifetime of any plant. PROFIBUS is unique in offering a fully integrated solution for discrete and process applications, a major benefit in the process industries where upstream, mainstream and downstream processes have to work together. Industries using PROFIBUS range from critical petrochemical operations and high volume robotic manufacturing plants, right across the spectrum to food and drink, water/waste treatment plants. Siemens has supported PROFIBUS for many years as an optimized fieldbus solution and reliable investment for the user and supplies both products and complete systems. Apart from the programmable controllers (PLCs), devices such as network components, PC communications processors, and field devices for PROFIBUS are also included in the wide range of products. The Role of the PC in PROFIBUS Apart from the trend towards distribution, the standard PC is also becoming more important as an automation tool particularly in control tasks and for plant visualization thanks to its increased performance and widespread availability. 16 C79000-G8976-C139-09

17 Overview of PROFIBUS DP The Advantages of DP PROFIBUS-DP is intended for fast data exchange in the fieldbus area. Distributed peripheral devices collect the input signals locally and transfer them via the fieldbus to the central controller in the PG/PC. In the opposite direction, the central controller sends the output data to the distributed peripheral devices. The use of PROFIBUS DP means a considerable reduction in cabling compared to previous direct wiring of components. C79000-G8976-C

18 Overview of PROFIBUS DP 2.2 The Master-Slave-Concept of PROFIBUS DP Description The master-slave concept of PROFIBUS DP describes the communications mechanisms between active and passive nodes on PROFIBUS. Distributed I/Os The distributed (peripheral) I/O allows you to use a variety of analog and digital input/output modules over PROFIBUS with a distributed configuration in close proximity to the process. This is normally abbreviated to DP. Node Types PROFIBUS DP defines two types of bus node: DP master DP masters are active nodes and control DP slaves. A distinction is made between class 1 and class 2 DP masters. DP slaves DP slaves are normally passive nodes (distributed I/O devices). A distinction is made between DP-V0 and DP-V1 slaves. 18 C79000-G8976-C139-09

19 Overview of PROFIBUS DP DP masters DP Master Class 1 A DP master class 1 communicates cyclically with the DP slaves assigned to it. Cyclic communication means that during the data transfer phase the DP master constantly sends the latest output data to the DP slaves and receives the latest input data in the response frame. With a DP master class 1, communication involves central functions such as: Assignment of parameter values and configuration of the DP slaves during startup Cyclic data transfer to the DP slaves Monitoring the DP slaves Preparing diagnostic information Depending on the application, these tasks can, for example, also be handled by a SIMATIC S7 programmable controller. In the follow text, the DP master class 1 is simply known as the DP master. DP Master Class 2 A DP master class 2 is a DP master that does not operate cyclically and is used for special functions such as online diagnostics in a PROFIBUS DP system. A DP master class 2 can also establish additional connection-oriented DPC2 communication relations with DP-V1 slaves. The DP-V1 slaves must support these DPC2 additional functions. Essentially, these include connection establishment, connection termination, reading data records, writing data records, and data transfer. This programming interface supports the DPC2 functions with the slave submodule of the CP C79000-G8976-C

20 Overview of PROFIBUS DP DP Slave A DP slave is a peripheral device from which the DP master reads in input information and to which it sends output information cyclically. There are also DP slaves that provide only input or only output information. DP slaves are generally inexpensive since passive participation on the bus is simple to implement. DP-V0 Slave A DP-V0 slave is a simple device that becomes active only when requested by the DP master. Essentially, it provides the following standard functions: Sends input data from the process to the DP master. Transfers diagnostic data to the DP master. Passes on output data from the DP master to the process. DP-V1 Slave A DP-V1 slave has the functionality of a DP-V0 slave with the following additional functions: Processing data records Data records contain special additional information specified using the slot and index. A data record can be sent via a DP master class 1 (DPC1 connection) or via a DP master class 2 (DPC2 connection). A DP master can send data records to a DP-V1 slave (write data record) or request a data record from it (read data record). Alarm handling DP-V1 slaves with alarm capability can send alarms to the master. Alarms are special diagnostic data containing important events. The DP master must acknowledge alarms by sending alarm acknowledge frames to the DP slave. Overview of the Communication Section 2.13 shows how DP-V1 communication fits in to PROFIBUS DP. Configuration Operating a DP system requires a configuration. Using configuration software, you create a "database" that is required by the DP master. Configuration tools are available for the CP 5613/CP For more detailed information on the tools (for example SIMATIC NCM PC, SIMATIC STEP 7) and on how to configure, please refer to the supplied documentation. 20 C79000-G8976-C139-09

21 Overview of PROFIBUS DP Basic Structure of a DP System The following diagram illustrates how to implement a process control with DP slaves using a PC and a CP 5613/CP 5614 communications processor. PC as DP master with CP 5613/CP 5614 PROFIBUS Process DP slaves Process input/ output data C79000-G8976-C

22 Overview of PROFIBUS DP 2.3 DP Communication Mechanisms Description Communication between a DP master (class 1) and DP slaves uses two basic mechanisms: Cyclic polling by the master This mode is the basic communication mode and is supported by all slave types (DP-V0 and DP-V1 slaves). Acyclic services and alarms This mode is an expansion of the basic communication. It is supported only by DP-V1 slaves. 22 C79000-G8976-C139-09

23 Overview of PROFIBUS DP Cyclic Polling by the Master Description The basic communication between a DP master and the distributed I/O stations takes the form of polling. Polling means that the DP master sends cyclic calls to the DP slaves assigned to it. A separate call frame is sent to each DP slave. In one polling cycle, all the operational DP slaves are addressed. The next polling cycle starts after the last slave has been addressed. This ensures that the data is up to date. Polling is handled automatically and independently by the firmware of the CP 5613/CP DP master Output data DP slaves Input data (diagnostic data when necessary) Figure 1 Schematic Representation of Polling Output Data The call frame contains the current output data that the DP slave will apply to its output ports. The data belonging to this area are specified by the DP user program. If a DP slave does not have output ports, an "empty frame" is sent to it instead. Input Data The reception of a call frame must be confirmed by the DP slave by returning a confirmation frame. The confirmation frame contains the current input data that are applied to the input ports of the DP slave. If a DP slave does not have input ports, an "empty frame" is returned instead. C79000-G8976-C

24 Overview of PROFIBUS DP Diagnostic Data Diagnostic data is generated when the slave detects an error. This is signaled to the master which then fetches the diagnostic data using a special call frame. 24 C79000-G8976-C139-09

25 Overview of PROFIBUS DP Acyclic Services and Alarms Acyclic Services Using acyclic services, the DP user program can send special data records to DP- V1 slaves or read them from the slaves. Within a DP-V1 slave, the data records are addressed using a slot number and an index. The significance of the data records is specific to the particular slave. In contrast to the input/output data, data records are not transferred cyclically but only once per job. Alarms Alarms are a particular form of diagnostic data that must be acknowledged specifically by the DP master program in contrast to standard diagnostic frames. Only DP-V1 slaves can send alarms to the DP master. When the DP master user program confirms reception of an alarm, the DP master reacts by sending an alarm acknowledge frame to the DP-V1 slave. C79000-G8976-C

26 Overview of PROFIBUS DP 2.4 CP 5613 Communications Processor Description The CP 5613 communications processor in conjunction with the DP user program that uses the functions of the DP base programming interface together form a PROFIBUS DP master class 1. CP 5613 Master user program PROFIBUS DP DP slave DP slave This DP base programming interface describes how to create your own DP master class 1 applications for the CP 5613/CP C79000-G8976-C139-09

27 Overview of PROFIBUS DP 2.5 CP 5614 Communications Processor Description The CP 5614 consists of a master section that is identical to the CP It has an additional slave submodule (piggyback module) that allows attachment to a further PROFIBUS network. With the slave submodule, a CP 5614 can be operated as a DP slave on a PROFIBUS network. The slave is controlled by a remote DP master, for example a CP 5613 or SIMATIC S7 programmable controller. Control system DP master PC Slave application PROFIBUS DP (I) CP 5614 Slave RS485 Master application Master RS485 PROFIBUS DP (II) DP slave DP slave This DP base programming interface describes how to create your own DP slave applications for the CP C79000-G8976-C

28 Overview of PROFIBUS DP The Transfer Software To operate the CP 5614 with both master and slave functionality, you can use, for example the transfer software supplied (see Section 5.4). The transfer software transfers data between the master and slave section of the CP The transfer software includes an access with which additional input, output or diagnostic jobs can be executed. Your DP user program can use this access to add extra functionality to the transfer program (in the sample program, a counter is activated on the CP 5614 slave submodule). The example illustrates how a separate transfer function with a local application can access the process image of the CP 5614 (slave and master components of the CP 5614). Control system DP master Access PC Transfer software PROFIBUS DP (I) CP 5614 Slave Master RS485 RS485 PROFIBUS DP (II) DP slave DP slave 28 C79000-G8976-C139-09

29 Overview of PROFIBUS DP The Configuration for the Transfer Software To allow you to specify the separate transfer function, a configuration tool and a configured transfer file are also shipped as an example. Using the configuration tool, you can specify how data is copied from master to slave and vice-versa. C79000-G8976-C

30 Overview of PROFIBUS DP 2.6 Access to Process Data Description A distinction must be made between two general types of process data: Input/output data and standard diagnostic data Slave data records and alarms 30 C79000-G8976-C139-09

31 Overview of PROFIBUS DP Access to Input/Output Data and Standard Diagnostic Data Input/output data and standard diagnostic data is stored on the DP master (CP 5613/CP 5614) in the dual-port RAM. This data represents the process image. There are three different data areas for each configured DP slave: Input data from the DP slave Output data to the DP slave Standard diagnostic data from the DP slave The DP user program accesses the input and output data in the dual-port RAM of the CP 5613/CP 5614 directly using C pointers; in other words without needing function calls. Standard diagnostic data can be read directly or using the function calls of the DP Base programming interface. DP application program Input data Output data Diagn. data Slave data Slave 1 Slave 2 Slave n DP master PROFIBUS Access to Slave Data Records and Alarms Slave data records are fetched or sent directly using the function calls of the DP Base programming interface. Alarms are special diagnostic data that is buffered and managed by the firmware of the CP 5613/CP The DP user program must read out this alarm data with a function call of the DP Base programming interface and acknowledge it. C79000-G8976-C

32 Overview of PROFIBUS DP 2.7 Startup and Operational Phase of a DP System Functions of the DP Master during Startup and Operation The DP master handles the following tasks independently: Initialization of the DP slaves Data transfer in the operational phase Monitoring the DP slaves Initialization of the DP Slaves The DP master can only exchange process data with the DP slaves when it has previously assigned parameter values and configured the DP slaves using special frames. The parameter assignment/configuration is contained in the database and is performed as follows: During the startup phase of the DP master. Following any temporary failure of a DP slave during the productive phase The parameter assignment frame provides the DP slave with global operating parameters (for example Group_Ident, Watchdog on/off). The configuration frame is sent after the DP slave has been assigned parameters. This frame contains the defined configuration of the DP slave. The configuration includes the number and type of input/output ports. The DP slave compares the received configuration frame with the values that it determined itself during the startup phase. If the values match, the DP slave confirms the configuration and changes to the operational phase. Data Transfer in the Operational Phase During the operational phase, the cyclic data transfer between the DP master and DP slaves takes place. The DP user program can also send acyclic data and fetch and acknowledge alarms during this phase. Monitoring the DP Slaves If a DP slave detects an error/fault, it can signal this to the DP master in the form of diagnostic data (standard diagnostic data or diagnostic data in the form of alarms). The received diagnostic data is then available on the DP master and must be evaluated by the DP user program. 32 C79000-G8976-C139-09

33 Overview of PROFIBUS DP 2.8 Modes of the DP Master Overview During communication with the DP slaves, the DP master can adopt the following four modes: OFFLINE STOP CLEAR (or AUTOCLEAR) OPERATE Each of these modes is characterized by defined actions between the DP master and the DP slaves. OFFLINE No communication between the DP master and DP slaves. This is the startup mode of the DP master. STOP In this mode, there is also no communication between the DP master and the DP slaves. In contrast to the OFFLINE mode, a DP diagnostic station (DP master class 2) can read out diagnostic information from the DP master. CLEAR All the DP slaves entered and activated in the database are assigned parameters and configured in this mode. This is followed by the cyclic data exchange between the DP master and DP slaves. In this CLEAR mode, the value 0 or empty frames are sent to all slaves with a process output; in other words, process output is deactivated. The input data of the slaves are known and can be read out. If a slave fails, for example no longer answers, the DP master automatically attempts to reassign parameters and configure the slave and return it to the polling cycle. C79000-G8976-C

34 Overview of PROFIBUS DP AUTOCLEAR The behavior of the DP master in the AUTOCLEAR mode is the same as in the CLEAR mode. With certain errors, the DP master automatically changes to the AUTOCLEAR mode; for more detailed information, refer to Section 2.10, "Reliability of DP". OPERATE The cyclic, productive data transfer to the DP slaves takes place in the OPERATE mode. In this mode, the DP slaves are addressed one after the other by the DP master. The call frame transfers the actual output data and the corresponding response frame transfers the actual input data. If a slave fails, for example no longer answers, the DP master automatically attempts to reassign parameters and configure the slave and return it to the polling cycle. 34 C79000-G8976-C139-09

35 Overview of PROFIBUS DP How a DP Master Starts Up Description When the CP 5613/CP 5614 starts up, the DP master must run through the following modes in the specified order controlled by the DP user program: OFFLINE -> STOP -> CLEAR -> OPERATE. Stage Mode Typical Actions of the DP User Program 1 OFFLINE The DP user program initiates the change to the STOP mode. Reaction: The DP master changes to the STOP mode. 2 STOP The DP user program queries the STOP mode. Once the STOP mode is reached, the program initiates the change to the CLEAR mode. Reaction: The DP master changes to the CLEAR mode. 3 CLEAR The DP user program queries the CLEAR mode. If the CLEAR mode is reached, the program can enter the output data in the process image. The program then initiates the change to the OPERATE mode. Reaction: The DP master changes to the OPERATE mode. 4 OPERATE The DP user program queries the OPERATE mode. Once the OPERATE mode is reached, productive data exchange with the slaves begins. C79000-G8976-C

36 Overview of PROFIBUS DP How a DP Master Shuts Down Description When the CP 5613/CP 5614 shuts down, the DP master must run through the modes in the following order controlled by the DP user program: OPERATE -> CLEAR -> STOP -> OFFLINE Stage Mode Typical Actions of the DP User Program 1 OPERATE The DP user program initiates the change to the CLEAR mode. Reaction: The DP master changes to the CLEAR mode. 2 CLEAR The DP user program queries the CLEAR mode. Once the CLEAR mode is reached, the program initiates the change to the STOP mode. Reaction: The DP master changes to the STOP mode. 3 STOP The DP user program queries the STOP mode. Once the STOP mode is reached, the program initiates the change to the OFFLINE mode. Reaction: The DP master changes to the OFFLINE mode. 4 OFFLINE The DP user program queries the OFFLINE mode. 36 C79000-G8976-C139-09

37 Overview of PROFIBUS DP 2.9 Separation of the Slave Data from the DP Master User Program The process image is separate from the DP master user program and the slaves To increase efficiency, the DP standard does not include flow control. The timing of the cyclic updating of the process image of the DP master is connected neither to the DP slaves nor to the DP master user program. Examples of different situations are shown below: Example: Slave input data changes extremely quickly If, for example, an analog slave modifies its output data more quickly than it can be fetched in the polling cycle of the DP master (sample sequence 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8,...), the DP master only receives a sequence of "snapshots" that it enters in the process image (sequence 1.1, 1.3, 1.5, 1.8,...). Example: The DP master user program reads very quickly If the DP master user program reads the process image more quickly than it can be updated within the polling cycle of the DP master, values will be obtained more than once. Based on the example above, the DP master user program then, for example, reads a sequence 1.1, 1.1, 1.1, 1.1, 1.2, 1.2, 1.2, 1.2, 1.3, 1.3, 1.3, 1.3, 1.4, Example: DP master user program writes very quickly If the DP master user program writes output data to the process image faster than this can be transferred to the slave within the polling cycle of the DP master, only a series of "snapshots" will be transferred the slave (sample sequence 1, 4, 6,...) Example: DP master user program reads very slowly If the DP master user program only reads the process image occasionally, for example because it has other tasks to perform in the meantime, it is possible that some values will be skipped. A sequence such as 1.1, 1.2, 1.3, 1.4 in the process image then becomes, for example, 1.1, 1.3 etc. in the DP master user program. C79000-G8976-C

38 Overview of PROFIBUS DP Remedy If the DP master user program requires a better link to the slave than described above, there are a number of options available: With the hardware events of the CP 5613/CP 5614, the DP master user program can be informed of changes on the slave. Under certain circumstances, this results in a faster reaction of the DP master user program to a change in the input data. With user-specific implementations on the DP master and DP slave, flow controls can be achieved to link the DP master with the DP slaves and to avoid loss of data. If the polling cycle is too slow, it may be possible to increase the update rate of the process image by increasing the data transmission rate. The hardware event at the beginning of the cycle and end of the cycle of the CP 5613/CP 5614 can be used to synchronize the DP master user program with the polling cycle. These events are only supported in the constant bus cycle time mode. It is only possible to set parameters for the constant bus cycle time with STEP 7/NCM. 38 C79000-G8976-C139-09

39 Overview of PROFIBUS DP 2.10 Reliability of DP Reliability Concept The DP programming interface provides various mechanisms to limit the effects of the failure of a communication connection or the DP master. A watchdog function can be configured for the DP slave so that if a DP slave is not accessed for a longer period of time it can change automatically to a safe state. The AUTOCLEAR function can be activated to ensure that if DP slaves are not accessible, the DP master automatically changes from OPERATE to the (AUTO)CLEAR mode. A sign-of-life monitoring function can be activated on the CP 5613/CP 5614 to detect inactivity of a DP user program (failure) and to change the DP slaves to a safe operating mode. The AUTOCLEAR function The AUTOCLEAR option can be set during configuration. How it works: If an error occurs on one or more DP slaves during the productive phase, the DP master changes automatically from the OPERATE mode to the AUTOCLEAR mode (switches to a safe mode). In the AUTOCLEAR mode, the DP master behaves just as in the CLEAR mode. The DP master then sends data in the output direction with the value 0 or empty frames to the DP slaves. The DP master can no longer exit the AUTOCLEAR mode automatically; in other words, the change to the OPERATE mode must be triggered explicitly by the user. C79000-G8976-C

40 Overview of PROFIBUS DP 2.11 Control Frames to One or More Slaves Purpose of Control Frames For particular applications, there are four control commands available with which a control frame can be sent. In standard applications, these are not required. A control frame is a frame that the master sends to one slave, a group, several groups, or to all slaves. These frames are not acknowledged by the slaves. Control frames are used to transfer control commands (known as global controls) to the selected slaves to allow synchronization. A control command contains three components: Identifier indicating whether one or more DP slaves are being addressed Identification of the slave group Control command Creating Groups During configuration, you can assign a group identifier to a slave; in other words, it is possible to include several slaves in one group. Which slaves belong to a group is specified when you create the database. During this phase, each DP slave can be assigned a group number. The DP slave is informed of this group number during the parameter assignment phase. You can specify a maximum of eight groups. 40 C79000-G8976-C139-09

41 Overview of PROFIBUS DP Control Commands The following control commands can be sent to DP slaves when necessary during operation: Control Commands FREEZE UNFREEZE SYNC UNSYNC Description After receiving the FREEZE command, the DP slaves freeze the current states of all inputs. In the read cycles that follow, the DP master receives this frozen input data. The current input data is available to the DP master only after an UNFREEZE command or a further FREEZE command; with the additional FREEZE command this only applies to the current cycle. After receiving the UNFREEZE command, the freezing of the inputs is canceled. The DP slaves once again provide the DP master with the current input data. When the DP slaves receive the SYNC command, they freeze the current states of all outputs. The output data sent by the DP master following this is initially not accepted by the DP slaves. The current output data is accepted by the DP slaves only following an UNSYNC command or a further SYNC command; with the additional SYNC command, this applies only to the current cycle. After receiving the UNSYNC command, the freezing of the outputs is canceled. The current output data is accepted by the DP slaves again cyclically. C79000-G8976-C

42 Overview of PROFIBUS DP 2.12 The Importance of Configuration Using the DP Database The DP database contains information about the bus parameters of PROFIBUS and about the slaves on the network. This information is evaluated when the CP 5613/CP 5614 starts up. Configuring Slave Data Areas During configuration, you specify the number and type (input, output, analog, digital) of the data areas of all the slaves. This configuration data is sent to the slave during startup and is then checked by the slave. If the configuration data does not match the actual properties of the slave, the slave enters this in the diagnostic data and it is not included in cyclic operation. Activating the Watchdog If the watchdog of a DP slave is activated in the configuration, the DP master must communicate with the DP slave within a selected time. If there is no communication within this time, the DP slave switches its outputs to a safe state and no longer takes part in data transfer with the DP master section since the DP slave assumes that a serious problem has occurred, for example wire break or failure of the DP master. The DP master must then assign parameter values to the DP slave and configure it again. Following this, the exchange of productive data can be resumed. The values adopted by the outputs can be found in the descriptions of the DP slaves. Configuring the AUTOCLEAR Property If one of the activated slaves does not take part in the data transfer and if the AUTOCLEAR function is set, the DP master automatically changes to the CLEAR mode (with the coding AUTOCLEAR). 42 C79000-G8976-C139-09

43 Overview of PROFIBUS DP Configuring Direct Data Exchange The CP 5613/CP 5614 supports direct data exchange during cyclic polling. Only specially designed DP slaves (publishers/subscribers) are capable of direct data exchange. In direct data exchange, the publisher (transmitting slave) sends the response data with a special identifier and special timing so that not only the DP master but also the other DP slaves (subscribers) can listen in. You configure direct data exchange with STEP 7/NCM. Configuring the "Min_Slave_Interval" The "Min_Slave_Interval" is the minimum time between the DP master addressing a DP slave in two consecutive polling cycles. This is calculated automatically based on the GSD data of the slaves. Meaning of GSD Files Project engineering tools for the PROFIBUS DP master interpret the GSD files of the various DP slave types and generate the database of the DP master based on this information. To be able to use the slave module of the CP 5614, a suitable GSD file must be available. For more detailed information on this topic, refer to Section C79000-G8976-C

44 Overview of PROFIBUS DP 2.13 DP-V1 as an Extension of DP Overview of the DP Protocol with DP-V1 Extensions Apart from cyclic DP master operation (see Section 2.3.1), two further extensions are defined as DP-V1: DPC1 and DPC2. The paragraphs below contain an overview of these extensions: PG/PC DP master class 1 PG/PC DP master class 2 User program DP/DPC1 progr. interface User program DPC2 progr. interface DPC1 DP DPC2 Acyclic mode MSAC_C1 Cyclic mode MSCY_C1 Acyclic mode MSAC_C2 DP slave with DP-V1 additional functions DP-V1 Master Class 1 (DPC1) With DPC1, a cyclic DP master can also send or read slave data records and receive and acknowledge alarms. This data is not process data but slave-specific additional data (for example, data records for reassignment of parameter values). 44 C79000-G8976-C139-09

45 Overview of PROFIBUS DP DP-V1 Master Class 2 (DPC2) An additional DP master that is not operating cyclically can establish connections to DP-V1 slaves using DPC2 initiate calls and send or read data records to or from the slaves, for example for reassigning parameter values or diagnostics. C79000-G8976-C

46 Overview of PROFIBUS DP 46 C79000-G8976-C139-09

47 Overview of the DP Base Interface 3 The programming interface of the CP 5613/CP 5614 is known as the DP Base programming interface. This chapter explains the basic characteristics of the DP Base programming interface including typical call and access sequences to prepare you for creating your own DP applications. For a detailed description of the function calls and data access, please refer to Chapter 4. C79000-G8976-C

48 Overview of the DP Base Interface 3.1 Ways of Accessing the CP 5613/CP 5614 Communications Processor Overview There are basically two mechanisms with which you can access the CP 5613/CP 5614 communications processor: Function calls (DP Base programming interface) Access to the dual-port RAM of the CP 5613/CP 5614 (process image) using pointers The DP user program uses the functions of the supplied DLLs. These are passed on to the CP 5613/CP 5614 communications processors by the drivers. The DP user program can also access the process image on the communications processor with a C pointer. DP user program dp_base.dll dps_base.dll C pointer Drivers Process image CP 5613/CP C79000-G8976-C139-09

49 Overview of the DP Base Interface Access Using Pointers While your DP user program is running, data of the CP 5613 and CP 5614 that is required regularly is available directly in the dual-port RAM. Most importantly, this data includes the process image (input, output, and diagnostic data of the DP slaves) along with a variety of status and configuration data and control registers. The "DP_get_pointer" function call provides the base address (C pointer) for the DPR_CP5613_DP_T structure. With this C pointer, your DP user program can access the process image and the other data areas in the dual-port RAM efficiently. The DPR_CP5613_DP_T structure describes the structure of the data above in the dual-port RAM of the CP 5613 and CP C79000-G8976-C

50 Overview of the DP Base Interface Function Calls Your user program can execute administrative tasks and make use of less commonly required communication properties of the CP 5613 and CP 5614 during run time by calling functions of the DP Base programming interface. The DP Base programming interface is a C programming interface and consists of two DLLs. The table below describes the two DLLs: DLL Name Description Function Name dp_base.dll Contains DP master Function names start with "DP_". functions of the CP 5613/CP dps_base.dll Contains DP slave functions of the CP Function names start with "DPS_" (the S stands for slave submodule). The DP Base programming interface also includes the following header files and import libraries: Header Files dp_5613.h (definitions for DP master) dps_5614.h (definitions for DP slave) 5613_ret.h (error codes for DP master) 5614_ret.h (error codes for DP DP slave) Import Libraries dp_base.lib (master functions) dps_base.lib (slave functions) 50 C79000-G8976-C139-09