Download Controller Examples for EtherNet/IP Network
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Using Explicit Messaging Chapter 3 SLC 500 Controller – Formatting a Message to Write Multiple Parameters Figure 43 - Custom Scattered Write Multiple Message Configuration Dialog Boxes The following table identifies the data that is required in each box to configure a message to write multiple parameters. General Tab Size in Words Receive Data Send Data Data Table Address Receive Data Send Data Service (1) Service Code Class Instance Attribute Example Value Description N90:0 N100:0 Custom 4E (Hex.) (3) 93 or 9F (Hex.) (4) 0 (Dec.) 0 (Dec.) Each word size is a 16-bit integer. Number of words to be received. Number of words to be sent. An unused controller data table address containing the message instruction. This address is the starting word of the response file. This address is the starting word of the request file. Required for scattered messages. Code for the requested service. Class ID for the DPI Parameter Object. Required for scattered messages. Required for scattered messages. MultiHop Tab Example Value Description To Address 10.91.100.79 IP address of the option module connected to the drive. 20 (2) 20 (2) (1) The default setting for Service is ‘Custom’, enabling entry of a Service Code not available from the Service pull-down menu. When choosing a Service other than ‘Custom’ from the pull-down menu, an appropriate Hex. value is automatically assigned to the Service Code box that is dimmed (unavailable). (2) In this example, we are writing to five 32-bit REAL (floating point) parameters. Each parameter being written to requires four contiguous 16-bit words. Scattered write messages always assume that every parameter being written to is a 32-bit parameter, regardless of its actual size. The data structure format is shown on page 70. Maximum length is 128 words, which equates to 32 parameters. For parameter numbering, see DPI Parameter Object on page 94 (Class code 0x93) or Host DPI Parameter Object on page 108 (Class code 0x9F). (3) Service Code 4E write messages are written to the drive’s Nonvolatile Storage (EEPROM) memory, so the parameter value will remain even after the drive is power cycled. Important: Be very cautious as the EEPROM may quickly exceed its life cycle and cause the drive to malfunction. (4) See Table 6 on page 50 for limitations of PowerFlex 750-Series drives when using DPI Parameter Object Class code 0x93 or Host DPI Parameter Object Class code 0x9F for explicit messaging. Rockwell Automation Publication 750COM-AT001A-EN-P - August 2012 67