Rockwell Automation 1764-xxxx MICROLOGIX 1500 PROGRAMMABLE CONTROLLERS User Manual
Page 9

Publication 1764-UM001B-EN-P - April 2002
Table of Contents ix
Upgrading Your Operating System
Preparing for Upgrade. . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1
Performing the Upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . D-2
Missing/Corrupt OS LED Pattern . . . . . . . . . . . . . . . . . . . . D-2
Understanding Communication
Protocols
RS-232 Communication Interface . . . . . . . . . . . . . . . . . . . . E-1
DF1 Full-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . E-1
DF1 Half-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . E-2
DF1 Half-Duplex Operation . . . . . . . . . . . . . . . . . . . . . E-2
Considerations When Communicating as a DF1 Slave
on a Multi-drop Link . . . . . . . . . . . . . . . . . . . . . . . . . . E-3
Dial-Up Phone Modems . . . . . . . . . . . . . . . . . . . . . . . . E-4
Leased-Line Modems . . . . . . . . . . . . . . . . . . . . . . . . . . E-4
Radio Modems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-5
Line Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-5
DH-485 Communication Protocol. . . . . . . . . . . . . . . . . . . . E-5
DH-485 Network Description . . . . . . . . . . . . . . . . . . . . E-5
DH-485 Token Rotation . . . . . . . . . . . . . . . . . . . . . . . . E-6
DH-485 Configuration Parameters. . . . . . . . . . . . . . . . . E-6
Devices that Use the DH-485 Network . . . . . . . . . . . . . E-7
Important DH-485 Network Planning Considerations . . . E-8
System Loading and Heat
Dissipation
Selecting System Devices . . . . . . . . . . . . . . . . . . . . . . . F-2
Verifying the System Loading . . . . . . . . . . . . . . . . . . . . F-4
Calculating Heat Dissipation . . . . . . . . . . . . . . . . . . . . . . . F-9