Application Layer Application Layer This section describes the meaning of data read from and written to the Siemens Milltronics SmartLinx instrument slave memory. The output words (PLC master Write operation) and input words (PLC master Read operation) are described in the Data Map for Level Products on page 24 and the Data Map for Mass Dynamic Products on page 30. Parameter Indexes Most parameters used on Siemens Milltronics SmartLinx instruments are indexed. Indexing allows a parameter to relate to more than one input or output. For example, many parameters are indexed by measurement point while others are indexed by relay output or discrete input.
The way that indexes are handled in the memory map depends on the data access method used. Primary Index An index that relates to an input or output is called a Primary Index. (On some older Siemens Milltronics products the primary index is called a point.) Example: P111[3] = 52 means P111 (Relay Control Function) for relay 3 is set to value 52. 52 7ML19981AQ03 SmartLinx PROFIBUS DP – INSTRUCTION MANUAL Page 19 P111 [1] [2] [3] [4] [5]