Module: df1

DF1 is only available on devices that have been licensed to use DF1. DF1 is the object returned when the plugin is loaded. It is the starting point for creating connections to DF1 servers.

This plugin is the client half of a client/server pair. This means that it can initiate a connection to a DF1 server and then issue commands to read/write portions of the server memory map. Since the server only responds to requests from the client, the client must occasionally re-read the parts of the memory map that it is interested in keeping current.

To connect to a DF1 server, a memory map for the server is required. A memory map is XML that describes how the memory is organized. When applied, the attributes described in the map become accessible to JavaScript. JavaScript can then write to the outputs and connect to changed events on the inputs. See Memory Map for more detail. Setting up a DF1 memory map is very similar to FLNet, except that there are no fixed input/output areas. Instead, each 'object' that is to be read or written is placed into a 'pccc' section in the 'map' section. For example:

<map>
 <pccc>
  <Object1Type name="Object1Name" addr="N7:90"/>
  <Object2Type name="Object2Name" addr="N7:100"/>
 </pccc>
</map>

The 'addr' attribute specifies the address in the server of the start of the object. The length of the object is derived from the type definition of the object. See FLNet Memory Map for an example of how to set up an FLNet memory map.

The name of the plugin for loading 'df1'.

About

DF-1 / DF1 protocol is an asynchronous byte-oriented protocol that is used to communicate with most Allen Bradley RS232 interface modules. DF1 protocol consists of link layer and application layer formats. Link layer serial frame is a composition of conventional RS-232 serial frame with the parameters specified as 8 data bits, no parity, and a maximum baud rate of 19200. DF1 is ASCII character oriented protocol and works over half duplex and full duplex modes of communication.

See:

Requires