Rockwell Automation 2755 Enhanced Decoder Series B - Manual (Page 33)

3–3 Overview of Decoder Operations
Publication 2755-833
The decoder can also communicate directly with a host computer or
PLC in a control or data collection application. The decoder
communicates with and transmits bar code data to a host computer or
PLC controller via the HOST port of the decoder.
Programmable Logic Controllers (PLC)
The decoder connects to an Allen-Bradley PLC Controller in the
following ways (see Figure 3.1):
1. Flexible Interface Module (Catalog No. 2760-RB) which
supports a:
– point-to-Point link using the RS-232, RS-422, or DH485
interface to the HOST port
– multi-drop link using the DH485 interface of the HOST port
and the Flexible Interface Module.
Each port of the Module operates as a separate network,
supporting up to 31 decoders
Use the Catalog No. 2760-SFC2 protocol cartridge with the
Flexible Interface Module and configure the decoder for
DH485 mode.
2. Catalog No. 1771-DB BASIC Module or 1771-DA ASCII I/O
Module connects decoder directly to a PLC.
3. Programmable logic controllers from the Allen-Bradley PLC-5
t
family of products that support an RS-232 ASCII port.
Host Operation