Rockwell Automation 1762-Lxxxx MicroLogix 1200 Programmable Controllers - Manual (Page 133)

Publication 1762-UM001G-EN-P - March 2011
Connect to Networks via RS-232 Interface E-3
Example DF1 Half-duplex Connections
Use Modems with MicroLogix 1200 Programmable Controllers
The types of modems you can use with MicroLogix 1200 controllers include
the following:
• dial-up phone modems
A MicroLogix 1200 controller, on the receiving end of the dial-up
connection, can be configured for DF1 Full-duplex protocol with or
without handshaking. The modem connected to the MicroLogix
controller should support auto-answer. The MicroLogix 1200 supports
ASCII out communications. Therefore, it can cause a modem to initiate
or disconnect a phone call.
• leased-line modems
Leased-line modems are used with dedicated phone lines that are
typically leased from the local phone company. The dedicated lines may
be in a point-to-point topology supporting Full-duplex communications
between two modems or in a multi-drop topology supporting
Half-duplex communications between three or more modems.
TERM A B COM SHLD CHS GND
TX
TX PWR
TX
DC SOURCE CABLE
EXTERNAL
TERM A B COM SHLD CHS GND
TX
TX PWR
TX
DC SOURCE CABLE
EXTERNAL
TERM A B COM SHLD CHS GND
TX
TX PWR
TX
DC SOURCE CABLE
EXTERNAL
Rockwell Software RSLinx 2.0 (or
higher), SLC 5/03, SLC 5/04, and
SLC 5/05, or PLC-5 processors
configured for DF1 Half-duplex
Master. RS-232
(DF1 Half-duplex Protocol)
MicroLogix
1500 (Slave) SLC 5/04 (Slave) MicroLogix
1000 (Slave) SLC 5/03 with
1747-KE Interface
Module (Slave) MicroLogix
1200 (Slave)
Modem