This chapter describes the basic characteristics of the distributed input/output system: • Central control by a master • High data throughput with a simple transmission protocol • Cyclic transmission of the process image in the input/output direction • Simple, cost-effective attachment • Data transmission via twisted pair (RS 485) or optical fiber | SIEMENS SIMATIC NET DP Programming Interface Cyclic Communication Manual C79000-B8976-C071-07 1 Distributed I Os 2 Characteristics of the DP Programming Interface 3 Basic Principles of Distributed I Os DP 4 Structure of the DP Programming Interface 5 Description of the DP Functions 6 Data Storage 7 Creating DOS Applications 8 Creating Windows Applications 9 Creating Unix Applications Index Glossary Note We would point out that the contents of this product documentation shall not become a part of or modify any prior or existing agreement commitment or legal relationship. The Purchase Agreement contains the complete and exclusive obligations of Siemens. Any statements contained in this documentation do not create new warranties or restrict the existing warranty. We would further point out that for reasons of clarity these operating instructions cannot deal with every possible problem arising from the use of this device. Should you require further information or if any special problems arise which are not sufficiently dealt with in the operating instructions please contact your local Siemens representative. General This device is electrically operated. In operation certain parts of this device carry a dangerously high voltage. WARNING Failure to heed warnings may result in serious physical injury and or material damage. Only appropriately qualified personnel may operate this equipment or work in its vicinity. Personnel must be thoroughly familiar with all warnings and maintenance measures in accordance with these operating instructions. Correct and safe operation of this equipment requires proper transport storage and assembly as well as careful operator control and maintenance. Personnel qualification requirements Qualified personnel as referred to in the operating instructions or in the warning notes are defined as persons who are familiar with the installation assembly startup and operation of this product and who possess the relevant qualifications for their work
