ProSoft MVI56E-FLN, Руководство пользователя

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Reference MVI56E-FLN ♦ ControlLogix Platform
User Manual FA Control Network Ethernet Communication Module
Page 94 of 155 ProSoft Technology, Inc.
Common Memory

The Common Memory interface provides nodes with a service that can be
regarded as a memory shared among them.

Data on the Common Memory is refreshed cyclically as each node updates
and broadcasts its memory contents.

Each node broadcasts its data in a fixed cycle and all the nodes in a network
share the same data on the Common Memory.

A user can use the Common Memory as global area in the node.

The Common Memory size is 8k bits + 8k words = 8.5k words in a whole
network.
Area 1 and Area 2

The Common Memory is divided into two areas.

Area 1 has 512 words and Area 2 has 8192 words (1 word = 2 bytes = 16
bits)

The maximum quantity of data that can be transmitted by a single node is
8.5k words.