Rockwell Automation 1785 PLC-5 Specifications download pdf (Page 28)

28 PLC-5 Ethernet Interface Module

Publication 1785-IN019B-EN-P - January 2007

The MSG instruction transfers data in packets. Each packet can contain up to 709 words for

Ethernet controllers and interface modules. If your message transfer contains more words

than fit in one packet, the transfer requires more than one packet of transfer data. The more

packets of data to transfer, the longer the total transfer takes.

Enter Parameters

The control block is where all of the information relating to the message is stored. Ethernet

message instructions use two consecutive control blocks:

Use your programming software package to enter the control block address. After entering

the control block, the programming terminal automatically displays a data entry dialog, from

which you enter instruction parameters that are stored at the control block address.

Parameter Descriptions

When you enter 3A as the port number, an Ethernet instruction entry dialog appears. In

addition to the information you entered previously, this dialog includes a field for entering the

Host/Internet (IP) address. Enter the IP address of the destination controller here.

This Block Contains

First Message information

Second Destination address

IMPORTANT

Because Ethernet messages need two consecutive control blocks, the

message control block that you specify must start on an even element

number.

This Parameter Specifies

Command Type Whether the MSG instruction performs a read or write operation. The software toggles

between: PLC-5 Typed Read, PLC-5 Typed Write, PLC-5 Typed Write to SLC, PLC-5 Typed

Read from SLC, SLC Typed Logical Read, SLC Typed Logical Write, PLC-2 Unprotected

Read, PLC-2 Unprotected Write, PLC-3 Word Range Read, and PLC-3 Word Range Write.

PLC-5 Data Table

Address

The data file address of the controller containing the message instruction. If the MSG

operation is write, this address is the starting word of the source file. If the MSG

operation is read, this address is the starting word of the destination file.

Size in Elements The number of elements (1...1000) to be transferred.

Destination Address The starting address of the source or destination file in the target controller.

Port Number The channel for message communications. Communications through the Ethernet

interface module use channel 3A.

1 2 ... 23 24 25 26 27 28 29 30 31 32 33 ... 47 48

No comments

Rockwell Automation 1785 PLC-5 Specifications Page 28