[December 12, 2000] [Provisional. A proposed markup language; no further details known as of 2000-12-12.]
"Batch Data Exchange Using XML." By David Emerson (Senior System Architect, Yokogawa Corporation of America). From Plantautomation.com. December, 2000. "The ISA SP88 committee has been working to develop methods for the exchange of batch data such as master recipes, batch schedules and batch histories. To date the S88.02 drafts, for the lack of a better, widely accepted format, have focused on using relational database technology for the transfer of batch data. The wide acceptance of the eXtensible Markup Language (XML) since its release by the World Wide Web Consortium (W3C) in 1998 now provides an ideal candidate format that did not exist when the SP88 committee developed the S88.02 exchange table format. This paper examines the use of XML for the exchange of batch related data. Examples are provided to demonstrate XML's ability to handle loosely coupled systems and complex, hierarchical data... When work started on the S88.02 standard in 1995 the SP88 committee evaluated alternative formats and selected relational tables as the format for exchanging batch related. Since 1995 a great deal has changed in the world of information technology, especially the emergence of Internet technologies. One of the most talked about new Internet technologies is the eXtensible Markup Language (XML). While still in its infancy, XML is experiencing rapid and wide acceptance, at least as evidenced by press releases and a trickle of products that utilize XML. As XML enters the mainstream of software tools it should be examined for use in the process control industry. Where XML is strong at handling complex, hierarchical data its application in the batch control industry appears to be especially appropriate. At this time the S88.02 standard and its international equivalent IEC 61512-2 are in their final drafts and products based on them have not become widely released. So there is a window of opportunity to utilize a new technology like XML to implement batch data exchange building upon the work of S88.02, but without the complexity and difficulties of using storage based technology for exchanging data... The on-going work of the SP88 committee as documented in S88.02 Batch Control, Part 2: Data Structures and Guidelines for Languages, draft 14, dated May 1999 defines a method for exchanging batch control information between computer programs or systems. The method involves the use of relational tables or exchange tables. The S88.02 draft standard does not propose to define the internals of batch control, or other related systems. It states that only an interface specification is being defined, not the internal requirements for a system using the interface. The S88.02 exchange tables support four types of batch data: (1) Master and control recipe information; (2) Process cell equipment information; (3) Schedule information; (4) Production information. This list represents the most important and frequently handled data for batch control. However, no list can ever be 100% complete, especially over time as new needs develop. So the S88.02 draft also states that the exchange table definitions may be extended to support additional data. The additional data could be vendor specific data such as data addresses, end-user data that may support corporate business rules, or even some industry specific data such as may be useful for the pharmaceutical or other industry. The ability to extend the exchange tables is an acknowledgement that no one format can be all encompassing and fluid enough to handle all, or perhaps even most, applications over time. By permitting the expansion of the exchange tables the SP88 committee has enabled them to grow and be adapted as needed... A set of XML schemas based on the S88.02 data model and exchange tables could be created for using XML to exchange batch control related data. A logical set of schemas would be: (1) master and control recipes, (2) batch schedules, (3) equipment definitions, and (4) production information. This grouping would match the data models and exchange table organization. Collectively this group of schemas could be called a Batch Control Markup Language (BatchML or BCML for short) and used as the basis for exchanging batch control related data in a variety of environments and applications. The work being done by the ISA SP88 committee provides a solid basis for the development of different interfaces for the exchange of batch control data. The emergence and wide acceptance of XML in the information technology industry represents a valuable and well suited technology that can be used with the work of the SP88 committee. As the OPC Foundation has done in the development of their batch custom specification, a new group could also use XML to create a Batch Markup Language. A Batch Markup Language coupled with new and existing tools and technology could be used to lower the cost of integration of batch control related, operational and business applications in the batch processing industry."